Author name code: kuijpers
ADS astronomy entries on 2022-09-14
author:"Kuijpers, Jan M.E." 
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Title: LOPES 3D -- studies on the benefits of EAS-radio measurements
    with vertically aligned antennas
Authors: Huber, D.; Apel, W. D.; Arteaga-Velazquez, J. C.; Bähren,
   L.; Bekk, K.; Bertaina, M.; Biermann, P. L.; Blümer, J.; Bozdog,
   H.; Brancus, I. M.; Cantoni, E.; Chiavassa, A.; Daumiller, K.; de
   Souza, V.; Di Pierro, F.; Doll, P.; Engel, R.; Falcke, H.; Fuchs,
   B.; Fuhrmann, D.; Gemmeke, H.; Grupen, C.; Haungs, A.; Heck, D.;
   Hörandel, J. R.; Horneffer, A.; Huege, T.; Isar, P. G.; Kampert,
   K. -H.; Kang, D.; Krömer, O.; Kuijpers, J.; Link, K.; Łuczak, P.;
   Ludwig, M.; Mathes, H. J.; Melissas, M.; Morello, C.; Oehlschläger,
   J.; Palmieri, N.; Pierog, T.; Rautenberg, J.; Rebel, H.; Roth,
   M.; Rühle, C.; Saftoiu, A.; Schieler, H.; Schmidt, A.; Schoo, S.;
   Schröder, F. G.; Sima, O.; Toma, G.; Trinchero, G. C.; Weindl, A.;
   Wochele, J.; Zabierowski, J.; Zensus, J. A.
Bibcode: 2022arXiv220814664H
Altcode:
  The LOPES experiment was a radio interferometer built at the existing
  air shower array KASCADE-Grande in Karlsruhe, Germany. The last
  configuration of LOPES was called LOPES 3D and consisted of ten tripole
  antennas. Each of these antennas consisted of three crossed dipoles
  east-west, north-south, and vertically aligned. With this, LOPES 3D
  had the unique possibility to study the benefits of measurements
  with vertically aligned antennas in the environment of the well
  understood and calibrated particle detector array KASCADE-Grande. The
  measurements with three spatially coincident antennas allows a redundant
  reconstruction of the electric field vector. Several methods to exploit
  the redundancy were developed and tested. Furthermore, for the first
  time in LOPES, the background noise could be studied polarization-
  and direction dependent. With LOPES 3D it could be demonstrated that
  radio detection reaches a higher efficiency for inclined showers when
  including measurements with vertically aligned antennas and that the
  vertical component gets more important for the measurement of inclined
  showers. In this contribution we discuss a weighting scheme for the
  best combination of three redundant reconstructed electric field
  vectors. Furthermore, we discuss the influence of these weighting
  schemes on the ability to reconstruct air showers using the radio
  method. We show an estimate of the radio efficiency for inclined
  showers with focus on the benefits of measurements with vertically
  aligned antennas and we present the direction dependent noise in the
  different polarizations.

Title: Final results of the LOPES radio interferometer for cosmic-ray
    air showers
Authors: Apel, W. D.; Arteaga-Velázquez, J. C.; Bähren, L.; Bekk, K.;
   Bertaina, M.; Biermann, P. L.; Blümer, J.; Bozdog, H.; Cantoni, E.;
   Chiavassa, A.; Daumiller, K.; de Souza, V.; di Pierro, F.; Doll, P.;
   Engel, R.; Falcke, H.; Fuchs, B.; Gemmeke, H.; Grupen, C.; Haungs,
   A.; Heck, D.; Hörandel, J. R.; Horneffer, A.; Huber, D.; Huege,
   T.; Isar, P. G.; Kampert, K. -H.; Kang, D.; Krömer, O.; Kuijpers,
   J.; Link, K.; Łuczak, P.; Ludwig, M.; Mathes, H. J.; Melissas, M.;
   Morello, C.; Nehls, S.; Oehlschläger, J.; Palmieri, N.; Pierog,
   T.; Rautenberg, J.; Rebel, H.; Roth, M.; Rühle, C.; Saftoiu, A.;
   Schieler, H.; Schmidt, A.; Schoo, S.; Schröder, F. G.; Sima, O.;
   Toma, G.; Trinchero, G. C.; Weindl, A.; Wochele, J.; Zabierowski,
   J.; Zensus, J. A.; Lopes Collaboration
Bibcode: 2021EPJC...81..176A
Altcode: 2021arXiv210203928A
  LOPES, the LOFAR prototype station, was an antenna array for cosmic-ray
  air showers operating from 2003 to 2013 within the KASCADE-Grande
  experiment. Meanwhile, the analysis is finished and the data of
  air-shower events measured by LOPES are available with open access in
  the KASCADE Cosmic Ray Data Center (KCDC). This article intends to
  provide a summary of the achievements, results, and lessons learned
  from LOPES. By digital, interferometric beamforming the detection of air
  showers became possible in the radio-loud environment of the Karlsruhe
  Institute of Technology (KIT). As a prototype experiment, LOPES tested
  several antenna types, array configurations and calibration techniques,
  and pioneered analysis methods for the reconstruction of the most
  important shower parameters, i.e., the arrival direction, the energy,
  and mass-dependent observables such as the position of the shower
  maximum. In addition to a review and update of previously published
  results, we also present new results based on end-to-end simulations
  including all known instrumental properties. For this, we applied the
  detector response to radio signals simulated with the CoREAS extension
  of CORSIKA, and analyzed them in the same way as measured data. Thus,
  we were able to study the detector performance more accurately than
  before, including some previously inaccessible features such as the
  impact of noise on the interferometric cross-correlation beam. These
  results led to several improvements, which are documented in this
  paper and can provide useful input for the design of future cosmic-ray
  experiments based on the digital radio-detection technique.

Title: Interferometric Radio Measurements of Air Showers with LOPES:
    Final Results
Authors: Schröder, F. G.; Link, K.; Apel, W. D.; Arteaga-Velázquez,
   J. C.; Bähren, L.; Bekk, K.; Bertaina, M.; Biermann, P. L.;
   Blümer, J.; Bozdog, H.; Brancus, I. M.; Cantoni, E.; Chiavassa,
   A.; Daumiller, K.; de Souza, V.; Di Pierro, F.; Doll, P.; Engel, R.;
   Falcke, H.; Fuchs, B.; Gemmeke, H.; Grupen, C.; Haungs, A.; Heck, D.;
   Hörandel, J. R.; Horneffer, A.; Huber, D.; Huege, T.; Isar, P. G.;
   Kampert, K. H.; Kang, D.; Krömer, O.; Kuijpers, J.; Łuczak, P.;
   Ludwig, M.; Mathes, H. J.; Melissas, M.; Morello, C.; Oehlschläger,
   J.; Palmieri, N.; Pierog, T.; Rautenberg, J.; Rebel, H.; Roth, M.;
   Rühle, C.; Saftoiu, A.; Schieler, H.; Schmidt, A.; Schoo, S.; Sima,
   O.; Toma, G.; Trinchero, G. C.; Weindl, A.; Wochele, J.; Zabierowski,
   J.; Zensus, J. A.; Lopes Collaboration
Bibcode: 2017ICRC...35..458S
Altcode: 2017PoS...301..458S; 2017arXiv170800626S
  LOPES was the radio extension of the KASCADE-Grande particle-detector
  array consisting of up to 30 antennas measuring the radio emission of
  cosmic-ray air showers between 40 and 80 MHz with an energy threshold
  of around 100 PeV. Even with the external trigger by the particle
  detectors, the separation of the air-shower signal from the radio
  background was difficult in the noisy environment of the Karlsruhe
  Institute of Technology. For the typical event this was only possible
  because of the digital, interferometric beamforming technique pioneered
  by LOPES for cosmic-ray detection. Using this technique LOPES made
  important discoveries with respect to the radio emission of air showers
  and their relation to the shower properties, such as its energy and
  its longitudinal development. By now, practically all results have
  been confirmed by subsequent antenna arrays, but regarding digital
  interferometry the LOPES results are still unique. Lately we completed
  an end-to-end pipeline for CoREAS simulations of the radio emission
  including measured background and all known detector responses as well
  as the interferometric analysis technique. As result we present an
  update on the reconstruction of the most important shower parameters:
  arrival direction, energy, and $X_\mathrm{max}$.

Title: A comparison of the cosmic-ray energy scales of Tunka-133
    and KASCADE-Grande via their radio extensions Tunka-Rex and LOPES
Authors: Apel, W. D.; Arteaga-Velázquez, J. C.; Bähren, L.;
   Bezyazeekov, P. A.; Bekk, K.; Bertaina, M.; Biermann, P. L.;
   Blümer, J.; Bozdog, H.; Brancus, I. M.; Budnev, N. M.; Cantoni, E.;
   Chiavassa, A.; Daumiller, K.; de Souza, V.; di Pierro, F.; Doll, P.;
   Engel, R.; Falcke, H.; Fedorov, O.; Fuchs, B.; Gemmeke, H.; Gress,
   O. A.; Grupen, C.; Haungs, A.; Heck, D.; Hiller, R.; Hörandel,
   J. R.; Horneffer, A.; Huber, D.; Huege, T.; Isar, P. G.; Kampert,
   K. -H.; Kang, D.; Kazarina, Y.; Kleifges, M.; Korosteleva, E. E.;
   Kostunin, D.; Krömer, O.; Kuijpers, J.; Kuzmichev, L. A.; Link, K.;
   Lubsandorzhiev, N.; Łuczak, P.; Ludwig, M.; Mathes, H. J.; Melissas,
   M.; Mirgazov, R. R.; Monkhoev, R.; Morello, C.; Oehlschläger, J.;
   Osipova, E. A.; Pakhorukov, A.; Palmieri, N.; Pankov, L.; Pierog,
   T.; Prosin, V. V.; Rautenberg, J.; Rebel, H.; Roth, M.; Rubtsov,
   G. I.; Rühle, C.; Saftoiu, A.; Schieler, H.; Schmidt, A.; Schoo,
   S.; Schröder, F. G.; Sima, O.; Toma, G.; Trinchero, G. C.; Weindl,
   A.; Wischnewski, R.; Wochele, J.; Zabierowski, J.; Zagorodnikov, A.;
   Zensus, J. A.; Tunka-Rex Collaboration; Lopes Collaboration
Bibcode: 2016PhLB..763..179A
Altcode: 2016arXiv161008343A
  The radio technique is a promising method for detection of cosmic-ray
  air showers of energies around 100PeV and higher with an array of
  radio antennas. Since the amplitude of the radio signal can be measured
  absolutely and increases with the shower energy, radio measurements can
  be used to determine the air-shower energy on an absolute scale. We
  show that calibrated measurements of radio detectors operated in
  coincidence with host experiments measuring air showers based on
  other techniques can be used for comparing the energy scales of these
  host experiments. Using two approaches, first via direct amplitude
  measurements, and second via comparison of measurements with air shower
  simulations, we compare the energy scales of the air-shower experiments
  Tunka-133 and KASCADE-Grande, using their radio extensions, Tunka-Rex
  and LOPES, respectively. Due to the consistent amplitude calibration
  for Tunka-Rex and LOPES achieved by using the same reference source,
  this comparison reaches an accuracy of approximately 10% - limited by
  some shortcomings of LOPES, which was a prototype experiment for the
  digital radio technique for air showers. In particular we show that
  the energy scales of cosmic-ray measurements by the independently
  calibrated experiments KASCADE-Grande and Tunka-133 are consistent
  with each other on this level.

Title: Improved absolute calibration of LOPES measurements and its
    impact on the comparison with REAS 3.11 and CoREAS simulations
Authors: Apel, W. D.; Arteaga-Velázquez, J. C.; Bähren, L.; Bekk, K.;
   Bertaina, M.; Biermann, P. L.; Blümer, J.; Bozdog, H.; Brancus, I. M.;
   Cantoni, E.; Chiavassa, A.; Daumiller, K.; de Souza, V.; Di Pierro,
   F.; Doll, P.; Engel, R.; Falcke, H.; Fuchs, B.; Gemmeke, H.; Grupen,
   C.; Haungs, A.; Heck, D.; Hiller, R.; Hörandel, J. R.; Horneffer, A.;
   Huber, D.; Huege, T.; Isar, P. G.; Kampert, K. -H.; Kang, D.; Krömer,
   O.; Kuijpers, J.; Link, K.; Łuczak, P.; Ludwig, M.; Mathes, H. J.;
   Melissas, M.; Morello, C.; Nehls, S.; Oehlschläger, J.; Palmieri, N.;
   Pierog, T.; Rautenberg, J.; Rebel, H.; Roth, M.; Rühle, C.; Saftoiu,
   A.; Schieler, H.; Schmidt, A.; Schoo, S.; Schröder, F. G.; Sima,
   O.; Toma, G.; Trinchero, G. C.; Weindl, A.; Wochele, J.; Zabierowski,
   J.; Zensus, J. A.
Bibcode: 2016APh....75...72A
Altcode: 2015arXiv150707389L; 2015arXiv150707389A
  LOPES was a digital antenna array detecting the radio emission of
  cosmic-ray air showers. The calibration of the absolute amplitude scale
  of the measurements was done using an external, commercial reference
  source, which emits a frequency comb with defined amplitudes. Recently,
  we obtained improved reference values by the manufacturer of the
  reference source, which significantly changed the absolute calibration
  of LOPES. We reanalyzed previously published LOPES measurements,
  studying the impact of the changed calibration. The main effect is an
  overall decrease of the LOPES amplitude scale by a factor of 2.6 ±
  0.2, affecting all previously published values for measurements of
  the electric-field strength. This results in a major change in the
  conclusion of the paper 'Comparing LOPES measurements of air-shower
  radio emission with REAS 3.11 and CoREAS simulations' published by Apel
  et al. (2013) : With the revised calibration, LOPES measurements now
  are compatible with CoREAS simulations, but in tension with REAS 3.11
  simulations. Since CoREAS is the latest version of the simulation code
  incorporating the current state of knowledge on the radio emission
  of air showers, this new result indicates that the absolute amplitude
  prediction of current simulations now is in agreement with experimental
  data.

Title: Electric Current Circuits in Astrophysics
Authors: Kuijpers, Jan; Frey, Harald U.; Fletcher, Lyndsay
Bibcode: 2016mssf.book....3K
Altcode:
  No abstract at ADS

Title: Investigation of the radio wavefront of air showers with
    LOPES measurements and CoREAS simulations (ARENA 2014)
Authors: Schröder, F. G.; Apel, W. D.; Arteaga-Velazquez, J. C.;
   Bähren, L.; Bekk, K.; Bertaina, M.; Biermann, P. L.; Blümer, J.;
   Bozdog, H.; Brancus, I. M.; Cantoni, E.; Chiavassa, A.; Daumiller,
   K.; de Souza, V.; Di Pierro, F.; Doll, P.; Engel, R.; Falcke, H.;
   Fuchs, B.; Fuhrmann, D.; Gemmeke, H.; Grupen, C.; Haungs, A.; Heck,
   D.; Hörandel, J. R.; Horneffer, A.; Huber, D.; Huege, T.; Isar,
   P. G.; Kampert, K. -H.; Kang, D.; Krömer, O.; Kuijpers, J.; Link,
   K.; Luczak, P.; Ludwig, M.; Mathes, H. J.; Melissas, M.; Morello, C.;
   Oehlschläger, J.; Palmieri, N.; Pierog, T.; Rautenberg, J.; Rebel,
   H.; Roth, M.; Rühle, C.; Saftoiu, A.; Schieler, H.; Schmidt, A.;
   Schoo, S.; Sima, O.; Toma, G.; Trinchero, G. C.; Weindl, A.; Wochele,
   J.; Zabierowski, J.; Zensus, J. A.
Bibcode: 2015arXiv150707753S
Altcode:
  We investigated the radio wavefront of cosmic-ray air showers with
  LOPES measurements and CoREAS simulations: the wavefront is of
  approximately hyperbolic shape and its steepness is sensitive to
  the shower maximum. For this study we used 316 events with an energy
  above 0.1 EeV and zenith angles below $45^\circ$ measured by the LOPES
  experiment. LOPES was a digital radio interferometer consisting of up to
  30 antennas on an area of approximately 200 m x 200 m at an altitude of
  110 m above sea level. Triggered by KASCADE-Grande, LOPES measured the
  radio emission between 43 and 74 MHz, and our analysis might strictly
  hold only for such conditions. Moreover, we used CoREAS simulations made
  for each event, which show much clearer results than the measurements
  suffering from high background. A detailed description of our result
  is available in our recent paper published in JCAP09(2014)025. The
  present proceeding contains a summary and focuses on some additional
  aspects, e.g., the asymmetry of the wavefront: According to the CoREAS
  simulations the wavefront is slightly asymmetric, but on a much weaker
  level than the lateral distribution of the radio amplitude.

Title: Electric Current Circuits in Astrophysics
Authors: Kuijpers, Jan; Frey, Harald U.; Fletcher, Lyndsay
Bibcode: 2015SSRv..188....3K
Altcode: 2014arXiv1403.0795K; 2014SSRv..tmp...19K
  Cosmic magnetic structures have in common that they are anchored in a
  dynamo, that an external driver converts kinetic energy into internal
  magnetic energy, that this magnetic energy is transported as Poynting
  flux across the magnetically dominated structure, and that the magnetic
  energy is released in the form of particle acceleration, heating, bulk
  motion, MHD waves, and radiation. The investigation of the electric
  current system is particularly illuminating as to the course of events
  and the physics involved. We demonstrate this for the radio pulsar wind,
  the solar flare, and terrestrial magnetic storms.

Title: Reconstruction of the energy and depth of maximum of cosmic-ray
    air showers from LOPES radio measurements
Authors: Apel, W. D.; Arteaga-Velazquez, J. C.; Bähren, L.; Bekk,
   K.; Bertaina, M.; Biermann, P. L.; Blümer, J.; Bozdog, H.; Brancus,
   I. M.; Cantoni, E.; Chiavassa, A.; Daumiller, K.; de Souza, V.; di
   Pierro, F.; Doll, P.; Engel, R.; Falcke, H.; Fuchs, B.; Fuhrmann,
   D.; Gemmeke, H.; Grupen, C.; Haungs, A.; Heck, D.; Hörandel, J. R.;
   Horneffer, A.; Huber, D.; Huege, T.; Isar, P. G.; Kampert, K. -H.;
   Kang, D.; Krömer, O.; Kuijpers, J.; Link, K.; Łuczak, P.; Ludwig,
   M.; Mathes, H. J.; Melissas, M.; Morello, C.; Oehlschläger, J.;
   Palmieri, N.; Pierog, T.; Rautenberg, J.; Rebel, H.; Roth, M.; Rühle,
   C.; Saftoiu, A.; Schieler, H.; Schmidt, A.; Schröder, F. G.; Sima,
   O.; Toma, G.; Trinchero, G. C.; Weindl, A.; Wochele, J.; Zabierowski,
   J.; Zensus, J. A.; Lopes Collaboration
Bibcode: 2014PhRvD..90f2001A
Altcode: 2014arXiv1408.2346A
  LOPES is a digital radio interferometer located at Karlsruhe
  Institute of Technology (KIT), Germany, that measures radio emission
  from extensive air showers at MHz frequencies in coincidence with
  KASCADE-Grande. In this article, we explore a method (slope method)
  that leverages the slope of the measured radio lateral distribution to
  reconstruct crucial attributes of primary cosmic rays. First, we present
  an investigation of the method on the basis of pure simulations. Second,
  we directly apply the slope method to LOPES measurements. Applying
  the slope method to simulations, we obtain uncertainties on the
  reconstruction of energy and depth of shower maximum (X<SUB>max</SUB>)
  of 13% and 50 g /<SUP>cm2</SUP>, respectively. Applying it to LOPES
  measurements, we are able to reconstruct energy and Xmax of individual
  events with upper limits on the precision of 20%-25% for the primary
  energy and 95 g /cm2 for Xmax, despite strong human-made noise at the
  LOPES site.

Title: The wavefront of the radio signal emitted by cosmic ray
    air showers
Authors: Apel, W. D.; Arteaga-Velázquez, J. C.; Bähren, L.; Bekk,
   K.; Bertaina, M.; Biermann, P. L.; Blümer, J.; Bozdog, H.; Brancus,
   I. M.; Cantoni, E.; Chiavassa, A.; Daumiller, K.; de Souza, V.; Di
   Pierro, F.; Doll, P.; Engel, R.; Falcke, H.; Fuchs, B.; Gemmeke, H.;
   Grupen, C.; Haungs, A.; Heck, D.; Hörandel, J. R.; Horneffer, A.;
   Huber, D.; Huege, T.; Isar, P. G.; Kampert, K. -H.; Kang, D.; Krömer,
   O.; Kuijpers, J.; Link, K.; Łuczak, P.; Ludwig, M.; Mathes, H. J.;
   Melissas, M.; Morello, C.; Oehlschläger, J.; Palmieri, N.; Pierog,
   T.; Rautenberg, J.; Rebel, H.; Roth, M.; Rühle, C.; Saftoiu, A.;
   Schieler, H.; Schmidt, A.; Schoo, S.; Schröder, F. G.; Sima, O.;
   Toma, G.; Trinchero, G. C.; Weindl, A.; Wochele, J.; Zabierowski,
   J.; Zensus, J. A.
Bibcode: 2014JCAP...09..025A
Altcode: 2014arXiv1404.3283A
  Analyzing measurements of the LOPES antenna array together with
  corresponding CoREAS simulations for more than 300 measured events
  with energy above 10<SUP>17</SUP> eV and zenith angles smaller than
  45<SUP>̂</SUP>, we find that the radio wavefront of cosmic-ray air
  showers is of approximately hyperbolic shape. The simulations predict
  a slightly steeper wavefront towards East than towards West, but
  this asymmetry is negligible against the measurement uncertainties of
  LOPES. At axis distances ≳ 50 m, the wavefront can be approximated by
  a simple cone. According to the simulations, the cone angle is clearly
  correlated with the shower maximum. Thus, we confirm earlier predictions
  that arrival time measurements can be used to study the longitudinal
  shower development, but now using a realistic wavefront. Moreover, we
  show that the hyperbolic wavefront is compatible with our measurement,
  and we present several experimental indications that the cone angle is
  indeed sensitive to the shower development. Consequently, the wavefront
  can be used to statistically study the primary composition of ultra-high
  energy cosmic rays. At LOPES, the experimentally achieved precision
  for the shower maximum is limited by measurement uncertainties to
  approximately 140 g/c <SUP>2</SUP>. But the simulations indicate that
  under better conditions this method might yield an accuracy for the
  atmospheric depth of the shower maximum, X<SUB>max</SUB>, better than
  30 g/c <SUP>2</SUP>. This would be competitive with the established
  air-fluorescence and air-Cherenkov techniques, where the radio technique
  offers the advantage of a significantly higher duty-cycle. Finally,
  the hyperbolic wavefront can be used to reconstruct the shower geometry
  more accurately, which potentially allows a better reconstruction of
  all other shower parameters, too.

Title: Comparing LOPES measurements of air-shower radio emission
    with REAS 3.11 and CoREAS simulations
Authors: Apel, W. D.; Arteaga-Velázquez, J. C.; Bähren, L.; Bekk,
   K.; Bertaina, M.; Biermann, P. L.; Blümer, J.; Bozdog, H.; Brancus,
   I. M.; Cantoni, E.; Chiavassa, A.; Daumiller, K.; de Souza, V.; di
   Pierro, F.; Doll, P.; Engel, R.; Falcke, H.; Fuchs, B.; Fuhrmann,
   D.; Gemmeke, H.; Grupen, C.; Haungs, A.; Heck, D.; Hörandel, J. R.;
   Horneffer, A.; Huber, D.; Huege, T.; Isar, P. G.; Kampert, K. -H.;
   Kang, D.; Krömer, O.; Kuijpers, J.; Link, K.; Łuczak, P.; Ludwig,
   M.; Mathes, H. J.; Melissas, M.; Morello, C.; Oehlschläger, J.;
   Palmieri, N.; Pierog, T.; Rautenberg, J.; Rebel, H.; Roth, M.; Rühle,
   C.; Saftoiu, A.; Schieler, H.; Schmidt, A.; Schröder, F. G.; Sima,
   O.; Toma, G.; Trinchero, G. C.; Weindl, A.; Wochele, J.; Zabierowski,
   J.; Zensus, J. A.
Bibcode: 2013APh....50...76A
Altcode: 2013arXiv1309.5920A
  Cosmic ray air showers emit radio pulses at MHz frequencies, which can
  be measured with radio antenna arrays - like LOPES at the Karlsruhe
  Institute of Technology in Germany. To improve the understanding of the
  radio emission, we test theoretical descriptions with measured data. The
  observables used for these tests are the absolute amplitude of the radio
  signal, and the shape of the radio lateral distribution. We compare
  lateral distributions of more than 500 LOPES events with two recent and
  public Monte Carlo simulation codes, REAS 3.11 and CoREAS (v 1.0). The
  absolute radio amplitudes predicted by REAS 3.11 are in good agreement
  with the LOPES measurements. The amplitudes predicted by CoREAS are
  lower by a factor of two, and marginally compatible with the LOPES
  measurements within the systematic scale uncertainties. In contrast to
  any previous versions of REAS, REAS 3.11 and CoREAS now reproduce the
  shape of the measured lateral distributions correctly. This reflects a
  remarkable progress compared to the situation a few years ago, and it
  seems that the main processes for the radio emission of air showers are
  now understood: The emission is mainly due to the geomagnetic deflection
  of the electrons and positrons in the shower. Less important but not
  negligible is the Askaryan effect (net charge variation). Moreover, we
  confirm that the refractive index of the air plays an important role,
  since it changes the coherence conditions for the emission: Only the
  new simulations including the refractive index can reproduce rising
  lateral distributions which we observe in a few LOPES events. Finally,
  we show that the lateral distribution is sensitive to the energy and
  the mass of the primary cosmic ray particles.

Title: Mass sensitivity in the radio lateral distribution function
Authors: Apel, W. D.; Arteaga, J. C.; Bähren, L.; Bekk, K.; Bertaina,
   M.; Biermann, P. L.; Blümer, J.; Bozdog, H.; Brancus, I. M.; Buchholz,
   P.; Cantoni, E.; Chiavassa, A.; Daumiller, K.; de Souza, V.; Di Pierro,
   F.; Doll, P.; Engel, R.; Falcke, H.; Finger, M.; Fuchs, B.; Fuhrmann,
   D.; Gemmeke, H.; Grupen, C.; Haungs, A.; Heck, D.; Hörandel, J. R.;
   Horneffer, A.; Huber, D.; Huege, T.; Isar, P. G.; Kampert, K. H.;
   Kang, D.; Krömer, O.; Kuijpers, J.; Link, K.; Łuczak, P.; Ludwig,
   M.; Mathes, H. J.; Melissas, M.; Morello, C.; Oehlschläger, J.;
   Palmieri, N.; Pierog, T.; Rautenberg, J.; Rebel, H.; Roth, M.; Rühle,
   C.; Saftoiu, A.; Schieler, H.; Schmid, A.; Schröder, F. G.; Sima,
   O.; Toma, G.; Trinchero, G. C.; Weindl, A.; Wochele, J.; Wommer, M.;
   Zabierowski, J.; Zensus, J. A.
Bibcode: 2013arXiv1308.0046A
Altcode:
  Measuring the mass composition of ultra-high energy cosmic rays is
  one of the main tasks in the cosmic rays field. Here we are exploring
  the composition signature in the coherent electromagnetic emission
  from extensive air showers, detected in the MHz frequency range. One
  of the experiments that successfully detects radio events in the
  frequency band of 40-80 MHz is the LOPES experiment at KIT. It is a
  digital interferometric antenna array and has the important advantage
  of taking data in coincidence with the particle detector array
  KASCADE-Grande. A possible method to look at the composition signature
  in the radio data, predicted by simulations, concerns the radio lateral
  distribution function, since its slope is strongly correlated with
  Xmax. Recent comparison between REAS3 simulations and LOPES data showed
  a significantly improved agreement in the lateral distribution function
  and for this reason an analysis on a possible LOPES mass signature
  through the slope method is promising. Trying to reproduce a realistic
  case, proton and iron showers are simulated with REAS3 using the LOPES
  selection information as input parameters. The obtained radio lateral
  distribution slope is analyzed in detail. The lateral slope method to
  look at the composition signature in the radio data is shown here and
  a possible signature of mass composition in the LOPES data is discussed.

Title: Reconstructing energy and X<SUB>max</SUB> of cosmic ray air
    showers using the radio lateral distribution measured with LOPES
Authors: Palmieri, N.; Apel, W. D.; Arteaga-Velázquez, J. C.; Bähren,
   L.; Bekk, K.; Bertaina, M.; Biermann, P. L.; Blümer, J.; Bozdog, H.;
   Brancus, I. M.; Chiavassa, A.; Daumiller, K.; de Souza, V.; Di Pierro,
   F.; Doll, P.; Engel, R.; Falcke, H.; Fuchs, B.; Fuhrmann, D.; Gemmeke,
   H.; Grupen, C.; Haungs, A.; Heck, D.; Hörandel, J. R.; Horneffer, A.;
   Huber, D.; Huege, T.; Isar, P. G.; Kampert, K. -H.; Kang, D.; Krömer,
   O.; Kuijpers, J.; Link, K.; Łuczak, P.; Ludwig, M.; Mathes, H. J.;
   Melissas, M.; Morello, C.; Oehlschläger, J.; Pierog, T.; Rautenberg,
   J.; Rebel, H.; Roth, M.; Rühle, C.; Saftoiu, A.; Schieler, H.;
   Schmidt, A.; Schröder, F. G.; Sima, O.; Toma, G.; Trinchero, G. C.;
   Weindl, A.; Wochele, J.; Zabierowski, J.; Zensus, J. A.
Bibcode: 2013AIPC.1535...89P
Altcode: 2013arXiv1308.0053A
  The LOPES experiment, a digital radio interferometer located at KIT
  (Karlsruhe Institute of Technology), obtained remarkable results for
  the detection of radio emission from extensive air showers at MHz
  frequencies. Features of the radio lateral distribution function (LDF)
  measured by LOPES are explored in this work for a precise reconstruction
  of two fundamental air shower parameters: the primary energy and the
  shower X<SUB>max</SUB>. The method presented here has been developed on
  (REAS3-)simulations, and is applied to LOPES measurements. Despite the
  high human-made noise at the LOPES site, it is possible to reconstruct
  both the energy and X<SUB>max</SUB> for individual events. On the
  one hand, the energy resolution is promising and comparable to the
  one of the co-located KASCADE-Grande experiment. On the other hand,
  X<SUB>max</SUB> values are reconstructed with the LOPES measurements
  with a resolution of 90 g/cm<SUP>2</SUP>. A precision on X<SUB>max</SUB>
  better than 30 g/cm<SUP>2</SUP> is predicted and achievable in a region
  with a lower human-made noise level.

Title: Cosmic ray measurements with LOPES: Status and recent results
Authors: Schröder, F. G.; Apel, W. D.; Arteaga-Velázquez, J. C.;
   Bähren, L.; Bekk, K.; Bertaina, M.; Biermann, P. L.; Blümer, J.;
   Bozdog, H.; Brancus, I. M.; Chiavassa, A.; Daumiller, K.; de Souza, V.;
   Di Pierro, F.; Doll, P.; Engel, R.; Falcke, H.; Fuchs, B.; Fuhrmann,
   D.; Gemmeke, H.; Grupen, C.; Haungs, A.; Heck, D.; Hörandel, J. R.;
   Horneffer, A.; Huber, D.; Huege, T.; Isar, P. G.; Kampert, K. -H.;
   Kang, D.; Krömer, O.; Kuijpers, J.; Link, K.; Łuczak, P.; Ludwig, M.;
   Mathes, H. J.; Melissas, M.; Morello, C.; Oehlschläger, J.; Palmieri,
   N.; Pierog, T.; Rautenberg, J.; Rebel, H.; Roth, M.; Rühle, C.;
   Saftoiu, A.; Schieler, H.; Schmidt, A.; Sima, O.; Toma, G.; Trinchero,
   G. C.; Weindl, A.; Wochele, J.; Zabierowski, J.; Zensus, J. A.
Bibcode: 2013AIPC.1535...78S
Altcode: 2013arXiv1301.2557S
  LOPES is a digital antenna array at the Karlsruhe Institute of
  Technology, Germany, for cosmic-ray air-shower measurements. Triggered
  by the co-located KASCADE-Grande air-shower array, LOPES detects the
  radio emission of air showers via digital radio interferometry. We
  summarize the status of LOPES and recent results. In particular,
  we present an update on the reconstruction of the primary-particle
  properties based on almost 500 events above 100PeV. With LOPES, the
  arrival direction can be reconstructed with a precision of at least
  0.65°, and the energy with a precision of at least 20%, which, however,
  does not include systematic uncertainties on the absolute energy
  scale. For many particle and astrophysics questions the reconstruction
  of the atmospheric depth of the shower maximum, X<SUB>max</SUB>,
  is important, since it yields information on the type of the primary
  particle and its interaction with the atmosphere. Recently, we found
  experimental evidence that the slope of the radio lateral distribution
  is indeed sensitive to the longitudinal development of the air shower,
  but unfortunately, the X<SUB>max</SUB> precision at LOPES is limited
  by the high level of anthropogenic radio background. Nevertheless,
  the developed methods can be transferred to next generation experiments
  with lower background, which should provide an X<SUB>max</SUB> precision
  competitive to other detection technologies.

Title: LOPES 3D reconfiguration and first measurements
Authors: Huber, D.; Apel, W. D.; Arteaga, J. C.; Bähren, L.; Bekk,
   K.; Bertaina, M.; Biermann, P. L.; Blümer, J.; Bozdog, H.; Brancus,
   I. M.; Buchholz, P.; Cantoni, E.; Chiavassa, A.; Daumiller, K.; de
   Souza, V.; Di Pierro, F.; Doll, P.; Engel, R.; Falcke, H.; Finger,
   M.; Fuchs, B.; Fuhrmann, D.; Gemmeke, H.; Grupen, C.; Haungs, A.;
   Heck, D.; Hörandel, J. R.; Horneffer, A.; Huege, T.; Isar, P. G.;
   Kampert, K. -H.; Kang, D.; Krömer, O.; Kuijpers, J.; Link, K.;
   Luczak, P.; Ludwig, M.; Mathes, H. J.; Melissas, M.; Morello, C.;
   Oehlschläger, J.; Palmieri, N.; Pierog, T.; Rautenberg, J.; Rebel,
   H.; Roth, M.; Rühle, C.; Saftoiu, A.; Schieler, H.; Schmidt, A.;
   Schröder, F. G.; Sima, O.; Toma, G.; Trinchero, G. C.; Weindl, A.;
   Wochele, J.; Wommer, M.; Zabierowski, J.; Zensus, J. A.
Bibcode: 2013arXiv1303.7070H
Altcode:
  The Radio detection technique of high-energy cosmic rays is based on the
  radio signal emitted by the charged particles in an air shower due to
  their deflection in the Earth's magnetic field. The LOPES experiment at
  Karlsruhe Institute of Technology, Germany with its simple dipoles made
  major contributions to the revival of this technique. LOPES is working
  in the frequency range from 40 to 80 MHz and was reconfigured several
  times to improve and further develop the radio detection technique. In
  the current setup LOPES consists of 10 tripole antennas which measure
  the complete electric field vector of the radio emission from cosmic
  rays. LOPES is the first experiment measuring all three vectorial
  components at once and thereby gaining the full information about the
  electric field vector and not only a two-dimensional projection. Such
  a setup including also measurements of the vertical electric field
  component is expected to increase the sensitivity to inclined showers
  and help to advance the understanding of the emission mechanism. We
  present the reconfiguration and calibration procedure of LOPES 3D and
  discuss first measurements.

Title: LOPES 3D - vectorial measurements of radio emission from
    cosmic ray induced air showers
Authors: Apel, W. D.; Arteaga, J. C.; Bähren, L.; Bekk, K.;
   Bertaina, M.; Biermann, P. L.; Blümer, J.; Bozdog, H.; Brancus,
   I. M.; Chiavassa, A.; Daumiller, K.; de Souza, V.; Di Pierro, F.;
   Doll, P.; Engel, R.; Falcke, H.; Fuchs, B.; Fuhrmann, D.; Gemmeke,
   H.; Grupen, C.; Haungs, A.; Heck, D.; Hörandel, J. R.; Horneffer,
   A.; Huber, D.; Huege, T.; Isar, P. G.; Kampert, K. -H.; Kang, D.;
   Krömer, O.; Kuijpers, J.; Link, K.; Luczak, P.; Ludwig, M.; Mathes,
   H. J.; Melissas, M.; Morello, C.; Oehlschläger, J.; Palmieri, N.;
   Pierog, T.; Rautenberg, J.; Rebel, H.; Roth, M.; Rühle, C.; Saftoiu,
   A.; Schieler, H.; Schmidt, A.; Schröder, F. G.; Sima, O.; Toma, G.;
   Trinchero, G. C.; Weindl, A.; Wochele, J.; Zabierowski, J.; Zensus,
   J. A.
Bibcode: 2013arXiv1303.7080A
Altcode:
  LOPES 3D is able to measure all three components of the electric
  field vector of the radio emission from air showers. This allows
  a better comparison with emission models. The measurement of the
  vertical component increases the sensitivity to inclined showers. By
  measuring all three components of the electric field vector LOPES 3D
  demonstrates by how much the reconstruction accuracy of primary cosmic
  ray parameters increases. Thus LOPES 3D evaluates the usefulness of
  vectorial measurements for large scale applications.

Title: Radio Measurements of Air Showers with LOPES
Authors: Schröder, F. G.; Apel, W. D.; Arteaga-Velazquez, J. C.;
   Bähren, L.; Bekk, K.; Bertaina, M.; Biermann, P. L.; Blümer, J.;
   Bozdog, H.; Brancus, I. M.; Cantoni, E.; Chiavassa, A.; Daumiller,
   K.; de Souza, V.; Di Pierro, F.; Doll, P.; Engel, R.; Falcke, H.;
   Fuchs, B.; Fuhrmann, D.; Gemmeke, H.; Grupen, C.; Haungs, A.; Heck,
   D.; Hörandel, J. R.; Horneffer, A.; Huber, D.; Huege, T.; Isar,
   P. G.; Kampert, K. -H.; Kang, D.; Krömer, O.; Kuijpers, J.; Link,
   K.; Łuczak, P.; Ludwig, M.; Mathes, H. J.; Melissas, M.; Morello,
   C.; Oehlschläger, J.; Palmieri, N.; Pierog, T.; Rautenberg, J.;
   Rebel, H.; Roth, M.; Rühle, C.; Saftoiu, A.; Schieler, H.; Schmidt,
   A.; Sima, O.; Toma, G.; Trinchero, G. C.; Weindl, A.; Wochele, J.;
   Zabierowski, J.; Zensus, J. A.
Bibcode: 2013JPhCS.409a2075S
Altcode:
  LOPES is a digital antenna array for the radio measurement of cosmic-ray
  air showers at energies around 10<SUP>17</SUP> eV. It is triggered
  by the KASCADE-Grande air-shower array at the Karlsruhe Institute of
  Technology (KIT), Germany. Because of an absolute amplitude calibration
  and a sophisticated data analysis, LOPES can test models for the
  radio emission to an up-to-now unachieved level, thus improving our
  understanding of the radio emission mechanisms. Recent REAS simulations
  of the air-shower radio emission come closer to the measurements
  than any previously tested simulations. We have determined the
  radio-reconstruction precision of interesting air-shower parameters
  by comparing LOPES reconstructions to both REAS simulations and
  KASCADE-Grande measurements, and present our latest results for the
  angular resolution, the energy and the X<SUB>max</SUB> reconstruction
  based on the radio measurement of about 500 air showers. Although the
  precision of LOPES is limited by the high level of anthropogenic noise
  at KIT, it opens a promising perspective for next-generation radio
  arrays in regions with a lower ambient noise level.

Title: Experimental Proof for the Sensitivity of Air Shower Radio
    Emission to the Longitudinal Shower Development
Authors: Schroder, F. G.; Apel, W. D.; Arteaga-Velazquez, J. C.;
   Bahren, L.; Bekk, K.; Bertaina, M.; Biermann, P. L.; Blumer, J.;
   Bozdog, H.; Brancus, I. M.; Cantoni, E.; Chiavassa, A.; Daumiller,
   K.; De Souza, V.; Di Pierro, F.; Doll, P.; Engel, R.; Falcke, H.;
   Fuchs, B.; Fuhrmann, D.; Gemmeke, H.; Grupen, C.; Haungs, A.; Heck,
   D.; Horandel, J. R.; Horneffer, A.; Huber, D.; Huege, T.; Isar,
   P. G.; Kampert, K. -H.; Kang, D.; Kromer, O.; Kuijpers, J.; Link,
   K.; Luczak, P.; Ludwig, M.; Mathes, H. J.; Melissas, M.; Morello, C.;
   Oehlschlager, J.; Palmieri, N.; Pierog, T.; Rautenberg, J.; Rebel, H.;
   Roth, M.; Ruhle, C.; Saftoiu, A.; Schieler, H.; Schmidt, A.; Schoo,
   S.; Sima, O.; Toma, G.; Trinchero, G. C.; Weindl, A.; Wochele, J.;
   Zabierowski, J.; Zensus, J. A.
Bibcode: 2013ICRC...33.1685S
Altcode:
  We observe a correlation between the slope of the radio lateral
  distribution measured with LOPES and the mean pseudorapidity of
  high-energy muons. The latter is reconstructed by combining the
  measurements of the muon tracking detector and the particle detector
  array of KASCADE-Grande. Since the mean muon pseudorapidity depends
  on the longitudinal shower development, the measured correlation is
  experimental evidence that also the radio signal is sensitive to the
  shower development — as has been predicted by simulations for a
  long time. For air showers interacting earlier in the atmosphere,
  i.e. old showers, the high-energy muons on average have a large
  pseudorapidity, and the lateral distribution of the radio signal is
  relatively flat. Contrary, young showers exhibit a smaller mean muon
  pseudorapidity and a steeper radio lateral distribution. The radio
  measurements seem to primarily depend on the geometrical distance
  between the shower maximum and the radio detector, and only as a
  consequence to the atmospheric depth of the shower maximum, Xmax. The
  observed correlation is statistically significant and has been published
  in Physical Review D 85, 071101(R).

Title: Vectorial Radio Interferometry with LOPES 3D
Authors: Huber, D.; Apel, W. D.; Arteaga-Velázquez, J. C.; Bähren,
   L.; Bekk, K.; Bertaina, M.; Biermann, P. L.; Blümer, J.; Bozdog,
   H.; Brancus, I. M.; Cantoni, E.; Chiavassa, A.; Daumiller, K.; de
   Souza, V.; di Pierro, F.; Doll, P.; Engel, R.; Falcke, H.; Fuchs,
   B.; Fuhrmann, D.; Gemmeke, H.; Grupen, C.; Haungs, A.; Heck, D.;
   Hörandel, J. R.; Horneffer, A.; Huege, T.; Isar, P. G.; Kampert,
   K. -H.; Kang, D.; Krömer, O.; Kuijpers, J.; Link, K.; Łuczak, P.;
   Ludwig, M.; Mathes, H. J.; Melissas, M.; Morello, C.; Oehlschläger,
   J.; Palmieri, N.; Pierog, T.; Rautenberg, J.; Rebel, H.; Roth,
   M.; Rühle, C.; Saftoiu, A.; Schieler, H.; Schmidt, A.; Schröder,
   F. G.; Sima, O.; Toma, G.; Trinchero, G. C.; Weindl, A.; Wochele,
   J.; Zabierowski, J.; Zensus, J. A.
Bibcode: 2013ICRC...33.1643H
Altcode: 2013arXiv1308.2512H
  One successful detection technique for high-energy cosmic rays is
  based on the radio signal emitted by the charged particles in an
  air shower [1]. The LOPES experiment [2] at Karlsruhe Institute of
  Technology, Germany, has made major contributions to the evolution of
  this technique. LOPES was reconfigured several times to improve and
  further develop the radio detection technique. In the latest setup
  LOPES consisted of 10 tripole antennas. With this, LOPES 3D [3] was
  the first cosmic ray experiment measuring all three vectorial field
  components at once and thereby gaining the full information about the
  electric field vector. We present an analysis based on the data taken
  with special focus on the benefits of a direct measurement of the
  vertical polarization component. We demonstrate that by measuring all
  polarization components the detection and reconstruction efficiency
  is increased and noisy single channel data can be reconstructed by
  utilising the information from the other two channels of one antenna
  station.

Title: A Comparison of LOPES Lateral Distributions of the Air-shower
    Radio Signal with REAS 3.11 and CoREAS Simulations
Authors: Schröder, F. G.; Apel, W. D.; Arteaga-Velázquez, J. C.;
   Bähren, L.; Bekk, K.; Bertaina, M.; Biermann, P. L.; Blümer, J.;
   Bozdog, H.; Brancus, I. M.; Cantoni, E.; Chiavassa, A.; Daumiller,
   K.; de Souza, V.; di Pierro, F.; Doll, P.; Engel, R.; Falcke, H.;
   Fuchs, B.; Fuhrmann, D.; Gemmeke, H.; Grupen, C.; Haungs, A.; Heck,
   D.; Hörandel, J. R.; Horneffer, A.; Huber, D.; Huege, T.; Isar,
   P. G.; Kampert, K. -H.; Kang, D.; Krömer, O.; Kuijpers, J.; Link,
   K.; Łuczak, P.; Ludwig, M.; Mathes, H. J.; Melissas, M.; Morello,
   C.; Oehlschläger, J.; Palmieri, N.; Pierog, T.; Rautenberg, J.;
   Rebel, H.; Roth, M.; Rühle, C.; Saftoiu, A.; Schieler, H.; Schmidt,
   A.; Sima, O.; Toma, G.; Trinchero, G. C.; Weindl, A.; Wochele, J.;
   Zabierowski, J.; Zensus, J. A.
Bibcode: 2013ICRC...33.1589S
Altcode:
  We compare radio lateral distributions measured with LOPES to REAS
  3.11 and CoREAS simulations of the radio emission. These simulation
  codes describe the measured radio signal significantly better than
  previous versions of REAS, which did not yet include the refractive
  index of air. The refractive index changes the coherence conditions
  of the radio emission. This causes flatter lateral distributions at
  LOPES distances (up to a few 100 m). In a few events the amplitude
  even falls towards the shower axis: a behavior which we observe both
  in simulations and measurements. Generally, REAS 3.11 and CoREAS can
  reproduce the measured slope of the lateral distributions within
  the uncertainties. With respect to the absolute amplitude of the
  radio signal, however, there is a difference between REAS 3.11 and
  CoREAS. The amplitude predicted by REAS 3.11 is approximately twice as
  large as the one predicted by CoREAS in frequency range (43 - 74 MHz)
  of LOPES, and REAS 3.11 is closer to the LOPES measurements. Overall,
  the comparison shows that the understanding of the radio emission has
  clearly advanced in the last years. It confirms that in addition to the
  dominant geomagnetic and the sub-dominant Askaryan effect (charge excess
  variation) the refractive index of the air plays an important role.

Title: Comparison of LOPES data and CoREAS Simulations using a Full
    Detector Simulation
Authors: Link, K.; Apel, W. D.; Arteaga-Velazquez, J. C.; Bahren,
   L.; Bekk, K.; Bertaina, M.; Biermann, P. L.; Blumer, J.; Bozdog,
   H.; Brancus, I. M.; Cantoni, E.; Chiavassa, A.; Daumiller, K.; De
   Souza, V.; Di Pierro, F.; Doll, P.; Engel, R.; Falcke, H.; Fuchs, B.;
   Fuhrmann, D.; Gemmeke, H.; Grupen, C.; Haungs, A.; Heck, D.; Horandel,
   J. R.; Horneffer, A.; Huber, D.; Huege, T.; Isar, P. G.; Kampert,
   K. -H.; Kang, D.; Kromer, O.; Kuijpers, J.; Luczak, P.; Ludwig, M.;
   Mathes, H. J.; Melissas, M.; Morello, C.; Oehlschlager, J.; Palmieri,
   N.; Pierog, T.; Rautenberg, J.; Rebel, H.; Roth, M.; Rühle, C.;
   Saftoiu, A.; Schieler, H.; Schmidt, A.; Schroder, F. G.; Sima, O.;
   Toma, G.; Trinchero, G. C.; Weindl, A.; Wochele, J.; Zabierowski,
   J.; Zensus, J. A.
Bibcode: 2013ICRC...33.1705L
Altcode: 2013arXiv1308.2523L
  The LOPES experiment at the Karisruhe Tnstitute of Technology,
  Germany, has been measuring radio emission of air showers for almost 10
  years. For a better understanding of the emission process a detailed
  comparison of data with simulations is necessary. This is possible
  using a newly developed detector simulation including all LOPES
  detector components. After propagating a simulated event through
  this full detector simulation a standard LOPES like event file is
  written. LOPES data and CoREAS simulations can then be treated equally
  and the same analysis software can be applied to both. This gives the
  opportunity to compare data and simulations directly. Furthermore, the
  standard analysis software can be used with simulations which provide
  the possibility to check the accuracy regarding reconstruction of
  air shower parameters. We point out the advantages and present first
  results using such a full LOPES detector simulation. A comparison of
  LOPES data and the Monte Carlo code CoREAS based on an analysis using
  this detector simulation is shown.

Title: Investigation on the Energy and Mass Composition of Cosmic
    Rays Using LOPES Radio Data
Authors: Palmieri, N.; Apel, W. D.; Arteaga-Velázquez, J. C.;
   Bähren, L.; Bekk, K.; Bertaina, M.; Biermann, P. L.; Blümer, J.;
   Bozdog, H.; Brancus, I. M.; Cantoni, E.; Chiavassa, A.; Daumiller,
   K.; de Souza, V.; di Pierro, F.; Doll, P.; Engel, R.; Falcke, H.;
   Fuchs, B.; Fuhrmann, D.; Gemmeke, H.; Grupen, C.; Haungs, A.; Heck,
   D.; Hörandel, J. R.; Horneffer, A.; Huber, D.; Huege, T.; Isar,
   P. G.; Kampert, K. -H.; Kang, D.; Krömer, O.; Kuijpers, J.; Link,
   K.; Łuczak, P.; Ludwig, M.; Mathes, H. J.; Melissas, M.; Morello,
   C.; Oehlschläger, J.; Pierog, T.; Rautenberg, J.; Rebel, H.; Roth,
   M.; Rühle, C.; Saftoiu, A.; Schieler, H.; Schmidt, A.; Schröder,
   F. G.; Sima, O.; Toma, G.; Trinchero, G. C.; Weindl, A.; Wochele,
   J.; Zabierowski, J.; Zensus, J. A.; Lopes Collaboration
Bibcode: 2013ICRC...33..360P
Altcode: 2013arXiv1309.2410P
  The sensitivity to the mass composition as well as the reconstruction of
  the energy of the primary particle are explored here by leveraging the
  features of the radio lateral distribution function. For the purpose
  of this analysis, a set of events measured with the LOPES experiment
  is reproduced with the latest CoREAS radio simulation code. Based on
  simulation predictions, a method which exploits the slope of the radio
  lateral distribution function is developed (Slope Method) and directly
  applied on measurements. As a result, the possibility to reconstruct
  both the energy and the Xmax, i.e. depth of the shower maximum, of
  the cosmic ray air shower using radio data and achieving relatively
  small uncertainties is presented.

Title: Gravitational and Magnetohydrodynamic Waves
Authors: Kuijpers, J.
Bibcode: 2013ASPC..470..197K
Altcode:
  Gravity is known to have important effects on electromagnetic fields
  in the environs of compact objects. After a brief introduction to
  electromagnetism in general relativity, we focus on the interaction
  between gravitational waves (GWs) and magnetohydrodynamic (MHD)
  waves. We use the ideal MHD approximation, and the familiar 1+3 split of
  the reference frame, which allows a direct interpretation of the results
  by the physical observer. We show how fast magneto-sonic waves and
  Alfvén waves can grow in a magneto-plasma by action of gravitational
  waves on the ambient magnetic field in the far-field approximation
  for various configurations of ambient field and wave directions.

Title: LOPES-3D: An antenna array for full signal detection of
    air-shower radio emission
Authors: Apel, W. D.; Arteaga, J. C.; Bähren, L.; Bekk, K.; Bertaina,
   M.; Biermann, P. L.; Blümer, J.; Bozdog, H.; Brancus, I. M.; Buchholz,
   P.; Cantoni, E.; Chiavassa, A.; Daumiller, K.; de Souza, V.; Di Pierro,
   F.; Doll, P.; Engel, R.; Falcke, H.; Finger, M.; Fuchs, B.; Fuhrmann,
   D.; Gemmeke, H.; Grupen, C.; Haungs, A.; Heck, D.; Hörandel, J. R.;
   Horneffer, A.; Huber, D.; Huege, T.; Isar, P. G.; Kampert, K. -H.;
   Kang, D.; Krömer, O.; Kuijpers, J.; Link, K.; Łuczak, P.; Ludwig,
   M.; Mathes, H. J.; Melissas, M.; Morello, C.; Oehlschläger, J.;
   Palmieri, N.; Pierog, T.; Rautenberg, J.; Rebel, H.; Roth, M.; Rühle,
   C.; Saftoiu, A.; Schieler, H.; Schmidt, A.; Schröder, F. G.; Sima,
   O.; Toma, G.; Trinchero, G. C.; Weindl, A.; Wochele, J.; Wommer, M.;
   Zabierowski, J.; Zensus, J. A.
Bibcode: 2012NIMPA.696..100A
Altcode: 2013arXiv1303.6808A
  To better understand the radio signal emitted by extensive
  air-showers and to further develop the radio detection technique
  of high-energy cosmic rays, the LOPES experiment was reconfigured to
  LOPES-3D. LOPES-3D is able to measure all three vectorial components of
  the electric field of radio emission from cosmic ray air showers. The
  additional measurement of the vertical component ought to increase the
  reconstruction accuracy of primary cosmic ray parameters like direction
  and energy, provides an improved sensitivity to inclined showers,
  and will help to validate simulation of the emission mechanisms in
  the atmosphere. LOPES-3D will evaluate the feasibility of vectorial
  measurements for large scale applications. In order to measure all
  three electric field components directly, a tailor-made antenna type
  (tripoles) was deployed. The change of the antenna type necessitated
  new pre-amplifiers and an overall recalibration. The reconfiguration
  and the recalibration procedure are presented and the operationality
  of LOPES-3D is demonstrated.

Title: Experimental evidence for the sensitivity of the air-shower
    radio signal to the longitudinal shower development
Authors: Apel, W. D.; Arteaga, J. C.; Bähren, L.; Bekk, K.; Bertaina,
   M.; Biermann, P. L.; Blümer, J.; Bozdog, H.; Brancus, I. M.; Buchholz,
   P.; Cantoni, E.; Chiavassa, A.; Daumiller, K.; de Souza, V.; Di Pierro,
   F.; Doll, P.; Engel, R.; Falcke, H.; Finger, M.; Fuchs, B.; Fuhrmann,
   D.; Gemmeke, H.; Grupen, C.; Haungs, A.; Heck, D.; Hörandel, J. R.;
   Horneffer, A.; Huber, D.; Huege, T.; Isar, P. G.; Kampert, K. -H.;
   Kang, D.; Krömer, O.; Kuijpers, J.; Link, K.; Łuczak, P.; Ludwig,
   M.; Mathes, H. J.; Melissas, M.; Morello, C.; Oehlschläger, J.;
   Palmieri, N.; Pierog, T.; Rautenberg, J.; Rebel, H.; Roth, M.; Rühle,
   C.; Saftoiu, A.; Schieler, H.; Schmidt, A.; Schröder, F. G.; Sima,
   O.; Toma, G.; Trinchero, G. C.; Weindl, A.; Wochele, J.; Wommer, M.;
   Zabierowski, J.; Zensus, J. A.
Bibcode: 2012PhRvD..85g1101A
Altcode: 2012arXiv1203.3971A
  We observe a correlation between the slope of radio lateral
  distributions and the mean muon pseudorapidity of 59 individual
  cosmic-ray-air-shower events. The radio lateral distributions are
  measured with LOPES, a digital radio interferometer colocated with
  the multidetector-air-shower array KASCADE-Grande, which includes a
  muon-tracking detector. The result proves experimentally that radio
  measurements are sensitive to the longitudinal development of cosmic-ray
  air showers. This is one of the main prerequisites for using radio
  arrays for ultra-high-energy particle physics and astrophysics.

Title: The evolution of ultracompact X-ray binaries
Authors: van Haaften, L. M.; Nelemans, G.; Voss, R.; Wood, M. A.;
   Kuijpers, J.
Bibcode: 2012A&A...537A.104V
Altcode: 2011arXiv1111.5978V
  Context. Ultracompact X-ray binaries (UCXBs) typically consist of
  a white dwarf donor and a neutron star or black hole accretor. The
  evolution of UCXBs and very low mass ratio binaries in general is poorly
  understood. In particular, the dynamical behavior of an accretion disk
  extending to a large radius (relative to the orbit) is unclear. <BR />
  Aims: We investigate the evolution of UCXBs in order to learn for which
  mass ratios and accretor types these systems can exist, and if they do,
  what are their orbital and neutron star spin periods, mass transfer
  rates and evolutionary timescales. <BR /> Methods: We compute tracks
  of a binary containing a Roche-lobe overflowing helium white dwarf
  in which mass transfer is driven by gravitational wave emission. For
  different assumptions concerning accretion disk behavior we calculate
  for which system parameters dynamical instability, thermal-viscous
  disk instability or the propeller effect emerge. The significance of
  these processes during the evolution of an UCXB is considered. <BR
  /> Results: At the onset of mass transfer, the survival of the UCXB
  is determined by how efficiently the accretor can eject matter in
  the case of a super-Eddington mass transfer rate. At later times,
  the evolution of systems strongly depends on the binary's capacity to
  return angular momentum from the disk to the orbit. We find that this
  feedback mechanism most likely remains effective even at very low mass
  ratio. In the case of steady mass transfer, the propeller effect can
  stop accretion onto recycled neutron stars completely at a sufficiently
  low mass transfer rate, based on energy considerations. However, mass
  transfer will likely be non-steady because disk instability allows for
  accretion of some of the transferred matter. Together, the propeller
  effect and disk instability cause the low mass ratio UCXBs to be
  visible a small fraction of the time at most, thereby explaining the
  lack of observations of such systems. <BR /> Conclusions: Most likely
  UCXBs avoid late-time dynamically unstable mass loss from the donor
  and continue to evolve as the age of the Universe allows. This implies
  the existence of a large population of low mass ratio binaries with
  orbital periods ~70-80 min, unless some other mechanism has destroyed
  these binaries. Even though none have been discovered yet, black hole
  UCXBs could also exist, at orbital periods of typically 100-110 min.

Title: On noise treatment in radio measurements of cosmic ray
    air showers
Authors: Schröder, F. G.; Apel, W. D.; Arteaga, J. C.; Asch, T.;
   Bähren, L.; Bekk, K.; Bertaina, M.; Biermann, P. L.; Blümer, J.;
   Bozdog, H.; Brancus, I. M.; Buchholz, P.; Buitink, S.; Cantoni,
   E.; Chiavassa, A.; Daumiller, K.; de Souza, V.; Doll, P.; Engel, R.;
   Falcke, H.; Finger, M.; Fuhrmann, D.; Gemmeke, H.; Grupen, C.; Haungs,
   A.; Heck, D.; Hörandel, J. R.; Horneffer, A.; Huber, D.; Huege,
   T.; Isar, P. G.; Kampert, K. -H.; Kang, D.; Krömer, O.; Kuijpers,
   J.; Lafebre, S.; Link, K.; Łuczak, P.; Ludwig, M.; Mathes, H. J.;
   Melissas, M.; Morello, C.; Nehls, S.; Oehlschläger, J.; Palmieri, N.;
   Pierog, T.; Rautenberg, J.; Rebel, H.; Roth, M.; Rühle, C.; Saftoiu,
   A.; Schieler, H.; Schmidt, A.; Sima, O.; Toma, G.; Trinchero, G. C.;
   Weindl, A.; Wochele, J.; Wommer, M.; Zabierowski, J.; Zensus, J. A.
Bibcode: 2012NIMPA.662S.238S
Altcode: 2010arXiv1009.3444S
  Precise measurements of the radio emission by cosmic ray air showers
  require an adequate treatment of noise. Unlike to usual experiments in
  particle physics, where noise always adds to the signal, radio noise
  can in principle decrease or increase the signal if it interferes by
  chance destructively or constructively. Consequently, noise cannot
  simply be subtracted from the signal, and its influence on amplitude
  and time measurement of radio pulses must be studied with care. First,
  noise has to be determined consistently with the definition of the
  radio signal which typically is the maximum field strength of the radio
  pulse. Second, the average impact of noise on radio pulse measurements
  at individual antennas is studied for LOPES. It is shown that a correct
  treatment of noise is especially important at low signal-to-noise
  ratios: noise can be the dominant source of uncertainty for pulse height
  and time measurements, and it can systematically flatten the slope of
  lateral distributions. The presented method can also be transferred
  to other experiments in radio and acoustic detection of cosmic rays
  and neutrinos.

Title: The LOPES experiment—Recent results, status and perspectives
Authors: Huege, T.; Apel, W. D.; Arteaga, J. C.; Asch, T.; Bähren,
   L.; Bekk, K.; Bertaina, M.; Biermann, P. L.; Blümer, J.; Bozdog, H.;
   Brancus, I. M.; Buchholz, P.; Buitink, S.; Cantoni, E.; Chiavassa,
   A.; Daumiller, K.; de Souza, V.; Doll, P.; Engel, R.; Falcke, H.;
   Finger, M.; Fuhrmann, D.; Gemmeke, H.; Grupen, C.; Haungs, A.; Heck,
   D.; Hörandel, J. R.; Horneffer, A.; Huber, D.; Isar, P. G.; Kampert,
   K. -H.; Kang, D.; Krömer, O.; Kuijpers, J.; Lafebre, S.; Link, K.;
   Łuczak, P.; Ludwig, M.; Mathes, H. J.; Melissas, M.; Morello, C.;
   Nehls, S.; Oehlschläger, J.; Palmieri, N.; Pierog, T.; Rautenberg, J.;
   Rebel, H.; Roth, M.; Rühle, C.; Saftoiu, A.; Schieler, H.; Schmidt,
   A.; Schröder, F. G.; Sima, O.; Toma, G.; Trinchero, G. C.; Weindl,
   A.; Wochele, J.; Wommer, M.; Zabierowski, J.; Zensus, J. A.
Bibcode: 2012NIMPA.662S..72H
Altcode: 2010arXiv1009.0345H
  The LOPES experiment at the Karlsruhe Institute of Technology has
  been taking radio data in the frequency range from 40 to 80 MHz
  in coincidence with the KASCADE-Grande air shower detector since
  2003. Various experimental configurations have been employed to study
  aspects such as the energy scaling, geomagnetic dependence, lateral
  distribution, and polarization of the radio emission from cosmic
  rays. The high quality per-event air shower information provided by
  KASCADE-Grande has been the key to many of these studies and has even
  allowed us to perform detailed per-event comparisons with simulations
  of the radio emission. In this article, we give an overview of results
  obtained by LOPES, and present the status and perspectives of the
  ever-evolving experiment.

Title: Thunderstorm observations by air-shower radio antenna arrays
Authors: Apel, W. D.; Arteaga, J. C.; Bähren, L.; Bekk, K.; Bertaina,
   M.; Biermann, P. L.; Blümer, J.; Bozdog, H.; Brancus, I. M.;
   Buchholz, P.; Buitink, S.; Cantoni, E.; Chiavassa, A.; Daumiller, K.;
   de Souza, V.; di Pierro, F.; Doll, P.; Ender, M.; Engel, R.; Falcke,
   H.; Finger, M.; Fuhrmann, D.; Gemmeke, H.; Grupen, C.; Haungs, A.;
   Heck, D.; Hörandel, J. R.; Horneffer, A.; Huber, D.; Huege, T.; Isar,
   P. G.; Kampert, K. -H.; Kang, D.; Krömer, O.; Kuijpers, J.; Link,
   K.; Łuczak, P.; Ludwig, M.; Mathes, H. J.; Melissas, M.; Morello, C.;
   Nehls, S.; Oehlschläger, J.; Palmieri, N.; Pierog, T.; Rautenberg, J.;
   Rebel, H.; Roth, M.; Rühle, C.; Saftoiu, A.; Schieler, H.; Schmidt,
   A.; Schröder, F. G.; Sima, O.; Toma, G.; Trinchero, G. C.; Weindl,
   A.; Wochele, J.; Wommer, M.; Zabierowski, J.; Zensus, J. A.
Bibcode: 2011AdSpR..48.1295A
Altcode: 2013arXiv1303.7068A
  Relativistic, charged particles present in extensive air showers (EAS)
  lead to a coherent emission of radio pulses which are measured to
  identify the shower initiating high-energy cosmic rays. Especially
  during thunderstorms, there are additional strong electric fields
  in the atmosphere, which can lead to further multiplication and
  acceleration of the charged particles and thus have influence on
  the form and strength of the radio emission. For a reliable energy
  reconstruction of the primary cosmic ray by means of the measured
  radio signal it is very important to understand how electric fields
  affect the radio emission. In addition, lightning strikes are a
  prominent source of broadband radio emissions that are visible over
  very long distances. This, on the one hand, causes difficulties in the
  detection of the much lower signal of the air shower. On the other hand
  the recorded signals can be used to study features of the lightning
  development. The detection of cosmic rays via the radio emission and
  the influence of strong electric fields on this detection technique
  is investigated with the LOPES experiment in Karlsruhe, Germany. The
  important question if a lightning is initiated by the high electron
  density given at the maximum of a high-energy cosmic-ray air shower
  is also investigated, but could not be answered by LOPES. But, these
  investigations exhibit the capabilities of EAS radio antenna arrays
  for lightning studies. We report about the studies of LOPES measured
  radio signals of air showers taken during thunderstorms and give a
  short outlook to new measurements dedicated to search for correlations
  of lightning and cosmic rays.

Title: New measurements of cosmic ray air showers with the digital
    radio interferometer LOPES
Authors: Schröder, F. G.; Apel, W. D.; Arteaga, J. C.; Asch, T.;
   Bähren, L.; Bekk, K.; Bertaina, M.; Biermann, P. L.; Blümer, J.;
   Bozdog, H.; Brancus, I. M.; Buchholz, P.; Buitink, S.; Cantoni,
   E.; Chiavassa, A.; Daumiller, K.; de Souza, V.; Doll, P.; Engel, R.;
   Falcke, H.; Finger, M.; Fuhrmann, D.; Gemmeke, H.; Grupen, C.; Haungs,
   A.; Heck, D.; Hörandel, J. R.; Horneffer, A.; Huber, D.; Huege,
   T.; Isar, P. G.; Kampert, K. -H.; Kang, D.; Krömer, O.; Kuijpers,
   J.; Lafebre, S.; Link, K.; Łuczak, P.; Ludwig, M.; Mathes, H. J.;
   Melissas, M.; Morello, C.; Nehls, S.; Oehlschläger, J.; Palmieri, N.;
   Pierog, T.; Rautenberg, J.; Rebel, H.; Roth, M.; Rühle, C.; Saftoiu,
   A.; Schieler, H.; Schmidt, A.; Sima, O.; Toma, G.; Trinchero, G. C.;
   Weindl, A.; Wochele, J.; Wommer, M.; Zabierowski, J.; Zensus, J. A.
Bibcode: 2011ASTRA...7..303S
Altcode:
  LOPES is a digital radio interferometer which measures the
  radio emission of extensive cosmic ray air showers. It mainly
  consists of 30 dipole antennas installed in co-location with
  KASCADE-Grande at the Karlsruhe Institute of Technology (KIT) in
  Germany. KASCADE-Grande measures the secondary air shower particles
  at ground. Whenever KASCADE-Grande detects a high-energy cosmic ray
  event (≳10<SUP>16</SUP> eV), it triggers LOPES which then digitally
  records the radio signal in the frequency band from 40 to 80 MHz. Using
  interferometric methods, LOPES is able to successfully detect air shower
  induced radio pulses, even in the noisy environment at the KIT. In the
  present studies, a considerable progress in understanding the radio
  emission mechanism is shown: The latest version of the "radio emission
  in air shower" simulation program, REAS3, seems to be the first Monte
  Carlo tool which is able to reproduce the magnitude and slope of most
  of the measured lateral distributions.

Title: Measurement of radio emission from extensive air showers
    with LOPES
Authors: Hörandel, J. R.; Apel, W. D.; Arteaga, J. C.; Asch,
   T.; Badea, F.; Bähren, L.; Bekk, K.; Bertaina, M.; Biermann,
   P. L.; Blümer, J.; Bozdog, H.; Brancus, I. M.; Brüggemann, M.;
   Buchholz, P.; Buitink, S.; Cantoni, E.; Chiavassa, A.; Cossavella,
   F.; Daumiller, K.; de Souza, V.; di Pierro, F.; Doll, P.; Ender, M.;
   Engel, R.; Falcke, H.; Finger, M.; Fuhrmann, D.; Gemmeke, H.; Ghia,
   P. L.; Glasstetter, R.; Grupen, C.; Haungs, A.; Heck, D.; Horneffer,
   A.; Huege, T.; Isar, P. G.; Kampert, K. -H.; Kang, D.; Kickelbick,
   D.; Krömer, O.; Kuijpers, J.; Lafebre, S.; Link, K.; Łuczak, P.;
   Ludwig, M.; Mathes, H. J.; Mayer, H. J.; Melissas, M.; Mitrica, B.;
   Morello, C.; Navarra, G.; Nehls, S.; Nigl, A.; Oehlschläger, J.;
   Over, S.; Palmieri, N.; Petcu, M.; Pierog, T.; Rautenberg, J.; Rebel,
   H.; Roth, M.; Saftoiu, A.; Schieler, H.; Schmidt, A.; Schröder, F.;
   Sima, O.; Singh, K.; Toma, G.; Trinchero, G. C.; Ulrich, H.; Weindl,
   A.; Wochele, J.; Wommer, M.; Zabierowski, J.; Zensus, J. A.
Bibcode: 2011NIMPA.630..171H
Altcode: 2009arXiv0911.2371H
  A new method is explored to detect extensive air showers: the
  measurement of radio waves emitted during the propagation of
  the electromagnetic shower component in the magnetic field of
  the Earth. Recent results of the pioneering experiment LOPES are
  discussed. It registers radio signals in the frequency range between 40
  and 80 MHz. The intensity of the measured radio emission is investigated
  as a function of different shower parameters, such as shower energy,
  angle of incidence, and distance to shower axis. In addition, new
  antenna types are developed in the framework of LOPES<SUP>star</SUP>
  and new methods are explored to realize a radio self-trigger algorithm
  in real time.

Title: Prospects for determining air shower characteristics through
    geosynchrotron emission arrival times
Authors: Lafebre, S.; Falcke, H.; Hörandel, J.; Huege, T.; Kuijpers,
   J.
Bibcode: 2010APh....34...12L
Altcode: 2010arXiv1004.0647L
  Using simulations of geosynchrotron radiation from extensive air
  showers, we present a relation between the shape of the geosynchrotron
  radiation front and the distance of the observer to the maximum of the
  air shower. By analyzing the relative arrival times of radio pulses at
  several radio antennas in an air shower array, this relation may be
  employed to estimate the depth of maximum of an extensive air shower
  if its impact position is known, allowing an estimate for the primary
  particle's species. Vice versa, the relation provides an estimate for
  the impact position of the shower's core if an external estimate of the
  depth of maximum is available. In realistic circumstances, the method
  delivers reconstruction uncertainties down to 30 g/cm <SUP>2</SUP>
  when the distance to the shower core does not exceed 7 km. The method
  requires that the arrival direction is known with high precision.

Title: Simulation of radio emission from air showers in atmospheric
    electric fields
Authors: Buitink, S.; Huege, T.; Falcke, H.; Kuijpers, J.
Bibcode: 2010APh....33..296B
Altcode: 2010arXiv1002.4849B
  We study the effect of atmospheric electric fields on the radio pulse
  emitted by cosmic ray air showers. Under fair weather conditions
  the dominant part of the radio emission is driven by the geomagnetic
  field. When the shower charges are accelerated and deflected in an
  electric field additional radiation is emitted. We simulate this effect
  with the Monte Carlo code REAS2, using CORSIKA-simulated showers as
  input. In both codes a routine has been implemented that treats the
  effect of the electric field on the shower particles. We find that the
  radio pulse is significantly altered in background fields of the order
  of ∼100 V/cm and higher. Practically, this means that air showers
  passing through thunderstorms emit radio pulses that are not a reliable
  measure for the shower energy. Under other weather circumstances
  significant electric field effects are expected to occur rarely,
  but nimbostratus clouds can harbor fields that are large enough. In
  general, the contribution of the electric field to the radio pulse
  has polarization properties that are different from the geomagnetic
  pulse. In order to filter out radio pulses that have been affected
  by electric field effects, radio air shower experiments should keep
  weather information and perform full polarization measurements of the
  radio signal.

Title: Monte Carlo simulations of air showers in atmospheric
    electric fields
Authors: Buitink, S.; Huege, T.; Falcke, H.; Heck, D.; Kuijpers, J.
Bibcode: 2010APh....33....1B
Altcode: 2009arXiv0910.5268B
  The development of cosmic ray air showers can be influenced by
  atmospheric electric fields. Under fair weather conditions these
  fields are small, but the strong fields inside thunderstorms can
  have a significant effect on the electromagnetic component of a
  shower. Understanding this effect is particularly important for radio
  detection of air showers, since the radio emission is produced by the
  shower electrons and positrons. We perform Monte Carlo simulations
  to calculate the effects of different electric field configurations
  on the shower development. We find that the electric field becomes
  important for values of the order of 1 kV/cm. Not only can the energy
  distribution of electrons and positrons change significantly for such
  field strengths, it is also possible that runaway electron breakdown
  occurs at high altitudes, which is an important effect in lightning
  initiation.

Title: Observation of a VHE cosmic-ray flare-signal with the L3+C
    muon spectrometer
Authors: Adriani, O.; van den Akker, M.; Aziz, T.; Bähr, J.; Banerjee,
   S.; Becattini, F.; Bellucci, L.; Betev, B. L.; Blaising, J. J.;
   Bobbink, G. J.; Bottai, S.; Bourilkov, D.; Cartacci, A.; Chemarin,
   M.; Chen, G.; Chen, G. M.; Chen, H. S.; Chiarusi, T.; Coignet,
   G.; Ding, L. K.; Duran, I.; Eline, A.; El Mamouni, H.; Faber, G.;
   Fay, J.; Filthaut, F.; Ganguli, S. N.; Gong, Z. F.; Grabosch, H. J.;
   Groenstege, H.; Guo, Y. N.; Gupta, S.; Gurtu, A.; Haller, Ch.; Hayashi,
   Y.; He, Z. X.; Hebbeker, T.; Hervé, A.; Hofer, H.; Hofer, H.; Huo,
   A. X.; Ito, N.; Jing, C. L.; Jones, L. W.; Kantserov, V.; Kawakami,
   S.; Kittel, W.; König, A. C.; Kok, E.; Kuang, H. H.; Kuijpers, J.;
   Ladron de Guevara, P.; Le Coultre, P.; Lei, Y.; Leich, H.; Leiste, R.;
   Li, L.; Li, Z. C.; Liu, Z. A.; Lohmann, W.; Lu, Y. S.; Ma, W. G.; Ma,
   X. H.; Ma, Y. Q.; Mele, S.; Meng, X. W.; Meschini, M.; Metzger, W. J.;
   van Mil, A.; Milcent, H.; Mohanty, G. B.; Monteleoni, B.; Nahnhauer,
   R.; Naumov, V. A.; Nowak, H.; Parriaud, J. -F.; Pauss, F.; Petersen,
   B.; Pieri, M.; Pohl, M.; Pojidaev, V.; Qing, C. R.; Ramelli, R.;
   Ranieri, R.; Ravindran, K. C.; Rewiersma, P.; Riemann, S.; Rojkov,
   A.; Romero, L.; Schmitt, V.; Schoeneich, B.; Schotanus, D. J.; Shen,
   C. Q.; Spillantini, P.; Sulanke, H.; Tang, X. W.; Timmermans, C.;
   Tonwar, S. C.; Trowitzsch, G.; Unger, M.; Verkooijen, H.; van de
   Walle, R. T.; Vogt, H.; Wang, R. G.; Wang, Q.; Wang, X. L.; Wang,
   X. W.; Wang, Z. M.; van Wijk, R.; Wijnen, T. A. M.; Wilkens, H.; Xu,
   Y. P.; Xu, J. S.; Xu, Z. Z.; Yang, C. G.; Yang, X. F.; Yao, Z. G.; Yu,
   Z. Q.; Zhang, C.; Zhang, F.; Zhang, J.; Zhang, S.; Zhou, S. J.; Zhu,
   G. Y.; Zhu, Q. Q.; Zhuang, H. L.; Zwart, A. N. M.; L3+C Collaboration
Bibcode: 2010APh....33...24A
Altcode: 2010APh....33...24T
  The data collected by the L3+C muon spectrometer at the CERN Large
  Electron-Positron collider, LEP, have been used to search for short
  duration signals emitted by cosmic point sources. A sky survey performed
  from July to November 1999 and from April to November 2000 has revealed
  one single flux enhancement (chance probability=2.6×10<SUP>-3</SUP>)
  between the 17th and 20th of August 2000 from a direction with a
  galactic longitude of (265.02 ± 0.42)° and latitude of (55.58 ±
  0.24)°. The energy of the detected muons was above 15 GeV.

Title: Lateral distribution of the radio signal in extensive air
    showers measured with LOPES
Authors: Apel, W. D.; Arteaga, J. C.; Asch, T.; Badea, A. F.; Bähren,
   L.; Bekk, K.; Bertaina, M.; Biermann, P. L.; Blümer, J.; Bozdog, H.;
   Brancus, I. M.; Brüggemann, M.; Buchholz, P.; Buitink, S.; Cantoni,
   E.; Chiavassa, A.; Cossavella, F.; Daumiller, K.; de Souza, V.; di
   Pierro, F.; Doll, P.; Engel, R.; Falcke, H.; Finger, M.; Fuhrmann,
   D.; Gemmeke, H.; Ghia, P. L.; Glasstetter, R.; Grupen, C.; Haungs,
   A.; Heck, D.; Hörandel, J. R.; Horneffer, A.; Huege, T.; Isar, P. G.;
   Kampert, K. -H.; Kang, D.; Kickelbick, D.; Krömer, O.; Kuijpers, J.;
   Lafebre, S.; Łuczak, P.; Ludwig, M.; Mathes, H. J.; Mayer, H. J.;
   Melissas, M.; Mitrica, B.; Morello, C.; Navarra, G.; Nehls, S.; Nigl,
   A.; Oehlschläger, J.; Over, S.; Palmieri, N.; Petcu, M.; Pierog,
   T.; Rautenberg, J.; Rebel, H.; Roth, M.; Saftoiu, A.; Schieler, H.;
   Schmidt, A.; Schröder, F.; Sima, O.; Singh, K.; Toma, G.; Trinchero,
   G. C.; Ulrich, H.; Weindl, A.; Wochele, J.; Wommer, M.; Zabierowski,
   J.; Zensus, J. A.; LOPES Collaboration
Bibcode: 2010APh....32..294A
Altcode: 2009arXiv0910.4866L
  The antenna array LOPES is set up at the location of the KASCADE-Grande
  extensive air shower experiment in Karlsruhe, Germany and aims to
  measure and investigate radio pulses from extensive air showers. The
  coincident measurements allow us to reconstruct the electric
  field strength at observation level in dependence of general EAS
  parameters. In the present work, the lateral distribution of the radio
  signal in air showers is studied in detail. It is found that the lateral
  distributions of the electric field strengths in individual EAS can
  be described by an exponential function. For about 20% of the events
  a flattening towards the shower axis is observed, preferentially for
  showers with large inclination angle. The estimated scale parameters
  R<SUB>0</SUB>, describing the slope of the lateral profiles range
  between 100 and 200 m. No evidence for a direct correlation of
  R<SUB>0</SUB> with shower parameters like azimuth angle, geomagnetic
  angle, or primary energy can be found. This indicates that the lateral
  profile is an intrinsic property of the radio emission during the
  shower development which makes the radio detection technique suitable
  for large scale applications.

Title: LOFAR - A new experiment to record radio emission from cosmic
    particles
Authors: Hörandel, J. R.; Bähren, L.; Buitink, S.; Falcke, H.;
   Horneffer, A.; Kuijpers, J.; Lafèbre, S.; Nigl, A.; Scholten, O.;
   Singh, K.
Bibcode: 2009NuPhS.196..289H
Altcode:
  No abstract at ADS

Title: Air shower measurements with LOFAR
Authors: Horneffer, A.; Bähren, L.; Buitink, S.; Falcke, H.;
   Hörandel, J. R.; Kuijpers, J.; Lafebre, S.; Nigl, A.; Scholten, O.;
   Singh, K.
Bibcode: 2009NIMPA.604S..20H
Altcode: 2009arXiv0903.2398H
  Air showers from cosmic rays emit short, intense radio pulses. The
  Low Frequency Array (LOFAR) is a new radio telescope, that is being
  built in the Netherlands and Europe. Designed primarily as a radio
  interferometer, the core of LOFAR will have a high density of radio
  antennas, which will be extremely well calibrated. This makes LOFAR
  a unique tool for the study of the radio properties of single air
  showers. Triggering on the radio emission from air showers means
  detecting a short radio pulse and discriminating real events from radio
  interference. At LOFAR we plan to search for pulses in the digital
  data stream—either from single antennas or from already beam-formed
  data—and calculate several parameters characterizing the pulse shape
  to pick out real events in a second stage. In addition, we will have
  a small scintillator array to test and confirm the performance of the
  radio only trigger.

Title: Air shower measurements with the LOPES radio antenna array
Authors: Lopes Collaboration; Haungs, A.; Apel, W. D.; Arteaga,
   J. C.; Asch, T.; Auffenberg, J.; Badea, F.; Bähren, L.; Bekk, K.;
   Bertaina, M.; Biermann, P. L.; Blümer, J.; Bozdog, H.; Brancus, I. M.;
   Brüggemann, M.; Buchholz, P.; Buitink, S.; Cantoni, E.; Chiavassa,
   A.; Cossavella, F.; Daumiller, K.; de Souza, V.; di Pierro, F.;
   Doll, P.; Engel, R.; Falcke, H.; Finger, M.; Fuhrmann, D.; Gemmeke,
   H.; Ghia, P. L.; Glasstetter, R.; Grupen, C.; Heck, D.; Hörandel,
   J. R.; Horneffer, A.; Huege, T.; Isar, P. G.; Kampert, K. -H.; Kang,
   D.; Kickelbick, D.; Kolotaev, Y.; Krömer, O.; Kuijpers, J.; Lafebre,
   S.; Łuczak, P.; Mathes, H. J.; Mayer, H. J.; Milke, J.; Mitrica,
   B.; Morello, C.; Navarra, G.; Nehls, S.; Nigl, A.; Oehlschläger,
   J.; Over, S.; Petcu, M.; Pierog, T.; Rautenberg, J.; Rebel, H.; Roth,
   M.; Saftoiu, A.; Schieler, H.; Schmidt, A.; Schröder, F.; Sima, O.;
   Singh, K.; Stümpert, M.; Toma, G.; Trinchero, G. C.; Ulrich, H.;
   Walkowiak, W.; Weindl, A.; Wochele, J.; Wommer, M.; Zabierowski, J.;
   Zensus, J. A.; LOPES Collaboration
Bibcode: 2009NIMPA.604S...1L
Altcode: 2008arXiv0811.1919H
  LOPES is set up at the location of the KASCADE-Grande extensive air
  shower experiment in Karlsruhe, Germany and aims to measure and
  investigate radio pulses from extensive air showers. Since radio
  waves suffer very little attenuation, radio measurements allow the
  detection of very distant or highly inclined showers. These waves can be
  recorded day and night, and provide a bolometric measure of the leptonic
  shower component. LOPES is designed as a digital radio interferometer
  using high bandwidths and fast data processing and profits from the
  reconstructed air shower observables of KASCADE-Grande. The LOPES
  antennas are absolutely amplitude calibrated allowing to reconstruct
  the electric field strength which can be compared with predictions
  from detailed Monte-Carlo simulations. We report about the analysis
  of correlations present in the radio signals measured by the LOPES 30
  antenna array. Additionally, LOPES operates antennas of a different
  type (LOPESSTAR<SUP></SUP>) which are optimized for an application
  at the Pierre Auger Observatory. Status, recent results of the data
  analysis and further perspectives of LOPES and the possible large
  scale application of this new detection technique are discussed.

Title: Universality of electron-positron distributions in extensive
    air showers
Authors: Lafebre, S.; Engel, R.; Falcke, H.; Hörandel, J.; Huege,
   T.; Kuijpers, J.; Ulrich, R.
Bibcode: 2009APh....31..243L
Altcode: 2009arXiv0902.0548L
  Using a large set of simulated extensive air showers, we investigate
  universality features of electron and positron distributions in
  very-high-energy cosmic-ray air showers. Most particle distributions
  depend only on the depth of the shower maximum and the number of
  particles in the cascade at this depth. We provide multi-dimensional
  parameterizations for the electron-positron distributions in
  terms of particle energy, vertical and horizontal momentum angle,
  lateral distance, and time distribution of the shower front. These
  parameterizations can be used to obtain realistic electron-positron
  distributions in extensive air showers for data analysis and simulations
  of Cherenkov radiation, fluorescence signal, and radio emission.

Title: Physics of Drifting Sub-pulses in Radio Pulsars
Authors: Kuijpers, Jan M. E.
Bibcode: 2009ASSL..357..543K
Altcode:
  Sophisticated analysis of single pulses from radio pulsars with
  the most sensitive radio telescopes available have taught us that
  most pulsars exhibit the phenomenon of drifting sub-pulses [43],
  see Figs. 20.1 and 20.2. Already as early as 1970 [41], it has been
  proposed that these ‘marching’ sub-pulses circulate around the
  pulsar magnetic axis, and are caused by short-period waves which form
  part of a long-period wave which circulates about the star at the same
  angular velocity. Let P1 be the rotation period of the pulsar, P2 the
  period between sub-pulses within the primary-pulse envelope, P3 the time
  interval between drifting bands of sub-pulses, and P4 the circulation
  period around the magnetic axis, all expressed in units of time, then
  [41], see Fig. 20.2, 1 P_4 ≈ {{P_1 P_3 } over {P_2 (1 + NP_3 /P_1 )}}
  = {{P_1 P_3 } over {P_2 }} if, in the last equality, the integer N is
  put to zero. After all these years, in a few cases, such a carousel of
  emission columns drifting around the magnetic axis has been constructed
  from the observations [4, 11,12], see Fig. 20.7. Understanding the
  phenomenon of drifting sub-pulses may, therefore, well be crucial to
  our understanding of radio pulsar electrodynamics which despite the
  largely classical nature of the relevant physics is still shrouded in
  mysteries, to date 40 years after the discovery of pulsars.

Title: Study of the solar anisotropy of cosmic ray primaries of
    about 200 GeV energy with the L3+C muon detector
Authors: L3 Collaboration; Achard, P.; Adriani, O.; Aguilar-Benitez,
   M.; van den Akker, M.; Alcaraz, J.; Alemanni, G.; Allaby, J.; Aloisio,
   A.; Alviggi, M. G.; Anderhub, H.; Andreev, V. P.; Anselmo, F.; Arefiev,
   A.; Azemoon, T.; Aziz, T.; Bagnaia, P.; Bajo, A.; Baksay, G.; Baksay,
   L.; Bähr, J.; Baldew, S. V.; Banerjee, S.; Banerjee, Sw.; Barczyk, A.;
   Barillère, R.; Bartalini, P.; Basile, M.; Batalova, N.; Battiston,
   R.; Bay, A.; Becattini, F.; Becker, U.; Behner, F.; Bellucci, L.;
   Berbeco, R.; Berdugo, J.; Berges, P.; Bertucci, B.; Betev, B. L.;
   Biasini, M.; Biglietti, M.; Biland, A.; Blaising, J. J.; Blyth, S. C.;
   Bobbink, G. J.; Böhm, A.; Boldizsar, L.; Borgia, B.; Bottai, S.;
   Bourilkov, D.; Bourquin, M.; Braccini, S.; Branson, J. G.; Brochu,
   F.; Burger, J. D.; Burger, W. J.; Cai, X. D.; Capell, M.; Cara Romeo,
   G.; Carlino, G.; Cartacci, A.; Casaus, J.; Cavallari, F.; Cavallo,
   N.; Cecchi, C.; Cerrada, M.; Chamizo, M.; Chang, Y. H.; Chemarin,
   M.; Chen, A.; Chen, G.; Chen, G. M.; Chen, H. F.; Chen, H. S.;
   Chiarusi, T.; Chiefari, G.; Cifarelli, L.; Cindolo, F.; Clare, I.;
   Clare, R.; Coignet, G.; Colino, N.; Costantini, S.; de la Cruz, B.;
   Cucciarelli, S.; de Asmundis, R.; Déglon, P.; Debreczeni, J.; Degré,
   A.; Dehmelt, K.; Deiters, K.; della Volpe, D.; Delmeire, E.; Denes, P.;
   DeNotaristefani, F.; De Salvo, A.; Diemoz, M.; Dierckxsens, M.; Ding,
   L. K.; Dionisi, C.; Dittmar, M.; Doria, A.; Dova, M. T.; Duchesneau,
   D.; Duda, M.; Duran, I.; Echenard, B.; Eline, A.; El Mamouni, H.;
   Engler, A.; Eppling, F. J.; Extermann, P.; Faber, G.; Falagan, M. A.;
   Falciano, S.; Favara, A.; Fay, J.; Fedin, O.; Felcini, M.; Ferguson,
   T.; Fiandrini, E.; Field, J. H.; Filthaut, F.; Fisher, W.; Forconi,
   G.; Freudenreich, K.; Furetta, C.; Galaktionov, Yu.; Ganguli, S. N.;
   Garcia-Abia, P.; Gataullin, M.; Gentile, S.; Giagu, S.; Gong, Z. F.;
   Grabosch, H. J.; Grenier, G.; Grimm, O.; Groenstege, H.; Gruenewald,
   M. W.; Guo, Y. N.; Gupta, S.; Gupta, V. K.; Gurtu, A.; Gutay, L. J.;
   Haas, D.; Haller, Ch.; Hatzifotiadou, D.; Hayashi, Y.; He, Z. X.;
   Hebbeker, T.; Hervé, A.; Hirschfelder, J.; Hofer, H.; Hoferjun, H.;
   Hohlmann, M.; Holzner, G.; Hou, S. R.; Huo, A. X.; Ito, N.; Jin, B. N.;
   Jindal, P.; Jing, C. L.; Jones, L. W.; de Jong, P.; Josa-Mutuberría,
   I.; Kantserov, V.; Kaur, M.; Kawakami, S.; Kienzle-Focacci, M. N.;
   Kim, J. K.; Kirkby, J.; Kittel, W.; Klimentov, A.; König, A. C.;
   Kok, E.; Korn, A.; Kopal, M.; Koutsenko, V.; Kräber, M.; Kuang,
   H. H.; Kraemer, R. W.; Krüger, A.; Kuijpers, J.; Kunin, A.; Ladron
   de Guevara, P.; Laktineh, I.; Landi, G.; Lebeau, M.; Lebedev, A.;
   Lebrun, P.; Lecomte, P.; Lecoq, P.; Le Coultre, P.; Le Goff, J. M.;
   Lei, Y.; Leich, H.; Leiste, R.; Levtchenko, M.; Levtchenko, P.; Li,
   C.; Li, L.; Li, Z. C.; Likhoded, S.; Lin, C. H.; Lin, W. T.; Linde,
   F. L.; Lista, L.; Liu, Z. A.; Lohmann, W.; Longo, E.; Lu, Y. S.; Luci,
   C.; Luminari, L.; Lustermann, W.; Ma, W. G.; Ma, X. H.; Ma, Y. Q.;
   Malgeri, L.; Malinin, A.; Maña, C.; Mans, J.; Martin, J. P.; Marzano,
   F.; Mazumdar, K.; McNeil, R. R.; Mele, S.; Meng, X. W.; Merola, L.;
   Meschini, M.; Metzger, W. J.; Mihul, A.; van Mil, A.; Milcent, H.;
   Mirabelli, G.; Mohanty, G. B.; Monteleoni, B.; Muanza, G. S.; Muijs,
   A. J. M.; Musy, M.; Nagy, S.; Nahnhauer, R.; Naumov, V. A.; Natale,
   S.; Napolitano, M.; Nessi-Tedaldi, F.; Newman, H.; Nisati, A.; Novak,
   T.; Nowak, H.; Ofierzynski, R.; Organtini, G.; Pal, I.; Palomares,
   C.; Paolucci, P.; Paramatti, R.; Parriaud, J. -F.; Passaleva, G.;
   Patricelli, S.; Paul, T.; Pauluzzi, M.; Paus, C.; Pauss, F.; Pedace,
   M.; Pensotti, S.; Perret-Gallix, D.; Petersen, B.; Piccolo, D.;
   Pierella, F.; Pieri, M.; Pioppi, M.; Piroué, P. A.; Pistolesi, E.;
   Plyaskin, V.; Pohl, M.; Pojidaev, V.; Pothier, J.; Prokofiev, D.;
   Qing, C. R.; Rahal-Callot, G.; Rahaman, M. A.; Raics, P.; Raja, N.;
   Ramelli, R.; Rancoita, P. G.; Ranieri, R.; Raspereza, A.; Ravindran,
   K. C.; Razis, P.; Rembeczki, S.; Ren, D.; Rescigno, M.; Reucroft,
   S.; Rewiersma, P.; Riemann, S.; Riles, K.; Roe, B. P.; Rojkov, A.;
   Romero, L.; Rosca, A.; Rosier-Lees, S.; Roth, S.; Rubio, J. A.;
   Ruggiero, G.; Rykaczewski, H.; Saidi, R.; Sakharov, A.; Saremi, S.;
   Sarkar, S.; Salicio, J.; Sanchez, E.; Schäfer, C.; Schegelsky, V.;
   Schmitt, V.; Schoeneich, B.; Schopper, H.; Schotanus, D. J.; Sciacca,
   C.; Servoli, L.; Shen, C. Q.; Shevchenko, S.; Shivarov, N.; Shoutko,
   V.; Shumilov, E.; Shvorob, A.; Son, D.; Souga, C.; Spillantini, P.;
   Steuer, M.; Stickland, D. P.; Stoyanov, B.; Straessner, A.; Sudhakar,
   K.; Sulanke, H.; Sultanov, G.; Sun, L. Z.; Suter, H.; Swain, J. D.;
   Szillasi, Z.; Tang, X. W.; Tarjan, P.; Tauscher, L.; Taylor, L.;
   Tellili, B.; Teyssier, D.; Timmermans, C.; Ting, Samuel C. C.; Ting,
   S. M.; Tonwar, S. C.; Tóth, J.; Trowitzsch, G.; Tully, C.; Tung,
   K. L.; Ulbricht, J.; Unger, M.; Valente, E.; Verkooijen, H.; Van de
   Walle, R. T.; Vasquez, R.; Vesztergombi, G.; Vetlitsky, I.; Viertel,
   G.; Vivargent, M.; Vlachos, S.; Vodopianov, I.; Vogel, H.; Vogt,
   H.; Vorobiev, I.; Vorobyov, A. A.; Wadhwa, M.; Wang, R. G.; Wang, Q.;
   Wang, X. L.; Wang, X. W.; Wang, Z. M.; Weber, M.; van Wijk, R.; Wijnen,
   T. A. M.; Wilkens, H.; Wynhoff, S.; Xia, L.; Xu, Y. P.; Xu, J. S.; Xu,
   Z. Z.; Yamamoto, J.; Yang, B. Z.; Yang, C. G.; Yang, H. J.; Yang, M.;
   Yang, X. F.; Yao, Z. G.; Yeh, S. C.; Yu, Z. Q.; Zalite, An.; Zalite,
   Yu.; Zhang, C.; Zhang, F.; Zhang, J.; Zhang, S.; Zhang, Z. P.; Zhao,
   J.; Zhou, S. J.; Zhu, G. Y.; Zhu, R. Y.; Zhu, Q. Q.; Zhuang, H. L.;
   Zichichi, A.; Zimmermann, B.; Zöller, M.; Zwart, A. N. M.
Bibcode: 2008A&A...488.1093L
Altcode:
  Context: Primary cosmic rays experience multiple deflections in
  the non-uniform galactic and heliospheric magnetic fields which may
  generate anisotropies. <BR />Aims: A study of anisotropies in the
  energy range between 100 and 500 GeV is performed. This energy range
  is not yet well explored. <BR />Methods: The L3 detector at the CERN
  electron-positron collider, LEP, is used for a study of the angular
  distribution of atmospheric muons with energies above 20 GeV. This
  distribution is used to investigate the isotropy of the time-dependent
  intensity of the primary cosmic-ray flux with a Fourier analysis. <BR
  />Results: A small deviation from isotropy at energies around 200
  GeV is observed for the second harmonics at the solar frequency. No
  sidereal anisotropy is found at a level above 10<SUP>-4</SUP>. The
  measurements were performed in the years 1999 and 2000.

Title: Frequency spectra of cosmic ray air shower radio emission
    measured with LOPES
Authors: Nigl, A.; Apel, W. D.; Arteaga, J. C.; Asch, T.; Auffenberg,
   J.; Badea, F.; Bähren, L.; Bekk, K.; Bertaina, M.; Biermann, P. L.;
   Blümer, J.; Bozdog, H.; Brancus, I. M.; Brüggemann, M.; Buchholz,
   P.; Buitink, S.; Butcher, H.; Cantoni, E.; Chiavassa, A.; Cossavella,
   F.; Daumiller, K.; de Souza, V.; di Pierro, F.; Doll, P.; Engel,
   R.; Falcke, H.; Gemmeke, H.; Ghia, P. L.; Glasstetter, R.; Grupen,
   C.; Haungs, A.; Heck, D.; Hörandel, J. R.; Horneffer, A.; Huege,
   T.; Isar, P. G.; Kampert, K. -H.; Kickelbick, D.; Kolotaev, Y.;
   Krömer, O.; Kuijpers, J.; Lafebre, S.; Łuczak, P.; Manewald, M.;
   Mathes, H. J.; Mayer, H. J.; Meurer, C.; Mitrica, B.; Morello, C.;
   Navarra, G.; Nehls, S.; Oehlschläger, J.; Ostapchenko, S.; Over, S.;
   Petcu, M.; Pierog, T.; Rautenberg, J.; Rebel, H.; Roth, M.; Saftoiu,
   A.; Schieler, H.; Schmidt, A.; Schröder, F.; Sima, O.; Singh, K.;
   Stümpert, M.; Toma, G.; Trinchero, G. C.; Ulrich, H.; van Buren, J.;
   Walkowiak, W.; Weindl, A.; Wochele, J.; Zabierowski, J.; Zensus, J. A.
Bibcode: 2008A&A...488..807N
Altcode: 2008arXiv0809.2751N
  Aims: We wish to study the spectral dependence of the radio emission
  from cosmic-ray air showers around 100 PeV (10<SUP>17</SUP> eV). <BR
  />Methods: We observe short radio pulses in a broad frequency band
  with the dipole-interferometer LOPES (LOFAR Prototype Station), which
  is triggered by a particle detector array named Karlsruhe Shower Core
  and Array Detector (KASCADE). LOFAR is the Low Frequency Array. For this
  analysis, 23 strong air shower events are selected using parameters from
  KASCADE. The radio data are digitally beam-formed before the spectra are
  determined by sub-band filtering and fast Fourier transformation. <BR
  />Results: The resulting electric field spectra fall off to higher
  frequencies. An average electric field spectrum is fitted with an
  exponential E<SUB>ν</SUB>=K\cdotexp (ν/MHz/β) and β=-0.017±0.004,
  or alternatively, with a power law ɛ<SUB>ν</SUB>=K\cdotν<SUP>α</SUP>
  and a spectral index of α=-1±0.2. The spectral slope obtained is
  not consistent within uncertainties and it is slightly steeper than
  the slope obtained from Monte Carlo simulations based on air showers
  simulated with CORSIKA (Cosmic Ray Simulations for KASCADE). For
  the analyzed sample of LOPES events, we do not find any significant
  dependence of the spectral slope on the electric field amplitude,
  the azimuth angle, the zenith angle, the curvature radius, nor on the
  average distance of the antennae from the shower core position. But
  one of the strongest events was measured during thunderstorm activity
  in the vicinity of LOPES and shows the longest pulse length measured
  of 110 ns and a spectral slope of α=-3.6. <BR />Conclusions: We show
  with two different methods that frequency spectra from air shower
  radio emission can be reconstructed on event-by-event basis, with
  only two dozen dipole antennae simultaneously over a broad range of
  frequencies. According to the obtained spectral slopes, the maximum
  power is emitted below 40 MHz. Furthermore, the decrease in power to
  higher frequencies indicates a loss in coherence determined by the
  shower disc thickness. We conclude that a broader bandwidth, larger
  collecting area, and longer baselines, as will be provided by LOFAR, are
  necessary to further investigate the relation of the coherence, pulse
  length, and spectral slope of cosmic ray air showers. <P />Table 2 and
  Fig. 14 are only available in electronic form at http://www.aanda.org

Title: Direction identification in radio images of cosmic-ray air
    showers detected with LOPES and KASCADE
Authors: Nigl, A.; Apel, W. D.; Arteaga, J. C.; Asch, T.; Auffenberg,
   J.; Badea, F.; Bähren, L.; Bekk, K.; Bertaina, M.; Biermann, P. L.;
   Blümer, J.; Bozdog, H.; Brancus, I. M.; Brüggemann, M.; Buchholz,
   P.; Buitink, S.; Butcher, H.; Cantoni, E.; Chiavassa, A.; Cossavella,
   F.; Daumiller, K.; de Souza, V.; di Pierro, F.; Doll, P.; Engel,
   R.; Falcke, H.; Gemmeke, H.; Ghia, P. L.; Glasstetter, R.; Grupen,
   C.; Haungs, A.; Heck, D.; Hörandel, J. R.; Horneffer, A.; Huege,
   T.; Isar, P. G.; Kampert, K. -H.; Kickelbick, D.; Kolotaev, Y.;
   Krömer, O.; Kuijpers, J.; Lafebre, S.; Łuczak, P.; Manewald, M.;
   Mathes, H. J.; Mayer, H. J.; Meurer, C.; Mitrica, B.; Morello, C.;
   Navarra, G.; Nehls, S.; Oehlschläger, J.; Ostapchenko, S.; Over, S.;
   Petcu, M.; Pierog, T.; Rautenberg, J.; Rebel, H.; Roth, M.; Saftoiu,
   A.; Schieler, H.; Schmidt, A.; Schröder, F.; Sima, O.; Singh, K.;
   Stümpert, M.; Toma, G.; Trinchero, G. C.; Ulrich, H.; van Buren, J.;
   Walkowiak, W.; Weindl, A.; Wochele, J.; Zabierowski, J.; Zensus, J. A.
Bibcode: 2008A&A...487..781N
Altcode: 2008arXiv0809.2742N
  Aims: We want to understand the emission mechanism of radio emission
  from air showers to determine the origin of high-energy cosmic
  rays. Therefore, we study the geometry of the air shower radio emission
  measured with LOPES and search for systematic effects between the
  direction determined on the radio signal and the direction provided by
  the particle detector array KASCADE. <BR />Methods: We produce 4D radio
  images on time-scales of nanoseconds using digital beam-forming. Each
  pixel of the image is calculated for three spatial dimensions and
  as a function of time. The third spatial dimension is obtained by
  calculating the beam focus for a range of curvature radii fitted to
  the signal wave front. We search this multi-dimensional parameter space
  for the direction of maximum coherence of the air shower radio signal
  and compare it to the direction provided by KASCADE. <BR />Results:
  The maximum radio emission of air showers is obtained for curvature
  radii being larger than 3 km. We find that the direction of the emission
  maximum can change when optimizing the curvature radius. This dependence
  dominates the statistical uncertainty for the direction determination
  with LOPES. Furthermore, we find a tentative increase of the curvature
  radius to lower elevations, where the air showers pass through a
  larger atmospheric depth. The distribution of the offsets between
  the directions of both experiments is found to decrease linearly with
  increasing signal-to-noise ratio. Significantly increased offsets and
  enhanced signal strengths are found in events which were modified by
  strong electric fields in thunderstorm clouds. <BR />Conclusions:
  We conclude that the angular resolution of LOPES is sufficient to
  determine the direction which maximizes the observed electric field
  amplitude. However, the statistical uncertainty of the directions is
  not determined by the resolution of LOPES, but by the uncertainty of
  the curvature radius. We do not find any systematic deviation between
  the directions determined from the radio signal and from the detected
  particles. This result places a strong supportive argument for the use
  of the radio technique to study the origin of high-energy cosmic rays.

Title: Prospects for direct cosmic ray mass measurements through
    the Gerasimova-Zatsepin effect
Authors: Lafèbre, S.; Falcke, H.; Hörandel, J.; Kuijpers, J.
Bibcode: 2008A&A...485....1L
Altcode: 2008arXiv0804.2633L
  Context: The solar radiation field may break ultra-high-energy cosmic
  nuclei apart, after which both remnants will be deflected in the
  interplanetary magnetic field in different ways. This process is
  known as the Gerasimova-Zatsepin effect after its discoverers. <BR
  />Aims: We investigate the possibility of using the detection of
  the separated air showers produced by a pair of remnant particles
  as a way to identify the species of the original cosmic ray primary
  directly. Event rates for current and proposed detectors are estimated,
  and requirements are defined for ideal detectors of this phenomenon. <BR
  />Methods: Detailed computational models of the disintegration and
  deflection processes for a wide range of cosmic ray primaries in the
  energy range of 10<SUP>16</SUP> to 10<SUP>20</SUP> eV were combined
  with sophisticated detector models to calculate realistic detection
  rates. <BR />Results: The fraction of Gerasimova-Zatsepin events is
  found to be approximately 10<SUP>-5</SUP> of the cosmic ray flux,
  implying an intrinsic event rate of around 0.07 km<SUP>-2</SUP>
  sr<SUP>-1</SUP> yr<SUP>-1</SUP> in the defined energy range. Event
  rates in any real experiment, whether existing or under construction,
  will probably not exceed 10<SUP>-2</SUP> yr<SUP>-1</SUP>.

Title: Primary Particle Energy Calibration of the EAS Radio Pulse
    Height
Authors: Horneffer, A.; Apel, W. D.; Arteaga, J. C.; Asch, T.;
   Auffenberg, J.; Badea, F.; Bähren, L.; Bekk, K.; Bertaina, M.;
   Biermann, P. L.; Blümer, J.; Bozdog, H.; Brancus, I. M.; Brüggemann,
   M.; Buchholz, P.; Buitink, S.; Butcher, H.; Chiavassa, A.; Cossavella,
   F.; Daumiller, K.; de Souza, V.; Di Pierro, F.; Doll, P.; Engel,
   R.; Falcke, H.; Gemmeke, H.; Ghia, P. L.; Glasstetter, R.; Grupen,
   C.; Haungs, A.; Heck, D.; Hörandel, J. R.; Huege, T.; Isar, P. G.;
   Kampert, K. -H.; Kickelbick, D.; Kolotaev, Y.; Krömer, O.; Kuijpers,
   J.; Lafebre, S.; Luczak, P.; Mathes, H. J.; Mayer, H. J.; Meurer,
   C.; Milke, J.; Mitrica, B.; Morello, C.; Navarra, G.; Nehls, S.;
   Nigl, A.; Oehlschläger, J.; Ostapchenko, S.; Over, S.; Petcu, M.;
   Petrovic, J.; Pierog, T.; Plewina, S.; Rautenberg, J.; Rebel, H.;
   Roth, M.; Schieler, H.; Sima, O.; Singh, K.; Stümpert, M.; Toma, G.;
   Trinchero, G. C.; Ulrich, H.; van Buren, J.; Walkowiak, W.; Weindl,
   A.; Wochele, J.; Zabierowski, J.; Zensus, J. A.
Bibcode: 2008ICRC....4...83H
Altcode: 2008ICRC...30d..83H
  LOPES is one the pioneering experiments for the measurement of radio
  emission from air showers with digital radio receivers. It is set up
  at the site of the KASCADE-Grande air shower array and takes data in
  conjunction with it. This gives us the unique possibility to combine
  LOPES and KASCADE-Grande data. In its second phase LOPES has been
  extended to 30 antennas, which increases the detection rate of well
  reconstructed events. Also a new, absolute calibration of the radio
  antennas is now available. By correlating the measured radio pulse
  height with air shower parameters measured by KASCADE-Grande, we have
  derived a formula that describes the radio pulse height as a function
  of air shower geometry and primary particle energy. Thus allowing us
  to estimate the cosmic ray energy from radio data.

Title: The LOFAR air shower front evolution library
Authors: Lafebre, S.; Huege, T.; Falcke, H.; Kuijpers, J.
Bibcode: 2008ICRC....4..577L
Altcode: 2008ICRC...30d.577L
  The LOFAR radio telescope, under construction in the Netherlands,
  will be a powerful instrument to measure extensive air showers through
  their radio signal. In order to fully understand the properties of
  these signals, we are building a library of CORSIKA simulations of
  showers at 10<SUP>16</SUP>--10<SUP>20.5</SUP> eV on the LOFAR BlueGene
  supercomputer. This library contains histogrammed data on the particle
  energy and spatial and angular distributions throughout the course of
  the air showers. The REAS2 code is used to calculate geosynchrotron
  radio emission from these simulations. We present parametrisations of
  various characteristics of the particle distributions and radio signal
  from showers in this library.

Title: Update on radio detection of inclined air showers with LOPES-10
Authors: Săftoiu, A.; Apel, W. D.; Arteaga, J. C.; Asch, T.;
   Auffenberg, J.; Badea, F.; Bähren, L.; Bekk, K.; Bertaina, M.;
   Biermann, P. L.; Blümer, J.; Bozdog, H.; Brancus, I. M.; Brüggemann,
   M.; Buchholz, P.; Buitink, S.; Butcher, H.; Chiavassa, A.; Cossavella,
   F.; Daumiller, K.; de Souza, V.; Di Pierro, F.; Doll, P.; Engel,
   R.; Falcke, H.; Gemmeke, H.; Ghia, P. L.; Glasstetter, R.; Grupen,
   C.; Haungs, A.; Heck, D.; Hörandel, J. R.; Horneffer, A.; Huege, T.;
   Isar, P. G.; Kampert, K. -H.; Kickelbick, D.; Kolotaev, Y.; Krömer,
   O.; Kuijpers, J.; Lafebre, S.; Luczak, P.; Mathes, H. J.; Mayer,
   H. J.; Meurer, C.; Milke, J.; Mitrica, B.; Morello, C.; Navarra, G.;
   Nehls, S.; Nigl, A.; Oehlschläger, J.; Ostapchenko, S.; Over, S.;
   Petcu, M.; Petrovic, J.; Pierog, T.; Plewnia, S.; Rautenberg, J.;
   Rebel, H.; Roth, M.; Schieler, H.; Sima, O.; Singh, K.; Stümpert,
   M.; Toma, G.; Trinchero, G. C.; Ulrich, H.; van Buren, J.; Walkowiak,
   W.; Weindl, A.; Wochele, J.; Zabierowski, J.; Zensus, J. A.
Bibcode: 2008ICRC....4..231S
Altcode: 2008ICRC...30d.231S
  Inclined air showers are a particularly interesting target for
  observation with the radio technique. They are expected to be well
  detectable and allow analyses of angular correlations over a much
  broader range in geomagnetic angle than near-vertical events. We
  present an updated analysis of highly inclined (&gt;50° zenith
  angle), high energy (&gt;10<SUP>5</SUP> N_mu) air showers measured
  with KASCADE-Grande in coincidence with LOPES-10. Data from the
  Grande rather than the KASCADE array are used for the reconstruction
  of the air shower events, giving us access to a broader range of core
  distances for an independent cross-check with the earlier analysis.

Title: Investigations of the lateral extension of radio emission in
    air showers by LOPES30 measurements
Authors: Nehls, S.; Apel, W. D.; Arteaga, J. C.; Asch, T.; Auffenberg,
   J.; Badea, F.; Bähren, L.; Bekk, K.; Bertaina, M.; Biermann, P. L.;
   Blümer, J.; Bozdog, H.; Brancus, I. M.; Brüggemann, M.; Buchholz, P.;
   Butcher, H.; Chiavassa, A.; Cossavella, F.; Daumiller, K.; de Souza,
   V.; Di Pierro, F.; Doll, P.; Engel, R.; Falcke, H.; Gemmeke, H.; Ghia,
   P. L.; Glasstetter, R.; Grupen, C.; Haungs, A.; Heck, D.; Hörandel,
   J. R.; Horneffer, A.; Huege, T.; Isar, P. G.; Kampert, K. -H.;
   Kickelbick, D.; Kolotaev, Y.; Krömer, O.; Kuijpers, J.; Lafebre,
   S.; Luczak, P.; Mathes, H. J.; Mayer, H. J.; Meurer, C.; Milke,
   J.; Mitrica, B.; Morello, C.; Navarra, G.; Nigl, A.; Oehlschläger,
   J.; Ostapchenko, S.; Over, S.; Petcu, M.; Petrovic, J.; Pierog, T.;
   Plewnia, S.; Rautenberg, J.; Rebel, H.; Roth, M.; Schieler, H.; Sima,
   O.; Singh, K.; Stümpert, M.; Toma, G.; Trinchero, G. C.; Ulrich,
   H.; van Buren, J.; Walkowiak, W.; Weindl, Wochele, J.; Zabierowski,
   J.; Zensus, J. A.
Bibcode: 2008ICRC....4..131N
Altcode: 2008ICRC...30d.131N
  LOPES30 is a digital radio antenna array working in the frequency
  range 40 -- 80 MHz with 30 dipole antennas triggered by the air
  shower experiment KASCADE-Grande. From an absolute calibration the
  measured field strength of the LOPES30 antenna system is known and
  the invesitigation of a large data set taken in east-west polarisation
  is performed. The reconstructed pulse height of the radio emission in
  extensive air showers is the measured quantity to be compared with the
  KASCADE-Grande reconstruction parameters, like primary energy or shower
  geometrie on a single air hower basis. The resulting correlations
  will also be compared with expectations from detailed Monte Carlo
  simulations.

Title: Shower evolution and radio emission of air showers in
    thunderstorm electric fields
Authors: Buitink, S.; Apel, W. D.; Arteaga, J. C.; Asch, T.;
   Auffenberg, J.; Badea, F.; Bähren, L.; Bekk, K.; Bertaina, M.;
   Biermann, P. L.; Blümer, J.; Bozdog, H.; Brancus, I. M.; Brüggemann,
   M.; Buchholz, P.; Butcher, H.; Chiavassa, A.; Cossavella, F.;
   Daumiller, K.; de Souza, V.; Di Pierro, F.; Doll, P.; Engel, R.;
   Falcke, H.; Gemmeke, H.; Ghia, P. L.; Glasstetter, R.; Grupen, C.;
   Haungs, A.; Heck, D.; Hörandel, J. R.; Horneffer, A.; Huege, T.; Isar,
   P. G.; Kampert, K. -H.; Kickelbick, D.; Kolotaev, Y.; Krömer, O.;
   Kuijpers, J.; Lafebre, S.; Luczak, P.; Mathes, H. J.; Mayer, H. J.;
   Meurer, C.; Milke, J.; Mitrica, B.; Morello, C.; Navarra, G.; Nehls,
   S.; Nigl, A.; Oehlschläger, J.; Ostapchenko, S.; Over, S.; Petcu,
   M.; Petrovic, J.; Pierog, T.; Plewnia, S.; Rautenberg, J.; Rebel, H.;
   Roth, M.; Schieler, H.; Sima, O.; Singh, K.; Stümpert, M.; Toma, G.;
   Trinchero, G. C.; Ulrich, H.; van Buren, J.; Walkowiak, W.; Weindl,
   Wochele, J.; Zabierowski, J.; Zensus, J. A.
Bibcode: 2008ICRC....4..161B
Altcode: 2008ICRC...30d.161B
  The radio emission from cosmic ray air showers consists in large part
  of geosynchrotron radiation. Since the radiation mechanism is based
  on particle acceleration, atmospheric electric fields may play an
  important role. LOPES results show that electric fields under fair
  weather conditions do not alter the radio emission considerably,
  but during thunderstorms strongly amplified pulses are measured. The
  electric field influence on the shower development and radio emission
  is simulated with a modified version of CORSIKA and with REAS2,
  respectively We present results from both data analysis and simulation.

Title: Operation of LOPES-30 for Polarization Measurements of the
    Radio Emission of Cosmic Ray Air Showers
Authors: Isar, P. G.; Apel, W. D.; Arteaga, J. C.; Asch, T.;
   Auffenberg, J.; Badea, F.; Bähren, L.; Bekk, K.; Bertaina, M.;
   Biermann, P. L.; Blümer, J.; Bozdog, H.; Brancus, I. M.; Brüggemann,
   M.; Buchholz, P.; Buitink, S.; Butcher, H.; Chiavassa, A.; Cossavella,
   F.; Daumiller, K.; de Souza, V.; Di Pierro, F.; Doll, P.; Engel,
   R.; Falcke, H.; Gemmeke, H.; Ghia, P. L.; Glasstetter, R.; Grupen,
   C.; Haungs, A.; Heck, D.; Hörandel, J. R.; Horneffer, A.; Huege,
   T.; Kampert, K. -H.; Kickelbick, D.; Kolotaev, Y.; Krömer, O.;
   Kuijpers, J.; Lafebre, S.; Luczak, P.; Mathes, H. J.; Mayer, H. J.;
   Meurer, C.; Milke, J.; Mitrica, B.; Morello, C.; Navarra, G.; Nehls,
   S.; Nigl, A.; Oehlschläger, J.; Ostapchenko, S.; Over, S.; Petcu,
   M.; Petrovic, J.; Pierog, T.; Plewnia, S.; Rautenberg, J.; Rebel, H.;
   Roth, M.; Schieler, H.; Sima, O.; Singh, K.; Stümpert, M.; Toma, G.;
   Trinchero, G. C.; Ulrich, H.; van Buren, J.; Walkowiak, W.; Weindl A.;
   Wochele, J.; Zabierowski, J.; Zensus, J. A.
Bibcode: 2008ICRC....5.1093I
Altcode: 2008ICRC...30e1093I
  The LOPES-30 experiment, located with the air shower experiment
  KASCADE-Grande at Forschungszentrum Karlsruhe, Germany, is an array
  of 30 dipole antennas set-up to investigate the pulsed radio emission
  from cosmic ray air showers in the Earth's atmosphere. After one year of
  measurements of the East-West polarization by all 30 antennas, recently,
  the LOPES-30 set-up was reconfigured to perform dual-polarization
  measurements. Half of the antennas have been configured for measurements
  of the North-South polarization direction. Only by measuring at the
  same time both, the E-W and N-S polarization components of the radio
  emission, the geosynchrotron effect as the dominant emission mechanism
  in air showers can be verified. The status of the measurements,
  including the absolute calibration of the antennas, the monitoring
  of the environmental conditions and a preliminary analysis of the
  dual-polarized events are reported.

Title: VLBI observations of Jupiter with the initial test station
    of LOFAR and the Nançay decametric array
Authors: Nigl, A.; Zarka, P.; Kuijpers, J.; Falcke, H.; Bähren, L.;
   Denis, L.
Bibcode: 2007A&A...471.1099N
Altcode: 2008arXiv0809.2740N
  Aims:To demonstrate and test the capability of the next generation of
  low-frequency radio telescopes to perform high resolution observations
  across intra-continental baselines. Jupiter's strong burst emission
  is used to perform broadband full signal cross-correlations on time
  intervals of up to hundreds of milliseconds. <BR />Methods: Broadband
  VLBI observations at about 20 MHz on a baseline of ~50 000 wavelengths
  were performed to achieve arcsecond angular resolution. lofar's Initial
  Test Station (lofar/its, The Netherlands) and the Nançay Decametric
  Array (nda, France) digitize the measured electric field with 12 bit and
  14 bit in a 40 MHz baseband. The fine structure in Jupiter's signal was
  used for data synchronization prior to correlation on the time-series
  data. <BR />Results: Strong emission from Jupiter was detected during
  snapshots of a few seconds and detailed features down to microsecond
  time-scales were identified in dynamic spectra. Correlations of
  Jupiter's burst emission returned strong fringes on 1 ms time-scales
  over channels as narrow as a hundred kilohertz bandwidth. <BR
  />Conclusions: Long baseline interferometry is confirmed at low
  frequencies, in spite of phase shifts introduced by variations in
  ionospheric propagation characteristics. Phase coherence was preserved
  over tens to hundreds of milliseconds with a baseline of ~700 km. No
  significant variation with time was found in the correlations and an
  estimate for the fringe visibility of 1, suggested that the source was
  not resolved. The upper limit on the source region size of Jupiter Io-B
  S-bursts corresponds to an angular resolution of ~3 arcsec. Adding
  remote stations to the lofar network at baselines up to thousand
  kilometers will provide 10 times higher resolution down to an arcsecond.

Title: Radio Emission in Atmospheric Air Showers: Results of LOPES-10
Authors: Haungs, A.; Apel, W. D.; Asch, T.; Badea, F.; Bähren, L.;
   Bekk, K.; Bercuci, A.; Bertaina, M.; Biermann, P. L.; Blümer, J.;
   Bozdog, H.; Brancus, I. M.; Brüggemann, M.; Buchholz, P.; Buitink,
   S.; Butcher, H.; Chiavassa, A.; Cossavella, F.; Daumiller, K.; Di
   Pierro, F.; Doll, P.; Engel, R.; Falcke, H.; Gemmeke, H.; Ghia, P. L.;
   Glasstetter, R.; Grupen, C.; Hakenjos, A.; Heck, D.; Hörandel, J. R.;
   Horneffer, A.; Huege, T.; Isar, P. G.; Kampert, K. H.; Kolotaev,
   Y.; Krömer, O.; Kuijpers, J.; Lafebre, S.; Mathes, H. J.; Mayer,
   H. J.; Meurer, C.; Milke, J.; Mitrica, B.; Morello, C.; Navarra, G.;
   Nehls, S.; Nigl, A.; Obenland, R.; Oehlschläger, J.; Ostapchenko, S.;
   Over, S.; Petcu, M.; Petrovic, J.; Pierog, T.; Plewnia, S.; Rebel, H.;
   Risse, A.; Roth, M.; Schieler, H.; Sima, O.; Singh, K.; Stümpert, M.;
   Toma, G.; Trinchero, G. C.; Ulrich, H.; van Buren, J.; Walkowiak, W.;
   Weindl, A.; Wochele, J.; Zabierowski, J.; Zensus, J. A.; Zimmermann, D.
Bibcode: 2007JPhCS..81a2005H
Altcode: 2006astro.ph.10553H
  LOPES is set up at the location of the KASCADE-Grande extensive
  air shower experiment in Karlsruhe, Germany and aims to measure and
  investigate radio pulses from Extensive Air Showers. Data taken during
  half a year of operation of 10 LOPES antennas (LOPES-10), triggered
  by showers observed with KASCADE-Grande have been analyzed. We report
  about results of correlations found of the measured radio signals by
  LOPES-10 with shower parameters.

Title: Cosmic rays studied with a hybrid high school detector array
Authors: Nigl, A.; Timmermans, C.; Schellart, P.; Kuijpers, J.;
   Falcke, H.; Horneffer, A.; de Vos, C. M.; Koopman, Y.; Pepping, H. J.;
   Schoonderbeek, G.
Bibcode: 2007ENews..38e..25N
Altcode: 2007ENews..38...25N; 2008arXiv0809.2717N
  The LORUN/NAHSA system is a pathfinder for hybrid cosmic ray research
  combined with education and outreach in the field of astro-particle
  physics. Particle detectors and radio antennae were mainly setup by
  students and placed on public buildings. After fully digital data
  acquisition, coincidence detections were selected. Three candidate
  events confirmed a working prototype, which can be multiplied to extend
  further particle detector arrays on high schools.

Title: Radio Emission in Atmospheric Air Showers: First Measurements
    with LOPES-30
Authors: Isar, P. G.; Nehls, S.; Apel, W. D.; Asch, T.; Badea, F.;
   Bähren, L.; Bekk, K.; Bercuci, A.; Bertaina, M.; Biermann, P. L.;
   Blümer, J.; Bozdog, H.; Brancus, I. M.; Brüggemann, M.; Buchholz,
   P.; Buitink, S.; Butcher, H.; Chiavassa, A.; Cossavella, F.; Daumiller,
   K.; Di Pierro, F.; Doll, P.; Engel, R.; Falcke, H.; Gemmeke, H.; Ghia,
   P. L.; Glasstetter, R.; Grupen, C.; Hakenjos, A.; Haungs, A.; Heck, D.;
   Hörandel, J. R.; Horneffer, A.; Huege, T.; Kampert, K. H.; Kolotaev,
   Y.; Krömer, O.; Kuijpers, J.; Lafebre, S.; Mathes, H. J.; Mayer,
   H. J.; Meurer, C.; Milke, J.; Mitrica, B.; Morello, C.; Navarra, G.;
   Nigl, A.; Obenland, R.; Oehlschläger, J.; Ostapchenko, S.; Over, S.;
   Petcu, M.; Petrovic, J.; Pierog, T.; Plewnia, S.; Rebel, H.; Risse, A.;
   Roth, M.; Schieler, H.; Sima, O.; Singh, K.; Stümpert, M.; Toma, G.;
   Trinchero, G. C.; Ulrich, H.; van Buren, J.; Walkowiak, W.; Weindl,
   A.; Wochele, J.; Zabierowski, J.; Zensus, J. A.; Zimmermann, D.
Bibcode: 2007JPhCS..81a2006I
Altcode: 2006astro.ph.10554I
  When Ultra High Energy Cosmic Rays (UHECR) interact with particles in
  the Earth's atmosphere, they produce a shower of secondary particles
  propagating toward the ground. LOPES-30 is an absolutely calibrated
  array of 30 dipole antennas investigating the radio emission from
  these showers in detail and clarifying if the technique is useful
  for large-scale applications. LOPES-30 is co-located and measures in
  coincidence with the air shower experiment KASCADE-Grande. Status of
  LOPES-30 and first measurements are presented.

Title: Amplified radio emission from cosmic ray air showers in
    thunderstorms
Authors: Buitink, S.; Apel, W. D.; Asch, T.; Badea, F.; Böhren, L.;
   Bekk, K.; Bercuci, A.; Bertaina, M.; Biermann, P. L.; Blümer, J.;
   Bozdog, H.; Brancus, I. M.; Brüggemann, M.; Buchholz, P.; Butcher,
   H.; Chiavassa, A.; Cossavella, F.; Daumiller, K.; di Pierro, F.; Doll,
   P.; Engel, R.; Falcke, H.; Gemmeke, H.; Ghia, P. L.; Glasstetter,
   R.; Grupen, C.; Haungs, A.; Heck, D.; Hörandel, J. R.; Horneffer,
   A.; Huege, T.; Kampert, K. -H.; Kolotaev, Y.; Krömer, O.; Kuijpers,
   J.; Lafebre, S.; Mathes, H. J.; Mayer, H. J.; Meurer, C.; Milke, J.;
   Mitrica, B.; Morello, C.; Navarra, G.; Nehls, S.; Nigl, A.; Obenland,
   R.; Oehlschläger, J.; Ostapchenko, S.; Over, S.; Petcu, M.; Petrovic,
   J.; Pierog, T.; Plewnia, S.; Rebel, H.; Risse, A.; Roth, M.; Schieler,
   H.; Sima, O.; Singh, K.; Stümpert, M.; Toma, G.; Trinchero, G. C.;
   Ulrich, H.; van Buren, J.; Walkowiak, W.; Weindl, A.; Wochele, J.;
   Zabierowski, J.; Zensus, J. A.; Zimmermann, D.
Bibcode: 2007A&A...467..385B
Altcode: 2007astro.ph..2432B
  Context: The detection of radio pulses from cosmic ray air showers is
  a potentially powerful new detection mechanism for studying spectrum
  and composition of ultra high energy cosmic rays that needs to be
  understood in greater detail. The radiation consists in large part
  of geosynchrotron radiation. The intensity of this radiation depends,
  among other factors, on the energy of the primary particle and the angle
  of the shower axis with respect to the geomagnetic field. <BR />Aims:
  Since the radiation mechanism is based on particle acceleration, the
  atmospheric electric field can play an important role. Especially
  inside thunderclouds large electric fields can be present. In
  this paper we examine the contribution of an electric field to the
  emission mechanism theoretically and experimentally. <BR />Methods:
  Two mechanisms of amplification of radio emission are considered:
  the acceleration radiation of the shower particles and the radiation
  from the current that is produced by ionization electrons moving
  in the electric field. For both mechanisms analytical estimates are
  made of their effects on the radio pulse height. We selected lopes
  data recorded during thunderstorms, periods of heavy cloudiness and
  periods of cloudless weather. We tested whether the correlations
  with geomagnetic angle and primary energy vary with atmospheric
  conditions. <BR />Results: We find that during thunderstorms the radio
  emission can be strongly enhanced. The present data suggests that
  the observed amplification is caused by acceleration of the shower
  electrons and positrons. In the near future, extensions of lopes and
  the construction of lofar will help to identify the mechanism in more
  detail. No amplified pulses were found during periods of cloudless sky
  or heavy cloudiness, suggesting that the electric field effect for radio
  air shower measurements can be safely ignored during non-thunderstorm
  conditions.

Title: Anisotropy studies around the galactic centre at EeV energies
    with the Auger Observatory
Authors: Abraham, J.; Aglietta, M.; Aguirre, C.; Allard, D.; Allekotte,
   I.; Allison, P.; Alvarez, C.; Alvarez-Muñiz, J.; Ambrosio, M.;
   Anchordoqui, L.; Anjos, J. C.; Aramo, C.; Arisaka, K.; Armengaud,
   E.; Arneodo, F.; Arqueros, F.; Asch, T.; Asorey, H.; Atulugama,
   B. S.; Aublin, J.; Ave, M.; Avila, G.; Bacelar, J.; Bäcker, T.;
   Badagnani, D.; Barbosa, A. F.; Barbosa, H. M. J.; Barkhausen, M.;
   Barnhill, D.; Barroso, S. L. C.; Bauleo, P.; Beatty, J.; Beau, T.;
   Becker, B. R.; Becker, K. H.; Bellido, J. A.; Benzvi, S.; Berat,
   C.; Bergmann, T.; Bernardini, P.; Bertou, X.; Biermann, P. L.;
   Billoir, P.; Blanch-Bigas, O.; Blanco, F.; Blasi, P.; Bleve, C.;
   Blümer, H.; Boghrat, P.; Boháčová, M.; Bonifazi, C.; Bonino,
   R.; Boratav, M.; Brack, J.; Brunet, J. M.; Buchholz, P.; Busca,
   N. G.; Caballero-Mora, K. S.; Cai, B.; Camin, D. V.; Capdevielle,
   J. N.; Caruso, R.; Castellina, A.; Cataldi, G.; Cazón, L.; Cester,
   R.; Chauvin, J.; Chiavassa, A.; Chinellato, J. A.; Chou, A.; Chye,
   J.; Claes, D.; Clark, P. D. J.; Clay, R. W.; Clay, S. B.; Connolly,
   B.; Cordier, A.; Cotti, U.; Coutu, S.; Covault, C. E.; Cronin, J.;
   Dagoret-Campagne, S.; Quang, T. Dang; Darriulat, P.; Daumiller, K.;
   Dawson, B. R.; de Almeida, R. M.; de Carvalho, L. A.; de Donato, C.;
   de Jong, S. J.; de Mello, W. J. M.; de Mello Neto, J. R. T.; de Mitri,
   I.; de Oliveira, M. A. L.; de Souza, V.; Del Peral, L.; Deligny, O.;
   Della Selva, A.; Delle Fratte, C.; Dembinski, H.; di Giulio, C.; Diaz,
   J. C.; Dobrigkeit, C.; D'Olivo, J. C.; Dornic, D.; Dorofeev, A.; Dova,
   M. T.; D'Urso, D.; Duvernois, M. A.; Engel, R.; Epele, L.; Erdmann, M.;
   Escobar, C. O.; Etchegoyen, A.; Ewers, A.; Facal San Luis, P.; Falcke,
   H.; Fauth, A. C.; Fazio, D.; Fazzini, N.; Fernández, A.; Ferrer, F.;
   Ferry, S.; Fick, B.; Filevich, A.; Filipčič, A.; Fleck, I.; Fokitis,
   E.; Fonte, R.; Fuhrmann, D.; Fulgione, W.; García, B.; Garcia-Pinto,
   D.; Garrard, L.; Garrido, X.; Geenen, H.; Gelmini, G.; Gemmeke, H.;
   Geranios, A.; Ghia, P. L.; Giller, M.; Gitto, J.; Glass, H.; Gobbi, F.;
   Gold, M. S.; Gomez Albarracin, F.; Gómez Berisso, M.; Gómez Herrero,
   R.; Gonçalves Do Amaral, M.; Gongora, J. P.; Gonzalez, D.; Gonzalez,
   J. G.; González, M.; Góra, D.; Gorgi, A.; Gouffon, P.; Grassi, V.;
   Grillo, A.; Grunfeld, C.; Grupen, C.; Guarino, F.; Guedes, G. P.;
   Gutiérrez, J.; Hague, J. D.; Hamilton, J. C.; Harakeh, M. N.; Harari,
   D.; Harmsma, S.; Hartmann, S.; Harton, J. L.; Haungs, A.; Healy,
   M. D.; Hebbeker, T.; Heck, D.; Hojvat, C.; Homola, P.; Hörandel, J.;
   Horneffer, A.; Horvat, M.; Hrabovský, M.; Huege, T.; Iarlori, M.;
   Insolia, A.; Kaducak, M.; Kalashev, O.; Kampert, K. H.; Keilhauer,
   B.; Kemp, E.; Klages, H. O.; Kleifges, M.; Kleinfeller, J.; Knapik,
   R.; Knapp, J.; Koang, D. -H.; Kolotaev, Y.; Kopmann, A.; Krömer,
   O.; Kuhlman, S.; Kuijpers, J.; Kunka, N.; Kusenko, A.; Lachaud, C.;
   Lago, B. L.; Lebrun, D.; Lebrun, P.; Lee, J.; Letessier-Selvon, A.;
   Leuthold, M.; Lhenry-Yvon, I.; Longo, G.; López, R.; Lopez Agüera,
   A.; Lucero, A.; Maldera, S.; Malek, M.; Maltezos, S.; Mancarella,
   G.; Manceñido, M. E.; Mandat, D.; Mantsch, P.; Mariazzi, A. G.;
   Maris, I. C.; Martello, D.; Martinez, N.; Martínez, J.; Martínez,
   O.; Mathes, H. J.; Matthews, J.; Matthews, J. A. J.; Matthiae, G.;
   Maurin, G.; Maurizio, D.; Mazur, P. O.; McCauley, T.; McEwen, M.;
   McNeil, R. R.; Medina, G.; Medina, M. C.; Medina Tanco, G.; Meli, A.;
   Melo, D.; Menichetti, E.; Menshikov, A.; Meurer, Chr.; Meyhandan, R.;
   Micheletti, M. I.; Miele, G.; Miller, W.; Mollerach, S.; Monasor, M.;
   Monnier Ragaigne, D.; Montanet, F.; Morales, B.; Morello, C.; Moreno,
   E.; Morris, C.; Mostafá, M.; Muller, M. A.; Mussa, R.; Navarra, G.;
   Nellen, L.; Newman-Holmes, C.; Newton, D.; Thi, T. Nguyen; Nichol,
   R.; Nierstenhöfer, N.; Nitz, D.; Nogima, H.; Nosek, D.; Nožka,
   L.; Oehlschläger, J.; Ohnuki, T.; Olinto, A.; Oliveira, L. F. A.;
   Olmos-Gilbaja, V. M.; Ortiz, M.; Ostapchenko, S.; Otero, L.; Palatka,
   M.; Pallotta, J.; Parente, G.; Parizot, E.; Parlati, S.; Patel, M.;
   Paul, T.; Payet, K.; Pech, M.; PeĶala, J.; Pelayo, R.; Pepe, I. M.;
   Perrone, L.; Petrera, S.; Petrinca, P.; Petrov, Y.; Pham Ngoc, D.;
   Pham Thi, T. N.; Piegaia, R.; Pierog, T.; Pisanti, O.; Porter, T. A.;
   Pouryamout, J.; Prado, L.; Privitera, P.; Prouza, M.; Quel, E. J.;
   Rautenberg, J.; Reis, H. C.; Reucroft, S.; Revenu, B.; Řídký, J.;
   Risi, A.; Risse, M.; Rivière, C.; Rizi, V.; Robbins, S.; Roberts, M.;
   Robledo, C.; Rodriguez, G.; Rodríguez Frías, D.; Rodriguez Martino,
   J.; Rodriguez Rojo, J.; Ros, G.; Rosado, J.; Roth, M.; Roucelle,
   C.; Rouillé-D'Orfeuil, B.; Roulet, E.; Rovero, A. C.; Salamida,
   F.; Salazar, H.; Salina, G.; Sánchez, F.; Santander, M.; Santos,
   E. M.; Sarkar, S.; Sato, R.; Scherini, V.; Schieler, H.; Schmidt,
   T.; Scholten, O.; Schovánek, P.; Schüssler, F.; Sciutto, S. J.;
   Scuderi, M.; Semikoz, D.; Sequeiros, G.; Shellard, R. C.; Siffert,
   B. B.; Sigl, G.; Skelton, P.; Slater, W.; de Grande, N. Smetniansky;
   Smiałkowski, A.; Šmída, R.; Smith, B. E.; Snow, G. R.; Sokolsky,
   P.; Sommers, P.; Sorokin, J.; Spinka, H.; Strazzeri, E.; Stutz, A.;
   Suarez, F.; Suomijärvi, T.; Supanitsky, A. D.; Swain, J.; Szadkowski,
   Z.; Tamashiro, A.; Tamburro, A.; Tascau, O.; Ticona, R.; Timmermans,
   C.; Tkaczyk, W.; Todero Peixoto, C. J.; Tonachini, A.; Torresi,
   D.; Travnicek, P.; Tripathi, A.; Tristram, G.; Tscherniakhovski,
   D.; Tueros, M.; Tunnicliffe, V.; Ulrich, R.; Unger, M.; Urban, M.;
   Valdés Galicia, J. F.; Valiño, I.; Valore, L.; van den Berg, A. M.;
   van Elewyck, V.; Vazquez, R. A.; Veberič, D.; Veiga, A.; Velarde,
   A.; Venters, T.; Verzi, V.; Videla, M.; Villaseñor, L.; Vo van, T.;
   Vorobiov, S.; Voyvodic, L.; Wahlberg, H.; Wainberg, O.; Waldenmaier,
   T.; Walker, P.; Warner, D.; Watson, A. A.; Westerhoff, S.; Wiebusch,
   C.; Wieczorek, G.; Wiencke, L.; Wilczyńska, B.; Wilczyński, H.;
   Wileman, C.; Winnick, M. G.; Xu, J.; Yamamoto, T.; Younk, P.; Zas,
   E.; Zavrtanik, D.; Zavrtanik, M.; Zech, A.; Zepeda, A.; Zha, M.;
   Ziolkowski, M.; Pierre Auger Collaboration
Bibcode: 2007APh....27..244A
Altcode: 2006astro.ph..7382T
  Data from the Pierre Auger Observatory are analyzed to search
  for anisotropies near the direction of the Galactic Centre at EeV
  energies. The exposure of the surface array in this part of the
  sky is already significantly larger than that of the fore-runner
  experiments. Our results do not support previous findings of localized
  excesses in the AGASA and SUGAR data. We set an upper bound on a
  point-like flux of cosmic rays arriving from the Galactic Centre
  which excludes several scenarios predicting sources of EeV neutrons
  from Sagittarius A. Also the events detected simultaneously by the
  surface and fluorescence detectors (the ‘hybrid’ data set), which
  have better pointing accuracy but are less numerous than those of the
  surface array alone, do not show any significant localized excess from
  this direction.

Title: The geometry of <ASTROBJ>PSR B0031-07</ASTROBJ>
Authors: Smits, J. M.; Mitra, D.; Stappers, B. W.; Kuijpers, J.;
   Weltevrede, P.; Jessner, A.; Gupta, Y.
Bibcode: 2007A&A...465..575S
Altcode: 2007astro.ph..1893S
  Context: <ASTROBJ>PSR B0031-07</ASTROBJ> is well known to exhibit
  three different modes of drifting sub-pulses (mode A, B and C). It
  has recently been shown that in a multifrequency observation,
  consisting of 2700 pulses, all driftmodes were visible at low
  frequencies, while at 4.85 GHz only mode-A drift or non-drifting
  emission was detected. This suggests that modes A and B are emitted
  in sub-beams, rotating at a fixed distance from the magnetic axis,
  with the mode-B sub-beams being closer to the magnetic axis than the
  mode-A sub-beams. Diffuse emission between the sub-beams can account
  for the non-drifting emission. <BR />Aims: Using the results of an
  analysis of simultaneous multifrequency observations of <ASTROBJ>PSR
  B0031-07</ASTROBJ>, we set out to construct a geometrical model that
  includes emission from both sub-beams and diffuse emission and describes
  the regions of the radio emission of <ASTROBJ>PSR B0031-07</ASTROBJ>
  at each emission frequency for driftmodes A and B. <BR />Methods:
  Based on the vertical spacing between driftbands, we have determined
  the driftmode of each sequence of drift. To restrict the model, we
  calculated average polarisation and intensity characteristics for each
  driftmode and at each frequency. <BR />Results: The model reproduces the
  observed polarisation and intensity characteristics, suggesting that
  diffuse emission plays an important role in the emission properties
  of <ASTROBJ>PSR B0031-07</ASTROBJ>. The model further suggests that
  the emission heights of this pulsar range from a few kilometers to a
  little over 10 kilometers above the pulsar surface. We also find that
  the relationships between height and frequency of emission that follow
  from curvature radiation and from plasma-frequency emission could not
  be used to reproduce the observed frequency dependence of the width
  of the average intensity profiles.

Title: An upper limit to the photon fraction in cosmic rays above
    10<SUP>19</SUP> eV from the Pierre Auger Observatory
Authors: Abraham, J.; Aglietta, M.; Aguirre, C.; Allard, D.; Allekotte,
   I.; Allison, P.; Alvarez, C.; Alvarez-Muñiz, J.; Ambrosio, M.;
   Anchordoqui, L.; Anjos, J. C.; Aramo, C.; Arisaka, K.; Armengaud,
   E.; Arneodo, F.; Arqueros, F.; Asch, T.; Asorey, H.; Atulugama,
   B. S.; Aublin, J.; Ave, M.; Avila, G.; Bacelar, J.; Bäcker, T.;
   Badagnani, D.; Barbosa, A. F.; Barbosa, H. M. J.; Barkhausen, M.;
   Barnhill, D.; Barroso, S. L. C.; Bauleo, P.; Beatty, J.; Beau, T.;
   Becker, B. R.; Becker, K. H.; Bellido, J. A.; Benzvi, S.; Berat,
   C.; Bergmann, T.; Bernardini, P.; Bertou, X.; Biermann, P. L.;
   Billoir, P.; Blanch-Bigas, O.; Blanco, F.; Blasi, P.; Bleve, C.;
   Blümer, H.; Boghrat, P.; Boháčová, M.; Bonifazi, C.; Bonino,
   R.; Boratav, M.; Brack, J.; Brunet, J. M.; Buchholz, P.; Busca,
   N. G.; Caballero-Mora, K. S.; Cai, B.; Camin, D. V.; Capdevielle,
   J. N.; Caruso, R.; Castellina, A.; Cataldi, G.; Cazón, L.; Cester,
   R.; Chauvin, J.; Chiavassa, A.; Chinellato, J. A.; Chou, A.; Chye,
   J.; Claes, D.; Clark, P. D. J.; Clay, R. W.; Clay, S. B.; Connolly,
   B.; Cordier, A.; Cotti, U.; Coutu, S.; Covault, C. E.; Cronin, J.;
   Dagoret-Campagne, S.; Dang Quang, T.; Darriulat, P.; Daumiller, K.;
   Dawson, B. R.; de Almeida, R. M.; de Carvalho, L. A.; de Donato, C.;
   de Jong, S. J.; de Mello, W. J. M.; de Mello Neto, J. R. T.; de Mitri,
   I.; de Oliveira, M. A. L.; de Souza, V.; Del Peral, L.; Deligny, O.;
   Della Selva, A.; Delle Fratte, C.; Dembinski, H.; di Giulio, C.; Diaz,
   J. C.; Dobrigkeit, C.; D'Olivo, J. C.; Dornic, D.; Dorofeev, A.; Dova,
   M. T.; D'Urso, D.; Duvernois, M. A.; Engel, R.; Epele, L.; Erdmann,
   M.; Escobar, C. O.; Etchegoyen, A.; Ewers, A.; Facal San Luis, P.;
   Falcke, H.; Fauth, A. C.; Fazio, D.; Fazzini, N.; Fernández, A.;
   Ferrer, F.; Ferry, S.; Fick, B.; Filevich, A.; Filipčič, A.; Fleck,
   I.; Fokitis, E.; Fonte, R.; Fuhrmann, D.; Fulgione, W.; García, B.;
   Garcia-Pinto, D.; Garrard, L.; Garrido, X.; Geenen, H.; Gelmini, G.;
   Gemmeke, H.; Geranios, A.; Ghia, P. L.; Giller, M.; Gitto, J.; Glass,
   H.; Gobbi, F.; Gold, M. S.; Gomez Albarracin, F.; Gómez Berisso,
   M.; Gómez Herrero, R.; Gonçalves Do Amaral, M.; Gongora, J. P.;
   Gonzalez, D.; Gonzalez, J. G.; González, M.; Góra, D.; Gorgi,
   A.; Gouffon, P.; Grassi, V.; Grillo, A.; Grunfeld, C.; Grupen, C.;
   Guarino, F.; Guedes, G. P.; Gutiérrez, J.; Hague, J. D.; Hamilton,
   J. C.; Harakeh, M. N.; Harari, D.; Harmsma, S.; Hartmann, S.; Harton,
   J. L.; Healy, M. D.; Hebbeker, T.; Heck, D.; Hojvat, C.; Homola, P.;
   Hörandel, J.; Horneffer, A.; Horvat, M.; Hrabovský, M.; Iarlori, M.;
   Insolia, A.; Kaducak, M.; Kalashev, O.; Kampert, K. H.; Keilhauer,
   B.; Kemp, E.; Klages, H. O.; Kleifges, M.; Kleinfeller, J.; Knapik,
   R.; Knapp, J.; Koang, D. -H.; Kolotaev, Y.; Kopmann, A.; Krömer,
   O.; Kuhlman, S.; Kuijpers, J.; Kunka, N.; Kusenko, A.; Lachaud, C.;
   Lago, B. L.; Lebrun, D.; Lebrun, P.; Lee, J.; Letessier-Selvon, A.;
   Leuthold, M.; Lhenry-Yvon, I.; Longo, G.; López, R.; Lopez Agüera,
   A.; Lucero, A.; Maldera, S.; Malek, M.; Maltezos, S.; Mancarella,
   G.; Manceñido, M. E.; Mandat, D.; Mantsch, P.; Mariazzi, A. G.;
   Maris, I. C.; Martello, D.; Martinez, N.; Martínez, J.; Martínez,
   O.; Mathes, H. J.; Matthews, J.; Matthews, J. A. J.; Matthiae, G.;
   Maurin, G.; Maurizio, D.; Mazur, P. O.; McCauley, T.; McEwen, M.;
   McNeil, R. R.; Medina, G.; Medina, M. C.; Medina Tanco, G.; Meli, A.;
   Melo, D.; Menichetti, E.; Menshikov, A.; Meurer, Chr.; Meyhandan, R.;
   Micheletti, M. I.; Miele, G.; Miller, W.; Mollerach, S.; Monasor, M.;
   Monnier Ragaigne, D.; Montanet, F.; Morales, B.; Morello, C.; Moreno,
   E.; Morris, C.; Mostafá, M.; Muller, M. A.; Mussa, R.; Navarra, G.;
   Nellen, L.; Newman-Holmes, C.; Newton, D.; Nguyen Thi, T.; Nichol,
   R.; Nierstenhöfer, N.; Nitz, D.; Nogima, H.; Nosek, D.; Nožka,
   L.; Oehlschläger, J.; Ohnuki, T.; Olinto, A.; Oliveira, L. F. A.;
   Olmos-Gilbaja, V. M.; Ortiz, M.; Ostapchenko, S.; Otero, L.; Palatka,
   M.; Pallotta, J.; Parente, G.; Parizot, E.; Parlati, S.; Patel, M.;
   Paul, T.; Payet, K.; Pech, M.; PeĶala, J.; Pelayo, R.; Pepe, I. M.;
   Perrone, L.; Petrera, S.; Petrinca, P.; Petrov, Y.; Pham Ngoc, D.;
   Pham Thi, T. N.; Piegaia, R.; Pierog, T.; Pisanti, O.; Porter, T. A.;
   Pouryamout, J.; Prado, L.; Privitera, P.; Prouza, M.; Quel, E. J.;
   Rautenberg, J.; Reis, H. C.; Reucroft, S.; Revenu, B.; Řídký, J.;
   Risi, A.; Risse, M.; Rivière, C.; Rizi, V.; Robbins, S.; Roberts, M.;
   Robledo, C.; Rodriguez, G.; Rodríguez Frías, D.; Rodriguez Martino,
   J.; Rodriguez Rojo, J.; Ros, G.; Rosado, J.; Roth, M.; Roucelle,
   C.; Rouillé-D'Orfeuil, B.; Roulet, E.; Rovero, A. C.; Salamida,
   F.; Salazar, H.; Salina, G.; Sánchez, F.; Santander, M.; Santos,
   E. M.; Sarkar, S.; Sato, R.; Scherini, V.; Schmidt, T.; Scholten, O.;
   Schovánek, P.; Schüssler, F.; Sciutto, S. J.; Scuderi, M.; Semikoz,
   D.; Sequeiros, G.; Shellard, R. C.; Siffert, B. B.; Sigl, G.; Skelton,
   P.; Slater, W.; Smetniansky de Grande, N.; Smiałkowski, A.; Šmída,
   R.; Smith, B. E.; Snow, G. R.; Sokolsky, P.; Sommers, P.; Sorokin,
   J.; Spinka, H.; Strazzeri, E.; Stutz, A.; Suarez, F.; Suomijärvi,
   T.; Supanitsky, A. D.; Swain, J.; Szadkowski, Z.; Tamashiro, A.;
   Tamburro, A.; Tascau, O.; Ticona, R.; Timmermans, C.; Tkaczyk,
   W.; Todero Peixoto, C. J.; Tonachini, A.; Torresi, D.; Travnicek,
   P.; Tripathi, A.; Tristram, G.; Tscherniakhovski, D.; Tueros, M.;
   Tunnicliffe, V.; Ulrich, R.; Unger, M.; Urban, M.; Valdés Galicia,
   J. F.; Valiño, I.; Valore, L.; van den Berg, A. M.; van Elewyck,
   V.; Vazquez, R. A.; Veberič, D.; Veiga, A.; Velarde, A.; Venters,
   T.; Verzi, V.; Videla, M.; Villaseñor, L.; Vo van, T.; Vorobiov, S.;
   Voyvodic, L.; Wahlberg, H.; Wainberg, O.; Waldenmaier, T.; Walker, P.;
   Warner, D.; Watson, A. A.; Westerhoff, S.; Wiebusch, C.; Wieczorek,
   G.; Wiencke, L.; Wilczyńska, B.; Wilczyński, H.; Wileman, C.;
   Winnick, M. G.; Xu, J.; Yamamoto, T.; Younk, P.; Zas, E.; Zavrtanik,
   D.; Zavrtanik, M.; Zech, A.; Zepeda, A.; Zha, M.; Ziolkowski, M.
Bibcode: 2007APh....27..155A
Altcode: 2006astro.ph..6619P
  An upper limit of 16% (at 95% c.l.) is derived for the photon fraction
  in cosmic rays with energies greater than 10<SUP>19</SUP> eV, based on
  observations of the depth of shower maximum performed with the hybrid
  detector of the Pierre Auger Observatory. This is the first such limit
  on photons obtained by observing the fluorescence light profile of air
  showers. This upper limit confirms and improves on previous results from
  the Haverah Park and AGASA surface arrays. Additional data recorded with
  the Auger surface detectors for a subset of the event sample support the
  conclusion that a photon origin of the observed events is not favored.

Title: Radio detection of cosmic ray air showers with LOPES
Authors: Huege, T.; Lopes Collaboration; Apel, W. D.; Asch, T.;
   Badea, A. F.; Bähren, L.; Bekk, K.; Bercuci, A.; Bertaina, M.;
   Biermann, P. L.; Blümer, J.; Bozdog, H.; Brancus, I. M.; Buitink,
   S.; Brüggemann, M.; Buchholz, P.; Butcher, H.; Chiavassa, A.;
   Cossavella, F.; Daumiller, K.; di Pierro, F.; Doll, P.; Engel, R.;
   Falcke, H.; Gemmeke, H.; Ghia, P. L.; Glasstetter, R.; Grupen, C.;
   Hakenjos, A.; Haungs, A.; Heck, D.; Hörandel, J. R.; Horneffer, A.;
   Isar, P. G.; Kampert, K. H.; Kolotaev, Y.; Krömer, O.; Kuijpers,
   J.; Lafebre, S.; Mathes, H. J.; Mayer, H. J.; Meurer, C.; Milke, J.;
   Mitrica, B.; Morello, C.; Navarra, G.; Nehls, S.; Nigl, A.; Obenland,
   R.; Oehlschläger, J.; Ostapchenko, S.; Over, S.; Petcu, M.; Petrovic,
   J.; Pierog, T.; Plewnia, S.; Rebel, H.; Risse, A.; Roth, M.; Schieler,
   H.; Sima, O.; Singh, K.; Stümpert, M.; Toma, G.; Trinchero, G. C.;
   Ulrich, H.; van Buren, J.; Walkowiak, W.; Weindl, A.; Wochele, J.;
   Zabierowski, J.; Zensus, J. A.; Zimmermann, D.
Bibcode: 2007NuPhS.165..341H
Altcode: 2006astro.ph..9427H; 2007NuPhS.165..341T
  In the last few years, radio detection of cosmic ray air showers has
  experienced a true renaissance, becoming manifest in a number of new
  experiments and simulation efforts. In particular, the LOPES project has
  successfully implemented modern interferometric methods to measure the
  radio emission from extensive air showers. LOPES has confirmed that
  the emission is coherent and of geomagnetic origin, as expected by
  the geosynchrotron mechanism, and has demonstrated that a large scale
  application of the radio technique has great potential to complement
  current measurements of ultra-high energy cosmic rays. We describe the
  current status, most recent results and open questions regarding radio
  detection of cosmic rays and give an overview of ongoing research and
  development for an application of the radio technique in the framework
  of the Pierre Auger Observatory.

Title: The geometry of PSR B0031-07
Authors: Smits, R.; Mitra, D.; Stappers, B.; Kuijpers, J.; Weltevrede,
   P.; Jessner, A.; Gupta, Y.
Bibcode: 2007whsn.conf..161S
Altcode: 2006astro.ph.12684S
  Here we present the results from an analysis of a multifrequency
  simultaneous observation of PSR B0031$-$07. We have constructed a
  geometrical model, based on an empirical relationship between height
  and frequency of emission, that reproduces many of the observed
  characteristics. The model suggests very low emission altitudes for
  this pulsar of only a few kilometers above the star's surface.

Title: Radio emission of highly inclined cosmic ray air showers
    measured with LOPES
Authors: Petrovic, J.; Apel, W. D.; Asch, T.; Badea, F.; Bähren, L.;
   Bekk, K.; Bercuci, A.; Bertaina, M.; Biermann, P. L.; Blümer, J.;
   Bozdog, H.; Brancus, I. M.; Brüggemann, M.; Buchholz, P.; Buitink,
   S.; Butcher, H.; Chiavassa, A.; Cossavella, F.; Daumiller, K.; di
   Pierro, F.; Doll, P.; Engel, R.; Falcke, H.; Gemmeke, H.; Ghia, P. L.;
   Glasstetter, R.; Grupen, C.; Haungs, A.; Heck, D.; Hörandel, J. R.;
   Horneffer, A.; Huege, T.; Kampert, K. -H.; Kolotaev, Y.; Krömer, O.;
   Kuijpers, J.; Lafebre, S.; Mathes, H. J.; Mayer, H. J.; Meurer, C.;
   Milke, J.; Mitrica, B.; Morello, C.; Navarra, G.; Nehls, S.; Nigl, A.;
   Obenland, R.; Oehlschläger, J.; Ostapchenko, S.; Over, S.; Petcu, M.;
   Pierog, T.; Plewnia, S.; Rebel, H.; Risse, A.; Roth, M.; Schieler,
   H.; Sima, O.; Singh, K.; Stümpert, M.; Toma, G.; Trinchero, G. C.;
   Ulrich, H.; van Buren, J.; Walkowiak, W.; Weindl, A.; Wochele, J.;
   Zabierowski, J.; Zensus, J. A.; Zimmermann, D.
Bibcode: 2007A&A...462..389P
Altcode: 2006astro.ph..4273P
  Aims:The capability of radio antenna arrays to measure cosmic ray
  air showers with very large zenith angles is explored. This is
  important, since a possible neutrino detection has to fulfill two
  requirements. First: antennas should be able to detect very inclined
  cosmic ray air showers, and second: it should be possible to estimate
  the distance to the shower maximum, since neutrinos are most likely
  to travel far through the Earth's atmosphere without interaction
  and induce air showers close to the ground. <BR />Methods: LOPES
  (LOFAR PrototypE Station; LOFAR - LOw Frequency ARray), an array
  of dipole antennas, is used for the detection of inclined cosmic
  ray air showers. LOPES is co-located and triggered by the KASCADE
  (KArlsruhe Shower Core and Array DEtector) experiment, which also
  provides information on air shower properties such as electron and
  muon numbers on the ground, as well as the arrival direction. Radio
  emission of nearly vertical cosmic ray air showers has been detected
  by LOPES. <BR />Results: LOPES-10 (the first phase of LOPES, consisting
  of 10 antennas) detected a significant number of cosmic ray air showers
  with a zenith angle larger than 50°, and many of these have very high
  radio field strengths. The most inclined event that has been detected
  with LOPES-10 has a zenith angle of almost 80°. This is proof that
  the new technique is also applicable for cosmic ray air showers with
  high inclinations, which in the case that they are initiated close to
  the ground, can be a signature of neutrino events. <BR />Conclusions:
  .Our results indicate that arrays of simple radio antennas can be
  used for the detection of highly inclined air showers, which might be
  triggered by neutrinos. In addition, we found that the radio pulse
  height (normalized with the muon number) for highly inclined events
  increases with the geomagnetic angle, which confirms the geomagnetic
  origin of radio emission in cosmic ray air showers.

Title: Frequency Dependence of the Drifting Sub-Pulses of PSR
    B 0031-07
Authors: Smits, J. M.; Mitra, D.; Kuijpers, J.
Bibcode: 2006ChJAS...6b..24S
Altcode:
  The well known drifter PSR B0031-07 is known to exhibit drifting
  sub-pulses where the spacing between the drift bands (P_3) shows
  three distinct modes A, B and C corresponding to 13, 7 and 4 times
  the pulsar period, respectively. We have investigated periodicities
  and polarisation properties of PSR B0031-07 for a sequence of 2700
  single pulses taken simultaneously at 328 MHz and 4.85 GHz. We found
  that mode A occurs simultaneously at these frequencies, while modes B
  and C only occur at 328 MHz. However, when the pulsar is emitting in
  mode B at the lower frequency there is still emission at the higher
  frequency, hinting towards the presence of mode B emission at a weaker
  level. Further, we have established that modes A and B are associated
  with two orthogonal modes of polarisation, respectively. Based on
  these observations, we suggest a geometrical model where modes A and
  B at a given frequency are emitted in two concentric rings around the
  magnetic axis with mode B being nested inside mode A.

Title: Progress in air shower radio measurements: Detection of
    distant events
Authors: LOPES Collaboration; Apel, W. D.; Asch, T.; Badea, A. F.;
   Bähren, L.; Bekk, K.; Bercuci, A.; Bertaina, M.; Biermann, P. L.;
   Blümer, J.; Bozdog, H.; Brancus, I. M.; Buitink, S.; Brüggemann, M.;
   Buchholz, P.; Butcher, H.; Chiavassa, A.; Cossavella, F.; Daumiller,
   K.; di Pierro, F.; Doll, P.; Engel, R.; Falcke, H.; Gemmeke, H.; Ghia,
   P. L.; Glasstetter, R.; Grupen, C.; Haungs, A.; Heck, D.; Hörandel,
   J. R.; Horneffer, A.; Huege, T.; Kampert, K. H.; Kolotaev, Y.; Krömer,
   O.; Kuijpers, J.; Lafebre, S.; Mathes, H. J.; Mayer, H. J.; Meurer,
   C.; Milke, J.; Mitrica, B.; Morello, C.; Navarra, G.; Nehls, S.;
   Nigl, A.; Obenland, R.; Oehlschläger, J.; Ostapchenko, S.; Over, S.;
   Petcu, M.; Petrovic, J.; Pierog, T.; Plewnia, S.; Rebel, H.; Risse, A.;
   Roth, M.; Schieler, H.; Sima, O.; Singh, K.; Stümpert, M.; Toma, G.;
   Trinchero, G. C.; Ulrich, H.; van Buren, J.; Walkowiak, W.; Weindl,
   A.; Wochele, J.; Zabierowski, J.; Zensus, J. A.; Zimmermann, D.
Bibcode: 2006APh....26..332L
Altcode: 2006astro.ph..7495A; 2006APh....26..332A
  Data taken during half a year of operation of 10 LOPES antennas
  (LOPES-10), triggered by EAS observed with KASCADE-Grande have been
  analysed. We report about the analysis of correlations of radio signals
  measured by LOPES-10 with extensive air shower events reconstructed
  by KASCADE-Grande, including shower cores at large distances. The
  efficiency of detecting radio signals induced by air showers up to
  distances of 700 m from the shower axis has been investigated. The
  results are discussed with special emphasis on the effects of the
  reconstruction accuracy for shower core and arrival direction on the
  coherence of the measured radio signal. In addition, the correlations
  of the radio pulse amplitude with the primary cosmic ray energy and
  with the lateral distance from the shower core are studied.

Title: LOFAR - Opening up a new window on the Universe
Authors: Rottgering, H. J. A.; Braun, R.; Barthel, P. D.; van Haarlem,
   M. P.; Miley, G. K.; Morganti, R.; Snellen, I.; Falcke, H.; de Bruyn,
   A. G.; Stappers, R. B.; Boland, W. H. W. M.; Butcher, H. R.; de Geus,
   E. J.; Koopmans, L.; Fender, R.; Kuijpers, J.; Schilizzi, R. T.;
   Vogt, C.; Wijers, R. A. M. J.; Wise, M.; Brouw, W. N.; Hamaker,
   J. P.; Noordam, J. E.; Oosterloo, T.; Bahren, L.; Brentjens, M. A.;
   Wijnholds, S. J.; Bregman, J. D.; van Cappellen, W. A.; Gunst, A. W.;
   Kant, G. W.; Reitsma, J.; van der Schaaf, K.; de Vos, C. M.
Bibcode: 2006astro.ph.10596R
Altcode:
  LOFAR, the Low Frequency Array, is a next-generation radio telescope
  that is being built in Northern Europe and expected to be fully
  operational at the end of this decade. It will operate at frequencies
  from 15 to 240 MHz (corresponding to wavelengths of 20 to 1.2 m). Its
  superb sensitivity, high angular resolution, large field of view
  and flexible spectroscopic capabilities will represent a dramatic
  improvement over previous facilities at these wavelengths. As such,
  LOFAR will carry out a broad range of fundamental astrophysical
  studies. The design of LOFAR has been driven by four fundamental
  astrophysical applications: (i) The Epoch of Reionisation, (ii)
  Extragalactic Surveys and their exploitation to study the formation and
  evolution of clusters, galaxies and black holes, (iii) Transient Sources
  and their association with high energy objects such as gamma ray bursts,
  and (iv) Cosmic Ray showers and their exploitation to study the origin
  of ultra-high energy cosmic rays. In this conference the foreseen LOFAR
  work on the epoch of reionisation has been covered by de Bruyn and on
  cosmic ray showers by Falcke. During this contribution we will first
  present the LOFAR project with an emphasis on the challenges faced when
  carrying out sensitive imaging at low radio frequencies. Subsequently,
  we will discuss LOFAR's capabilities to survey the low-frequency
  radio sky. Main aims for the planned surveys are studies of z&gt;6
  radio galaxies, diffuse emission associated with distant clusters and
  starbursting galaxies at z&gt;2.

Title: The solar flare of the 14th of July 2000 (L3+C detector
    results)
Authors: Achard, P.; Adrian, O.; Aguilar-Benitez, M.; van den Akker,
   M.; Alcaraz, J.; Alemanni, G.; Allaby, J.; Aloisio, A.; Alviggi, M. G.;
   Anderhub, H.; Andreev, V. P.; Anselmo, F.; Arefiev, A.; Azemoon, T.;
   Aziz, T.; Bagnaia, P.; Bajo, A.; Baksay, G.; Baksay, L.; Bähr, J.;
   Baldew, S. V.; Banerjee, S.; Banerjee, Sw.; Barczyk, A.; Barillère,
   R.; Bartalini, P.; Basile, M.; Batalova, N.; Battiston, R.; Bay, A.;
   Becattini, F.; Becker, U.; Behner, F.; Bellucci, L.; Berbeco, R.;
   Berdugo, J.; Berges, P.; Bertucci, B.; Betev, B. L.; Biasini, M.;
   Biglietti, M.; Biland, A.; Blaising, J. J.; Blyth, S. C.; Bobbink,
   G. J.; Böhm, A.; Boldizsar, L.; Borgia, B.; Bottai, S.; Bourilkov,
   D.; Bourquin, M.; Braccini, S.; Branson, J. G.; Brochu, F.; Burger,
   J. D.; Burger, W. J.; Cai, X. D.; Capell, M.; Cara Romeo, G.; Carlino,
   G.; Cartacci, A.; Casaus, J.; Cavallari, F.; Cavallo, N.; Cecchi, C.;
   Cerrada, M.; Chamizo, M.; Chiarusi, T.; Chang, Y. H.; Chemarin, M.;
   Chen, A.; Chen, G.; Chen, G. M.; Chen, H. F.; Chen, H. S.; Chiefari,
   G.; Cifarelli, L.; Cindolo, F.; Clare, I.; Clare, R.; Coignet, G.;
   Colino, N.; Costantini, S.; de la Cruz, B.; Cucciarelli, S.; de
   Asmundis, R.; Déglon, P.; Debreczeni, J.; Degré, A.; Dehmelt, K.;
   Deiters, K.; della Volpe, D.; Delmeire, E.; Denes, P.; DeNotaristefani,
   F.; De Salvo, A.; Diemoz, M.; Dierckxsens, M.; Ding, L. K.; Dionisi,
   C.; Dittmar, M.; Doria, A.; Dova, M. T.; Duchesneau, D.; Duda, M.;
   Duran, I.; Echenard, B.; Eline, A.; El Hage, A.; El Mamouni, H.;
   Engler, A.; Eppling, F. J.; Extermann, P.; Faber, G.; Falagan, M. A.;
   Falciano, S.; Favara, A.; Fay, J.; Fedin, O.; Felcini, M.; Ferguson,
   T.; Fesefeldt, H; Fiandrini, E.; Field, J. H.; Filthaut, F.; Fisher,
   W.; Forconi, G.; Freudenreich, K.; Furetta, C.; Galaktionov, Yu.;
   Ganguli, S. N.; Garcia-Abia, P.; Gataullin, M.; Gentile, S.; Giagu,
   S.; Gong, Z. F.; Grabosch, H. J.; Grenier, G.; Grimm, O.; Groenstege,
   H.; Gruenewald, M. W.; Guida, M.; Guo, Y. N.; Gupta, S. K.; Gupta,
   V. K.; Gurtu, A.; Gutay, L. J.; Haas, D.; Haller, Ch.; Hatzifotiadou,
   D.; Hayashi, Y.; He, Z. X.; Hebbeker, T.; Hervé, A.; Hirschfelder,
   J.; Hofer, H.; Hofer, H.; Hohlmann, M.; Holzner, A.; Hou, S. R.; Huo,
   A. X.; Ito, N.; Jin, B. N.; Jindal, P.; Jing, C. L.; Jones, L. W.;
   de Jong, P.; Josa-Mutuberría, I.; Kantserov, V.; Kaur, M.; Kawakami,
   S.; Kienzle-Focacci, M. N.; Kim, J. K.; Kirkby, J.; Kittel, W.;
   Klimentov, A.; König, A. C.; Kok, E.; Korn, A.; Kopal, M.; Koutsenko,
   V.; Kräber, M.; Kuang, H. H.; Kraemer, R. W.; Krüger, A.; Kuijpers,
   J.; Kunin, A.; Ladron de Guevara, P.; Laktineh, I.; Landi, G.; Lebeau,
   M.; Lebedev, A.; Lebrun, P.; Lecomte, P.; Lecoq, P.; Le Coultre,
   P.; Le Goff, J. M.; Lei, Y.; Leich, H.; Leiste, R.; Levtchenko, M.;
   Levtchenko, P.; Li, C.; Li, L.; Li, Z. C.; Likhoded, S.; Lin, C. H.;
   Lin, W. T.; Linde, F. L.; Lista, L.; Liu, Z. A.; Lohmann, W.; Longo,
   E.; Lu, Y. S.; Luci, C.; Luminari, L.; Lustermann, W.; Ma, W. G.;
   Ma, X. H.; Ma, Y. Q.; Malgeri, L.; Malinin, A.; Maña, C.; Mans, J.;
   Martin, J. P.; Marzano, F.; Mazumdar, K.; McNeil, R. R.; Meng, X. W.;
   Merola, L.; Meschini, M.; Metzger, W. J.; Mihul, A.; van Mil, A.;
   Milcent, H.; Mirabelli, G.; Mnich, J.; Mohanty, G. B.; Monteleoni,
   B.; Muanza, G. S.; Muijs, A. J. M.; Musy, M.; Nagy, S.; Nahnhauer,
   R.; Naumov, V. A.; Natale, S.; Napolitano, M.; Nessi-Tedaldi, F.;
   Newman, H.; Nisati, A.; Novak, T.; Nowak, H.; Ofierzynski, R.;
   Organtini, G.; Pal, I.; Palomares, C.; Paolucci, P.; Paramatti, R.;
   Parriaud, J. -F.; Passaleva, G.; Patricelli, S.; Paul, T.; Pauluzzi,
   M.; Paus, C.; Pauss, F.; Pedace, M.; Pensotti, S.; Perret-Gallix,
   D.; Petersen, B.; Piccolo, D.; Pierella, F.; Pieri, M.; Pioppi, M.;
   Piroué, P. A.; Pistolesi, E.; Plyaskin, V.; Pohl, M.; Pojidaev, V.;
   Pothier, J.; Prokofiev, D.; Qing, C. R.; Rahal-Callot, G.; Rahaman,
   M. A.; Raics, P.; Raja, N.; Ramelli, R.; Rancoita, P. G.; Ranieri,
   R.; Raspereza, A.; Ravindran, K. C.; Razis, P.; Rembeczki, S.; Ren,
   D.; Rescigno, M.; Reucroft, S.; Rewiersma, P.; Riemann, S.; Rojkov,
   A.; Romero, L.; Rosca, A.; Rosemann, C.; Rosenbleck, C.; Rosier-Lees,
   S.; Roth, S.; Rubio, J. A.; Ruggiero, G.; Rykaczewski, H.; Sakharov,
   A.; Saremi, S.; Sarkar, S.; Salicio, J.; Sanchez, E.; Schäfer,
   C.; Schegelsky, V.; Schoeneich, B.; Schotanus, D. J.; Sciacca, C.;
   Servoli, L.; Shen, C. Q.; Shevchenko, S.; Shivarov, N.; Shoutko,
   V.; Shumilov, E.; Shvorob, A.; Son, D.; Souga, C.; Spillantini, P.;
   Steuer, M.; Stickland, D. P.; Stoyanov, B.; Straessner, A.; Sudhakar,
   K.; Sultanov, G.; Sun, L. Z.; Sushkov, S.; Suter, H.; Swain, J. D.;
   Szillasi, Z.; Tang, X. W.; Tarjan, P.; Tauscher, L.; Taylor, L.;
   Tellili, B.; Teyssier, D.; Timmermans, C.; Ting, Samuel C. C.; Ting,
   S. M.; Tonwar, S. C.; Tóth, J.; Trowitzsch, G.; Tully, C.; Tung,
   K. L.; Ulbricht, J.; Unger, M.; Valente, E.; Verkooijen, H.; Van de
   Walle, R. T.; Vasquez, R.; Vesztergombi, G.; Vetlitsky, I.; Viertel,
   G.; Vivargent, M.; Vlachos, S.; Vodopianov, I.; Vogel, H.; Vogt,
   H.; Vorobiev, I.; Vorobyov, A. A.; Wadhwa, M.; Wang, R. G.; Wang,
   Q.; Wang, X. L.; Wang, X. W.; Wang, Z. M.; Weber, M.; van Wijk, R.;
   Wijnen, T. A. M.; Wilkens, H.; Wynhoff, S.; Xia, L.; Xu, Y. P.; Xu,
   Z. Z.; Yang, B. Z.; Yang, C. G.; Yang, H. J.; Yang, M.; Yang, X. F.;
   Yao, Z. G.; Yeh, S. C.; Yu, Z. Q.; Zalite, An.; Zalite, Yu.; Zhang,
   C.; Zhang, F.; Zhang, J.; Zhang, S.; Zhang, Z. P.; Zhao, J.; Zhou,
   S. J.; Zhu, G. Y.; Zhu, R. Y; Zhu, Q. Q.; Zhuang, H. L.; Zichichi,
   A.; Zimmermann, B.; Zöller, M.; Zwart, A. N. M.; L3 Collaboration
Bibcode: 2006A&A...456..351A
Altcode: 2006A&A...456..351L
  Aims.Several experiments have reported observations on possible
  correlations between the flux of high energy muons and intense solar
  flares. If confirmed, these observations would have significant
  implications for acceleration processes in the heliosphere able
  to accelerate protons and other ions to energies of at least
  tens of GeV. Methods: The solar flare of the 14 of July 2000
  offered a unique opportunity for the L3+C experiment to search for
  a correlated enhancement in the flux of muons using the L3 precision
  muon spectrometer. Its capabilities for observing a directional excess
  in the flux of muons above 15 GeV (corresponding to primary proton
  energies above 40 GeV) are presented along with observations made on
  the 14th of July 2000. Results: We report an excess which appeared at
  a time coincident with the peak increase of solar protons observed
  at lower energies. The probability that the excess is a background
  fluctuation is estimated to be 1%. No similar excess of the muon flux
  was observed up to 1.5 h after the solar flare time.

Title: A search for flaring very-high-energy cosmic γ-ray sources
    with the L3+C muon spectrometer
Authors: L3 Collaboration; Adriani, O.; Aguilar-Benitez, M.; van
   den Akker, M.; Alcaraz, J.; Alemanni, G.; Allaby, J.; Aloisio, A.;
   Alviggi, M. G.; Anderhub, H.; Andreev, V. P.; Anselmo, F.; Arefiev,
   A.; Azemoon, T.; Aziz, T.; Bagnaia, P.; Bajo, A.; Baksay, G.; Baksay,
   L.; Bähr, J.; Baldew, S. V.; Banerjee, S.; Banerjee, Sw.; Barczyk, A.;
   Barillère, R.; Bartalini, P.; Basile, M.; Batalova, N.; Battiston, R.;
   Bay, A.; Becattini, F.; Becker, U.; Behner, F.; Bellucci, L.; Berbeco,
   R.; Berdugo, J.; Berges, P.; Bertucci, B.; Betev, B. L.; Biasini, M.;
   Biglietti, M.; Biland, A.; Blaising, J. J.; Blyth, S. C.; Bobbink,
   G. J.; Böhm, A.; Boldizsar, L.; Borgia, B.; Bottai, S.; Bourilkov,
   D.; Bourquin, M.; Braccini, S.; Branson, J. G.; Brochu, F.; Burger,
   J. D.; Burger, W. J.; Cai, X. D.; Capell, M.; Cara Romeo, G.; Carlino,
   G.; Cartacci, A.; Casaus, J.; Cavallari, F.; Cavallo, N.; Cecchi, C.;
   Cerrada, M.; Chamizo, M.; Chang, Y. H.; Chemarin, M.; Chen, A.; Chen,
   G.; Chen, G. M.; Chen, H. F.; Chen, H. S.; Chiarusi, T.; Chiefari, G.;
   Cifarelli, L.; Cindolo, F.; Clare, I.; Clare, R.; Coignet, G.; Colino,
   N.; Costantini, S.; de La Cruz, B.; Cucciarelli, S.; de Asmundis,
   R.; Déglon, P.; Debreczeni, J.; Degré, A.; Dehmelt, K.; Deiters,
   K.; Della Volpe, D.; Delmeire, E.; Denes, P.; Denotaristefani, F.;
   de Salvo, A.; Diemoz, M.; Dierckxsens, M.; Ding, L. K.; Dionisi,
   C.; Dittmar, M.; Doria, A.; Dova, M. T.; Duchesneau, D.; Duda, M.;
   Duran, I.; Echenard, B.; Eline, A.; El Hage, A.; El Mamouni, H.;
   Engler, A.; Eppling, F. J.; Extermann, P.; Faber, G.; Falagan, M. A.;
   Falciano, S.; Favara, A.; Fay, J.; Fedin, O.; Felcini, M.; Ferguson,
   T.; Fesefeldt, H.; Fiandrini, E.; Field, J. H.; Filthaut, F.; Fisher,
   P. H.; Fisher, W.; Fisk, I.; Forconi, G.; Freudenreich, K.; Furetta,
   C.; Galaktionov, Yu.; Ganguli, S. N.; Garcia-Abia, P.; Gataullin, M.;
   Gentile, S.; Giagu, S.; Gong, Z. F.; Grabosch, H. J.; Grenier, G.;
   Grimm, O.; Groenstege, H.; Gruenewald, M. W.; Guida, M.; Guo, Y. N.;
   Gupta, S. K.; Gupta, V. K.; Gurtu, A.; Gutay, L. J.; Haas, D.; Haller,
   Ch.; Hatzifotiadou, D.; Hayashi, Y.; He, Z. X.; Hebbeker, T.; Hervé,
   A.; Hirschfelder, J.; Hofer, H.; Hofer, H.; Hohlmann, M.; Holzner, G.;
   Hou, S. R.; Huo, A. X.; Ito, N.; Jin, B. N.; Jindal, P.; Jing, C. L.;
   Jones, L. W.; de Jong, P.; Josa-Mutuberría, I.; Kantserov, V.; Kaur,
   M.; Kawakami, S.; Kienzle-Focacci, M. N.; Kim, J. K.; Kirkby, J.;
   Kittel, W.; Klimentov, A.; König, A. C.; Kok, E.; Korn, A.; Kopal,
   M.; Koutsenko, V.; Kräber, M.; Kuang, H. H.; Kraemer, R. W.; Krüger,
   A.; Kuijpers, J.; Kunin, A.; Ladron de Guevara, P.; Laktineh, I.;
   Landi, G.; Lebeau, M.; Lebedev, A.; Lebrun, P.; Lecomte, P.; Lecoq,
   P.; Le Coultre, P.; Le Goff, J. M.; Lei, Y.; Leich, H.; Leiste, R.;
   Levtchenko, M.; Levtchenko, P.; Li, C.; Li, L.; Li, Z. C.; Likhoded,
   S.; Lin, C. H.; Lin, W. T.; Linde, F. L.; Lista, L.; Liu, Z. A.;
   Lohmann, W.; Longo, E.; Lu, Y. S.; Luci, C.; Luminari, L.; Lustermann,
   W.; Ma, W. G.; Ma, X. H.; Ma, Y. Q.; Malgeri, L.; Malinin, A.; Maña,
   C.; Mans, J.; Martin, J. P.; Marzano, F.; Mazumdar, K.; McNeil, R. R.;
   Mele, S.; Meng, X. W.; Merola, L.; Meschini, M.; Metzger, W. J.; Mihul,
   A.; van Mil, A.; Milcent, H.; Mirabelli, G.; Mnich, J.; Mohanty, G. B.;
   Monteleoni, B.; Muanza, G. S.; Muijs, A. J. M.; Musicar, B.; Musy,
   M.; Nagy, S.; Nahnhauer, R.; Naumov, V. A.; Natale, S.; Napolitano,
   M.; Nessi-Tedaldi, F.; Newman, H.; Nisati, A.; Novak, T.; Nowak, H.;
   Ofierzynski, R.; Organtini, G.; Pal, I.; Palomares, C.; Paolucci,
   P.; Paramatti, R.; Parriaud, J. -F.; Passaleva, G.; Patricelli, S.;
   Paul, T.; Pauluzzi, M.; Paus, C.; Pauss, F.; Pedace, M.; Pensotti,
   S.; Perret-Gallix, D.; Petersen, B.; Piccolo, D.; Pierella, F.;
   Pieri, M.; Pioppi, M.; Piroué, P. A.; Pistolesi, E.; Plyaskin, V.;
   Pohl, M.; Pojidaev, V.; Pothier, J.; Prokofiev, D.; Quartieri, J.;
   Qing, C. R.; Rahal-Callot, G.; Rahaman, M. A.; Raics, P.; Raja, N.;
   Ramelli, R.; Rancoita, P. G.; Ranieri, R.; Raspereza, A.; Ravindran,
   K. C.; Razis, P.; Ren, D.; Rescigno, M.; Reucroft, S.; Rewiersma, P.;
   Riemann, S.; Riles, K.; Roe, B. P.; Rojkov, A.; Romero, L.; Rosca, A.;
   Rosemann, C.; Rosenbleck, C.; Rosier-Lees, S.; Roth, S.; Rubio, J. A.;
   Ruggiero, G.; Rykaczewski, H.; Saidi, R.; Sakharov, A.; Saremi, S.;
   Sarkar, S.; Salicio, J.; Sanchez, E.; Schäfer, C.; Schegelsky, V.;
   Schmitt, V.; Schoeneich, B.; Schopper, H.; Schotanus, D. J.; Sciacca,
   C.; Servoli, L.; Shen, C. Q.; Shevchenko, S.; Shivarov, N.; Shoutko,
   V.; Shumilov, E.; Shvorob, A.; Son, D.; Souga, C.; Spillantini, P.;
   Steuer, M.; Stickland, D. P.; Stoyanov, B.; Straessner, A.; Sudhakar,
   K.; Sulanke, H.; Sultanov, G.; Sun, L. Z.; Sushkov, S.; Suter, H.;
   Swain, J. D.; Szillasi, Z.; Tang, X. W.; Tarjan, P.; Tauscher, L.;
   Taylor, L.; Tellili, B.; Teyssier, D.; Timmermans, C.; Ting, Samuel
   C. C.; Ting, S. M.; Tonwar, S. C.; Tóth, J.; Trowitzsch, G.; Tully,
   C.; Tung, K. L.; Ulbricht, J.; Unger, M.; Valente, E.; Verkooijen,
   H.; van de Walle, R. T.; Vasquez, R.; Veszpremi, V.; Vesztergombi,
   G.; Vetlitsky, I.; Vicinanza, D.; Viertel, G.; Villa, S.; Vivargent,
   M.; Vlachos, S.; Vodopianov, I.; Vogel, H.; Vogt, H.; Vorobiev, I.;
   Vorobyov, A. A.; Wadhwa, M.; Wang, R. G.; Wang, Q.; Wang, X. L.;
   Wang, X. W.; Wang, Z. M.; Weber, M.; van Wijk, R.; Wijnen, T. A. M.;
   Wilkens, H.; Wynhoff, S.; Xia, L.; Xu, Y. P.; Xu, J. S.; Xu, Z. Z.;
   Yang, B. Z.; Yang, C. G.; Yang, H. J.; Yang, M.; Yang, X. F.; Yao,
   Z. G.; Yeh, S. C.; Yu, Z. Q.; Zalite, An.; Zalite, Yu.; Zhang, C.;
   Zhang, F.; Zhang, J.; Zhang, S.; Zhang, Z. P.; Zhao, J.; Zhou, S. J.;
   Zhu, G. Y.; Zhu, R. Y.; Zhu, Q. Q.; Zhuang, H. L.; Zichichi, A.;
   Zimmermann, B.; Zöller, M.; Zwart, A. N. M.
Bibcode: 2006APh....25..298A
Altcode: 2006APh....25..298L; 2006APh....25..298T
  The L3+C muon detector at the CERN electron positron collider, LEP,
  is used for the detection of very-high-energy cosmic γ-ray sources
  through the observation of muons of energies above 20, 30, 50 and
  100 GeV. Daily or monthly excesses in the rate of single-muon events
  pointing to some particular direction in the sky are searched for. The
  periods from mid July to November 1999, and April to November 2000 are
  considered. Special attention is also given to a selection of known
  γ-ray sources. No statistically significant excess is observed for
  any direction or any particular source.

Title: Scattering of magnetosonic waves in a relativistic and
    anisotropic magnetized plasma
Authors: Moortgat, Joachim; Kuijpers, Jan
Bibcode: 2006MNRAS.368.1110M
Altcode: 2006astro.ph..2314M
  Gravitational waves (GW) propagating through a magnetized plasma
  excite low-frequency magnetohydrodynamic (MHD) waves. In this paper, we
  investigate whether these waves can produce observable radio emission
  at higher frequencies by scattering on an anisotropic intrinsically
  relativistic distribution of electrons and positrons in the force-free
  wind surrounding a double neutron star binary merger. The relativistic
  particle distribution is assumed to be strictly along the magnetic field
  lines, while the magneto-plasma streams out at a relativistic speed from
  the neutron stars. In the case of Compton scattering of an incident MHD
  wave transverse to the magnetic field, we find that the probability
  of scattering to both a transverse x-mode and a quasi-longitudinal
  Langmuir-ordinary mode is suppressed when the frequency of the incident
  wave is below the local relativistic gyro-frequency, that is, when
  the magnetic field is very strong.

Title: Radio emission of highly inclined cosmic ray air showers
    measured with LOPES - possibility for neutrino detection
Authors: Petrovic, J.; Apel, W. D.; Badea, F.; Bähren, L.; Bekk, K.;
   Bercuci, A.; Bertaina, M.; Biermann, P. L.; Blümer, J.; Bozdog, H.;
   Brancus, I. M.; Buitink, S.; Brüggemann, M.; Buchholz, P.; Butcher,
   H.; Chiavassa, A.; Daumiller, K.; de Bruyn, A. G.; de Vos, C. M.;
   Di Pierro, F.; Doll, P.; Engel, R.; Falcke, H.; Gemmeke, H.; Ghia,
   P. L.; Glasstetter, R.; Grupen, C.; Haungs, A.; Heck, D.; Hörandel,
   J. R.; Horneffer, A.; Huege, T.; Kampert, K. -H.; Kant, G. W.; Klein,
   U.; Kolotaev, Y.; Koopman, Y.; Krömer, O.; Kuijpers, J.; Lafebre,
   S.; Maier, G.; Mathes, H. J.; Mayer, H. J.; Milke, J.; Mitrica,
   B.; Morello, C.; Navarra, G.; Nehls, S.; Nigl, A.; Obenland, R.;
   Oehlschläger, J.; Ostapchenko, S.; Over, S.; Pepping, H. J.; Petcu,
   M.; Pierog, T.; Plewnia, S.; Rebel, H.; Risse, A.; Roth, M.; Schieler,
   H.; Schoonderbeek, G.; Sima, O.; Mstümpert; Toma, G.; Trinchero,
   G. C.; Ulrich, H.; Valchierotti, S.; van Buren, J.; van Capellen, W.;
   Walkowiak, W.; Weindl, A.; Wijnholds, S.; Wochele, J.; Zabierowski,
   J.; Zensus, J. A.; Zimmermann, D.
Bibcode: 2006JPhCS..39..471P
Altcode: 2006astro.ph.11225J
  LOPES - LOFAR PrototypE Station (LOFAR - LOw Frequency ARray) is an
  array of dipole antennas used for the detection of radio emission
  from cosmic ray air showers. It is co-located and triggered by
  the KASCADE (KArlsruhe Shower Core and Array Detector) experiment,
  which also provides information about air shower properties like
  electron number N<SUB>e</SUB>, muon number N<SUB>µ</SUB>, azimuth
  and zenith angle. LOPES-10 (the first phase of LOPES, consisting of 10
  antennas) detected a significant number of cosmic ray air showers with
  a zenith angle larger than 50°, and many of those have very high field
  strengths. The most inclined event that has been detected with LOPES-10
  has a zenith angle of almost 80°. This is important, because cosmic
  ray air showers with large inclinations, triggered close to the ground,
  would be a signature of neutrino events. Due to the small baseline of
  the LOPES-10 detector, it is not yet possible to determine accuratelly
  the radius of curvature of the showers front, which is related to the
  distance to the maximum of shower development. However, this should be
  possible in the future with a large baseline radio telescope like LOFAR.

Title: Results from the KASCADE, KASCADE-Grande, and LOPES experiments
Authors: Hörandel, J. R.; Apel, W. D.; Badea, F.; Bähren, L.; Bekk,
   K.; Bercuci, A.; Bertaina, M.; Biermann, P. L.; Blümer, J.; Bozdog,
   H.; Brancus, I. M.; Brüggemann, M.; Buchholz, P.; Buitink, S.;
   Butcher, H.; Chiavassa, A.; Daumiller, K.; de Bruyn, A. G.; de Vos,
   C. M.; Di Pierro, F.; Doll, P.; Engel, R.; Engler, J.; Falcke, H.;
   Gemmeke, H.; Ghia, P. L.; Gils, H. -J.; Glasstetter, R.; Grupen, C.;
   Heck, D.; Haungs, A.; Horneffer, A.; Huege, T.; Kampert, K. -H.; Kant,
   G. W.; Klages, H. O.; Klein, U.; Kolotaev, Y.; Koopman, Y.; Krömer,
   O.; Kuijpers, J.; Lafebre, S.; Maier, G.; Mathes, H. J.; Mayer, H. J.;
   Milke, J.; Mitrica, B.; Morello, C.; Müller, M.; Navarra, G.; Nehls,
   S.; Nigl, A.; Obenland, R.; Oehlschläger, J.; Ostapchenko, S.; Over,
   S.; Pepping, H. J.; Petcu, M.; Petrovic, J.; Pierog, T.; Plewnia, S.;
   Rebel, H.; Risse, A.; Roth, M.; Schieler, H.; Schoonderbeek, G.; Sima,
   O.; Stümpert, M.; Toma, G.; Trinchero, G. C.; Ulrich, H.; van Buren,
   J.; van Capellen, W.; Wwalkowiak; Aweindl; Wijnholds, S.; Jwochele;
   Zabierowski, J.; Zensus, J. A.; Zimmermann, D.
Bibcode: 2006JPhCS..39..463H
Altcode: 2005astro.ph.11649H
  The origin of high-energy cosmic rays in the energy range from
  10<SUP>14</SUP> to 10<SUP>18</SUP> eV is explored with the KASCADE
  and KASCADE-Grande experiments. Radio signals from air showers are
  measured with the LOPES experiment. An overview on results is given.

Title: High-Energy Cosmic Rays Investigated by Air-Shower Measurements
    with KASCADE, Kascade-Grande and Lopes
Authors: Haungs, A.; Apel, W. D.; Badea, F.; Bähren, L.; Bekk, K.;
   Bercuci, A.; Bertaina, M.; Biermann, P. L.; Blümer, J.; Bozdog, H.;
   Brancus, I. M.; Brüggemann, M.; Buchholz, P.; Buitink, S.; Butcher,
   H.; Chiavassa, A.; Daumiller, K.; de Bruyn, A. G.; de Vos, C. M.;
   di Pierro, F.; Doll, P.; Engel, R.; Engler, J.; Falcke, H.; Gemmeke,
   H.; Ghia, P. L.; Gils, H. -J.; Glasstetter, R.; Grupen, C.; Heck, D.;
   Hörandel, J. R.; Horneffer, A.; Huege, T.; Kampert, K. -H.; Kant,
   G. W.; Klages, H. O.; Klein, U.; Kolotaev, Y.; Koopman, Y.; Krömer,
   O.; Kuijpers, J.; Lafebre, S.; Maier, G.; Mathes, H. J.; Mayer, H. J.;
   Milke, J.; Mitrica, B.; Morello, C.; Müller, M.; Navarra, G.; Nehls,
   S.; Nigl, A.; Obenland, R.; Oehlschläger, J.; Ostapchenko, S.; Over,
   S.; Pepping, H. J.; Petcu, M.; Petrovic, J.; Pierog, T.; Plewnia,
   S.; Rebel, H.; Risse, A.; Roth, M.; Schieler, H.; Schoonderbeek, G.;
   Sima, O.; Stümpert, M.; Toma, G.; Trinchero, G. C.; Ulrich, H.; van
   Buren, J.; van Capellen, W.; Walkowiak, W.; Weindl, A.; Wijnholds,
   S.; Wochele, J.; Zabierowski, J.; Zensus, J. A.; Zimmermann, D.
Bibcode: 2006apsp.conf..229H
Altcode:
  Recent results from the multi-detector set-up KASCADE on measurements
  of cosmic rays in the energy range of the so called knee (at ≈ 3
  PeV) are presented. The multidimensional analysis of the air shower
  data indicates a distinct knee in the energy spectra of light primary
  cosmic rays and an increasing dominance of heavy ones towards higher
  energies. This provides, together with the results of large scale
  anisotropy studies, implications for discriminating astrophysical models
  of the origin of the knee. To improve the reconstruction quality and
  statistics at higher energies, where the knee of the heavy primaries
  is expected at around 100 PeV, KASCADE has recently been extended by
  a factor 10 in area to the new experiment KASCADE-Grande. LOPES is
  set up at the location of the KASCADE-Grande experiment and measures
  radio pulses from extensive air showers. LOPES is designed as digital
  radio interferometer using high bandwidths and fast data processing and
  profits from the reconstructed air shower observables of KASCADE-Grande.

Title: Frequency dependence of orthogonal polarisation modes in
    pulsars
Authors: Smits, J. M.; Stappers, B. W.; Edwards, R. T.; Kuijpers,
   J.; Ramachandran, R.
Bibcode: 2006A&A...448.1139S
Altcode: 2005astro.ph.12107S
  We have carried out a study of the orthogonal polarisation mode
  behaviour as afunction of frequency of 18pulsars, using average pulsar
  data from the European Pulsar Network(EPN). Assuming that the radiation
  consists of two100% polarised completely orthogonal superposed modes we
  separated these modes, resulting in average pulse profiles of each mode
  at multiple frequencies for each pulsar. Furthermore, we studied the
  frequency dependence of the relative intensity of these modes. We found
  in many pulsars that the average pulse profiles of the twomodes differ
  in their dependence on frequency. In particular, we found that pulse
  components that are dominated by onemode tend to increase in intensity
  with increasing frequency with respect to the rest of the profile.

Title: Radio pulsar drifting sub-pulses and diocotron instability
Authors: Fung, P. K.; Khechinashvili, D.; Kuijpers, J.
Bibcode: 2006A&A...445..779F
Altcode:
  The potential role of a diocotron instability in causing drifting
  sub-pulses in radio pulsar emission is investigated for aligned magnetic
  rotators. It is assumed that the out-flowing plasma above a pulsar
  polar cap consists of an initially axially symmetric, hollow beam of
  relativistic electron positron pair plasma which carries an electric
  charge as well as a current. The occurrence of instability depends on
  shear in the angular velocity distribution of the beam as a function
  of axial distance. Instability occurs under typical pulsar conditions
  at mode numbers ≤ 40. It destroys the symmetry of the equilibrium
  configuration and leads to a carousel of density columns which rotates
  at fixed angular pattern speed. The process is applied to two pulsars
  with observed carousels of drifting sub-pulses, and the diocotron
  instability at corresponding mode number and axial distance is used
  as a diagnostic for the charge and current density of the polar flow.

Title: Advanced Detection Methods of Radio Signals from Cosmic Rays
    for KASCADE Grande and Auger
Authors: Gemmeke, H.; Apel, W. D.; Badea, F. A.; Bähren, L.; Bekk, K.;
   Bercuci, A.; Bertaina, M.; Biermann, P. L.; Blümer, J.; Bozdog, H.;
   Brancus, I. M.; Brüggemann, M.; Buchholz, P.; Buitink, S.; Butcher,
   H.; Chiavassa, A.; Daumiller, K.; De Bruyn, A. G.; De Vos, C. M.; Di
   Pierro, F.; Doll, P.; Engel, R.; Falcke, H.; Ghia, P. L.; Glasstetter,
   R.; Grupen, C.; Haungs, A.; Heck, D.; Hörandel, J. R.; Horneffer,
   A.; Huege, T.; Kampert, K. -H.; Kant, G. W.; Klein, U.; Kolotaev,
   Y.; Koopman, Y.; Krömer, O.; Kuijpers, J.; Lafebre, S.; Maier, G.;
   Mathes, H. J.; Mayers, H. J.; Milke, J.; Mitrica, B.; Morello, C.;
   Navarra, G.; Nehls, S.; Nigl, A.; Obenland, R.; Oehlschläger, J.;
   Ostapchenko, S.; Over, S.; Pepping, H. J.; Petcu, M.; Petrovic, J.;
   Pierog, T.; Plewnia, S.; Rebel, H.; Risse, A.; Roth, M.; Schieler,
   H.; Schoonderbeek, G.; Sima, O.; Stümpert, M.; Toma, G.; Trinchero,
   G. C.; Ulrich, H.; Van Buren, J.; Van Capellen, W.; Walkowiak, W.;
   Weindl, A.; Wijnholds, S.; Wochele, J.; Zabierowski, J.; Zensus,
   J. A.; Zimmermann, D.
Bibcode: 2006aren.conf..242G
Altcode:
  The LOPES experiment (LOfar Prototype Station) has been built at the
  KASCADE-Grande experiment in order to test the LOFAR (LOw Frequency
  ARray) technology and demonstrate its capability for radio measurements
  in Extensive Air Showers (EAS). After the first positive results in
  the framework of the KASCADE-Grande experiment we developed the next
  generation of antennas, electronics, and trigger. The main new features
  are easy calibration of antennas with precise detection of polarization,
  and good capability of self-triggering. The results from this new design
  are under test in Karlsruhe. Furthermore the background situation was
  measured and analyzed.

Title: Absolute Calibration of the LOPES Antenna System
Authors: Nehls, S.; Apel, W. D.; Badea, F.; Bähren, L.; Bekk, K.;
   Bercuci, A.; Bertaina, M.; Biermann, P. L.; Blümer, J.; Bozdog, H.;
   Brancus, I. M.; Brüggemann, M.; Buchholz, P.; Buitink, S.; Butcher,
   H.; Chiavassa, A.; Daumiller, K.; De Bruyn, A. G.; De Vos, C. M.;
   Di Pierro, F.; Doll, P.; Engel, R.; Falcke, H.; Gemmeke, H.; Ghia,
   P. L.; Glasstetter, R.; Grupen, C.; Hakenjos, A.; Haungs, A.; Heck,
   D.; Hörandel, J. R.; Horneffer, A.; Huege, T.; Kampert, K. -H.; Kant,
   G. W.; Klein, U.; Kolotaev, Y.; Koopman, Y.; Krömer, O.; Kuijpers,
   J.; Lafebre, S.; Maier, G.; Mathes, H. J.; Mayer, H. J.; Milke,
   J.; Mitrica, B.; Morello, C.; Navarra, G.; Nigl, A.; Obenland, R.;
   Oehlschläger, J.; Ostapchenko, S.; OVer, S.; Pepping, H. J.; Petcu,
   M.; Petrovic, J.; Pierogs, T.; Plewnia, S.; Rebel, H.; Risse, A.; Roth,
   M.; Schieler, H.; Schoonderbeek, G.; Sima, O.; Stümpert, M.; Toma,
   G.; Trinchero, G. C.; Ulrich, H.; Van Buren, J.; Van Capellen, W.;
   Walkowiak, W.; Weindl, A.; Wijnholds, S.; Wochele, J.; Zabierowski,
   J.; Zensus, J. A.; ZImmermann, D.
Bibcode: 2006aren.conf..187N
Altcode:
  Radio emission in extensive air showers arises from an interaction
  with the geomagnetic field and is subject of theoretical studies. This
  radio emission has advantages for the detection of high energy cosmic
  rays compared to secondary particle or fluorescence measurement
  methods. Radio antennas like the LOPES30 antenna system are suited to
  investigate this emission process by detecting the radio pulses. The
  characteristic observable parameters like electric field strength and
  pulse length require a calibration which was done with a reference radio
  source resulting in an amplification factor representing the system
  behavior in the environment of the KASCADE-Grande experiment. Knowing
  the amplification factor and the gain of the LOPES antennas LOPES30
  is calibrated absolutely for systematic analyses of the radio emission.

Title: Combined Lopes and Kascade-Grande Data Analysis
Authors: Haungs, A.; Apel, W. D.; Badea, F.; Bähren, L.; Bekk, K.;
   Bercuci, A.; Bertaina, M.; Biermann, P. L.; Blümer, J.; Bozdog, H.;
   Brancus, I. M.; Brüggemann, M.; Buchholz, P.; Buitink, S.; Butcher,
   H.; Chiavassa, A.; Daumiller, K.; de Bruyn, A. G.; de Vos, C. M.; di
   Pierro, F.; Doll, P.; Engel, R.; Falcke, H.; Gemmeke, H.; Ghia, P. L.;
   Glasstetter, R.; Grupen, C.; Heck, D.; Hörandel, J. R.; Horneffer,
   A.; Huege, T.; Kampert, K. -H.; Kant, G. W.; Klein, U.; Kolotaev,
   Y.; Koopman, Y.; Krömer, O.; Kuijpers, J.; Lafebre, S.; Maier, G.;
   Mathes, H. J.; Mayer, H. J.; Milke, J.; Mitrica, B.; Morello, C.;
   Navarra, G.; Nehls, S.; Nigl, A.; Obenland, R.; Oehlschläger, J.;
   Ostapchenko, S.; Over, S.; Pepping, H. J.; Petcu, M.; Petrovic, J.;
   Pierog, T.; Plewnia, S.; Rebel, H.; Risse, A.; Roth, M.; Schieler,
   H.; Schoonderbeek, G.; Sima, O.; Stümpert, M.; Toma, G.; Trinchero,
   G. C.; Ulrich, H.; van Buren, J.; van Capellen, W.; Walkowiak, W.;
   Weindl, A.; Wijnholds, S.; Wochele, J.; Zabierowski, J.; Zensus,
   J. A.; Zimmermann, D.
Bibcode: 2006IJMPA..21S.182H
Altcode: 2005astro.ph.10352H
  First analyses of coincident data of the LOPES (LOfar PrototypE Station)
  radio antennas with the particle air shower experiment KASCADE-Grande
  show basic correlations in the observed shower parameters, like the
  strength of the radio signal and the particle number, or comparing
  the estimated shower directions. In addition, an improvement of the
  experimental resolution of the shower parameters reconstructed by
  KASCADE-Grande can be obtained by including the data of the radio
  antennas. This important feature will be shown in this article
  explicitely by an example event.

Title: Jupiter Burst Observation with LOFAR/ITS
Authors: Nigl, A.; Kuijpers, J.; Falcke, H.; Zarka, P.; Bähren, L.
Bibcode: 2006pre6.conf..517N
Altcode: 2006pre4.conf..517N
  Io-induced Jupiter emission lies mainly in the frequency range from
  about 2 to 40 MHz [Zarka et al., 2001], which happens to coincide
  with the frequency band of the Low-Frequency Radio Array Initial Test
  Station (LOFAR/ITS). ITS is capable of measuring the radio signal with
  high time and frequency resolution, which makes it well-suited for
  the study of Jovian decametric emission (DAM). We present the first
  simultaneous Io-DAM observations of Jupiter at about 700 km distance
  between two instruments, LOFAR/ITS and the Nancay Decametric Array
  (NDA). We have detected emission from Jupiter during snapshots of a
  few seconds and identified detailed features in dynamic spectra taken
  with both instruments. This will be the basis for VLBI-like correlation
  of both waveforms. This article presents first and preliminary Jupiter
  observations with ITS. We analyze Faraday rotation, which is measured
  with linearly polarized antennas. We observe frequency modulation over
  a broad spectral range and demonstrate that the effect comes mainly
  from the Earth's ionosphere. This article presents first observations
  and discusses frequency modulated Faraday rotation.

Title: Absolute Calibration of the Lopes Antenna System
Authors: Nehls, S.; Apel, W. D.; Badea, F.; Bähren, L.; Bekk, K.;
   Bercuci, A.; Bertaina, M.; Biermann, P. L.; Blümer, J.; Bozdog, H.;
   Brancus, I. M.; Brüggemann, M.; Buchholz, P.; Buitink, S.; Butcher,
   H.; Chiavassa, A.; Daumiller, K.; de Bruyn, A. G.; de Vos, C. M.;
   di Pierro, F.; Doll, P.; Engel, R.; Falcke, H.; Gemmeke, H.; Ghia,
   P. L.; Glasstetter, R.; Grupen, C.; Hakenjos, A.; Haungs, A.; Heck,
   D.; Hörandel, J. R.; Horneffer, A.; Huege, T.; Kampert, K. -H.; Kant,
   G. W.; Klein, U.; Kolotaev, Y.; Koopman, Y.; Krömer, O.; Kuijpers,
   J.; Lafebre, S.; Maier, G.; Mathes, H. J.; Mayer, H. J.; Milke,
   J.; Mitrica, B.; Morello, C.; Navarra, G.; Nigl, A.; Obenland, R.;
   Oehlschläger, J.; Ostapchenko, S.; Over, S.; Pepping, H. J.; Petcu,
   M.; Petrovic, J.; Pierog, T.; Plewnia, S.; Rebel, H.; Risse, A.; Roth,
   M.; Schieler, H.; Schoonderbeek, G.; Sima, O.; Stümpert, M.; Toma,
   G.; Trinchero, G. C.; Ulrich, H.; van Buren, J.; van Capellen, W.;
   Walkowiak, W.; Weindl, A.; Wijnholds, S.; Wochele, J.; Zabierowski,
   J.; Zensus, J. A.; Zimmermann, D.
Bibcode: 2006IJMPA..21S.187N
Altcode: 2005astro.ph.10353N
  Radio emission in extensive air showers arises from an interaction
  with the geomagnetic field and is subject of theoretical studies. This
  radio emission has advantages for the detection of high energy cosmic
  rays compared to secondary particle or fluorescence measurement
  methods. Radio antennas like the LOPES30 antenna system are suited to
  investigate this emission process by detecting the radio pulses. The
  characteristic observable parameters like electric field strength and
  pulse length require a calibration which was done with a reference radio
  source resulting in an amplification factor representing the system
  behavior in the environment of the KASCADE-Grande experiment. Knowing
  the amplification factor and the gain of the LOPES antennas LOPES30
  is calibrated absolutely for systematic analyses of the radio emission.

Title: Combined LOPES and KASCADE-GRANDE Data Analysis
Authors: Haungs, A.; Apel, W. D.; Badea, F.; Bähren, L.; Bekk, K.;
   Bercuci, A.; Bertaina, M.; Biermann, P. L.; Blümer, J.; Bozdog, H.;
   Brancus, I. M.; Brüggemann, M.; Buchholz, P.; Buitink, S.; Butcher,
   H.; Chiavassa, A.; Daumiller, K.; De Bruyn, A. G.; De Vos, C. M.; Di
   Pierro, F.; Doll, P.; Engel, R.; Falcke, H.; Gemmeke, H.; Ghia, P. L.;
   Glasstetter, R.; Grupen, C.; Heck, D.; Hörandel, J. R.; Horneffer,
   A.; Huege, T.; Kampert, K. -H.; Kant, G. W.; Klein, U.; Kolotaev,
   Y.; Koopman, Y.; Krömer, O.; Kuijpers, J.; Lafebre, S.; Maier, G.;
   Mathes, H. J.; Mayer, H. J.; Milke, J.; Mitrica, B.; Morello, C.;
   Navarra, G.; Nehls, S.; Nigl, A.; Obenland, R.; Oehlschläger, J.;
   Ostapchenko, S.; Over, S.; Pepping, H. J.; Petcu, M.; Petrovic, J.;
   Pierog, T.; Plewnia, S.; Rebel, H.; Risse, A.; Roth, M.; Schieler,
   H.; Schoonderbeek, G.; Sima, O.; Stümpert, M.; Toma, G.; Trinchero,
   G. C.; Ulrich, H.; Van Buren, J.; Van Capellen, W.; Walkowiak, W.;
   Weindl, A.; Wijnholds, S.; Wochele, J.; Zabierowski, J.; Zensus,
   J. A.; Zimmermann, D.; Lopes Collaboration
Bibcode: 2006aren.conf..182H
Altcode:
  First analyses of coincident data of the LOPES (LOfar PrototypE Station)
  radio antennas with the particle air shower experiment KASCADE-Grande
  show basic correlations in the observed shower parameters, like the
  strength of the radio signal and the particle number, or comparing
  the estimated shower directions. In addition, an improvement of the
  experimental resolution of the shower parameters reconstructed by
  KASCADE-Grande can be obtained by including the data of the radio
  antennas. This important feature will be shown in this article
  explicitely by an example event.

Title: Radio Detection of Cosmic Rays with LOPES
Authors: Horneffer, A.; Apel, W. D.; Badea, F.; Bähren, Bekk, K.;
   Bercuci, A.; Beraina, M.; Biermann, P. L.; Blümer, J.; Bozdog, H.;
   Brancus, I. M.; Brüggemann, M.; Buchholz, P.; Buitink, S.; Butcher,
   H.; Chiavassa, A.; Daumiller, K.; De Bruyn, A. G.; De Vos, C. M.;
   Di Pierro, F.; Doll, P.; Engel, R.; Falcke, H.; Gemmeke, H.; Ghia,
   P. L.; Glasstetter, R.; Grupen, C.; Haungs, A.; Heck, D.; Hörandel,
   J. R.; Huege, T.; Kampert, K. -H.; Kant, G. W.; Klein, U.; Kolotaev,
   Y.; Koopman, Y.; Krömer, O.; Kuijpers, J.; Lafebre, S.; Maier, G.;
   Mathes, H. J.; Mayer, H. J.; Milke, J.; Mitrica, B.; Morello, C.;
   Navarra, G.; Nehls, S.; Nigl, A.; Obenland, R.; Oehlschläger, J.;
   Ostapchenko, S.; Over, S.; Pepping, H. J.; Petcu, M.; Petrovic, J.;
   Pierog, T.; Plewnia, S.; Rebel, H.; Risse, A.; Roth, M.; Schieler,
   H.; Schoonderbeek, G.; Sima, O.; Stümpert, M.; Toma, G.; Trinchero,
   G. C.; Ulrich, H.; Van Buren, J.; Van Capellen, W.; Walkowiak, W.;
   Weindl, A.; Wijnholds, S.; Wochele, J.; Zabierowski, J.; Zensus,
   J. A.; Zimmermann, D.
Bibcode: 2006aren.conf..168H
Altcode:
  Measuring radio pulses from cosmic ray air showers offers various
  new opportunities. New digital radio receivers allow measurements
  of these radio pulses even in environments that have lots of radio
  interference. With high bandwidth ADCs and fast data processing it is
  possible to store the whole waveform information in digital form and
  analyse transient events like air showers even after they have been
  recorded. Digital filtering and beam forming can be used to suppress the
  radio interference so that it is possible to measure the radio pulses
  even in radio loud environments. LOPES is a prototype station for the
  new digital radio interferometer LOFAR and is tailored to measure air
  showers. For this it is located at the site of the KASCADE-Grande air
  shower experiment. Already with the first phase of LOPES we have been
  able to measure radio pulses from air showers and show correlations
  between the radio pulse height and air shower parameters. <P />The first
  part gives an introduction and presents the science results of LOPES,
  while the second part presents the hard- and software that enables
  LOPES to detect air short pulses.

Title: Indirect Visibility of Gravitational Waves in
    Magnetohydrodynamic Plasmas
Authors: Moortgat, J.; Kuijpers, J.
Bibcode: 2005tsra.conf..326M
Altcode: 2005gr.qc.....3074M
  We propose a mechanism to make gravitational waves (GWs) visible
  in the electromagnetic domain. Gravitational waves that propagate
  through a strongly magnetized plasma interact with the plasma through
  its anisotropic stress-energy tensor and excite magnetohydrodynamic
  (MHD) wave modes. In catastrophic events such as the merger of a double
  neutron star binary, a large fraction of the total binding energy of
  the system is released in the form of GWs observable by LIGO, and the
  amount of energy transferred to the MHD waves is substantial. These
  modes, however, are excited at the same frequency as the GW and are not
  directly observable. In this paper we investigate radiation processes
  that operate in the presence of the gravitationally excited MHD waves
  and radiate in the radio regime accessible to LOFAR. We present order
  of magnitude estimates for the spectral flux of a merger detectable
  by a LOFAR.

Title: Frequency dependence of the drifting subpulses of PSR B0031-07
Authors: Smits, J. M.; Mitra, D.; Kuijpers, J.
Bibcode: 2005A&A...440..683S
Altcode: 2005astro.ph..6264S
  The well known drifter PSR B0031-07 is known to exhibit drifting
  subpulses where the spacing between the drift bands (P<SUB>3</SUB>)
  shows three distinct modes A, B and C corresponding to 12, 6 and 4
  s respectively. We have investigated periodicities and polarisation
  properties of PSR B0031-07 for a sequence of 2700 single pulses taken
  simultaneously at 328 MHz and 4.85 GHz. We found that mode A occurs
  simultaneously at these frequencies, while modes B and C only occur at
  328 MHz. However, when the pulsar is emitting in mode B at the lower
  frequency there is still emission at the higher frequency, hinting
  towards the presence of mode B emission at a weaker level. Further, we
  have established that modes A and B are associated with two orthogonal
  modes of polarisation, respectively. Based on these observations, we
  suggest a geometrical model where modes A and B at a given frequency
  are emitted in two concentric rings around the magnetic axis with mode
  B being nested inside mode A. Further, it is evident that this nested
  configuration is preserved across frequency with the higher frequency
  arising closer to the stellar surface compared to the lower one,
  consistent with the well known radius-to-frequency mapping operating
  in pulsars.

Title: An outreach project for LOFAR and cosmic ray detection.
Authors: Nigl, A.; Timmermans, C.; Schellart, P.; Kuijpers, J.;
   Falcke, H.; Horneffer, A.; de Vos, C. M.; Koopman, Y.; Pepping, H. J.;
   Schoonderbeek, G.
Bibcode: 2005AN....326..619N
Altcode:
  No abstract at ADS

Title: Detection and imaging of atmospheric radio flashes from cosmic
    ray air showers
Authors: Falcke, H.; Apel, W. D.; Badea, A. F.; Bähren, L.; Bekk, K.;
   Bercuci, A.; Bertaina, M.; Biermann, P. L.; Blümer, J.; Bozdog, H.;
   Brancus, I. M.; Buitink, S.; Brüggemann, M.; Buchholz, P.; Butcher,
   H.; Chiavassa, A.; Daumiller, K.; de Bruyn, A. G.; de Vos, C. M.; di
   Pierro, F.; Doll, P.; Engel, R.; Gemmeke, H.; Ghia, P. L.; Glasstetter,
   R.; Grupen, C.; Haungs, A.; Heck, D.; Hörandel, J. R.; Horneffer,
   A.; Huege, T.; Kampert, K. -H.; Kant, G. W.; Klein, U.; Kolotaev, Y.;
   Koopman, Y.; Krömer, O.; Kuijpers, J.; Lafebre, S.; Maier, G.; Mathes,
   H. J.; Mayer, H. J.; Milke, J.; Mitrica, B.; Morello, C.; Navarra, G.;
   Nehls, S.; Nigl, A.; Obenland, R.; Oehlschläger, J.; Ostapchenko,
   S.; Over, S.; Pepping, H. J.; Petcu, M.; Petrovic, J.; Plewnia, S.;
   Rebel, H.; Risse, A.; Roth, M.; Schieler, H.; Schoonderbeek, G.;
   Sima, O.; Stümpert, M.; Toma, G.; Trinchero, G. C.; Ulrich, H.;
   Valchierotti, S.; van Buren, J.; van Cappellen, W.; Walkowiak, W.;
   Weindl, A.; Wijnholds, S.; Wochele, J.; Zabierowski, J.; Zensus,
   J. A.; Zimmermann, D.
Bibcode: 2005Natur.435..313F
Altcode: 2005astro.ph..5383F
  The nature of ultrahigh-energy cosmic rays (UHECRs) at energies
  &gt;10<SUP>20</SUP>eV remains a mystery. They are likely to be of
  extragalactic origin, but should be absorbed within ~50Mpc through
  interactions with the cosmic microwave background. As there are no
  sufficiently powerful accelerators within this distance from the Galaxy,
  explanations for UHECRs range from unusual astrophysical sources
  to exotic string physics. Also unclear is whether UHECRs consist of
  protons, heavy nuclei, neutrinos or γ-rays. To resolve these questions,
  larger detectors with higher duty cycles and which combine multiple
  detection techniques are needed. Radio emission from UHECRs, on the
  other hand, is unaffected by attenuation, has a high duty cycle, gives
  calorimetric measurements and provides high directional accuracy. Here
  we report the detection of radio flashes from cosmic-ray air showers
  using low-cost digital radio receivers. We show that the radiation can
  be understood in terms of the geosynchrotron effect. Our results show
  that it should be possible to determine the nature and composition of
  UHECRs with combined radio and particle detectors, and to detect the
  ultrahigh-energy neutrinos expected from flavour mixing.

Title: Measurement of the shadowing of high-energy cosmic rays by
the Moon: A search for TeV-energy antiprotons
Authors: L3 Collaboration; Achard, P.; Adriani, O.; Aguilar-Benitez,
   M.; van den Akker, M.; Alcaraz, J.; Alemanni, G.; Allaby, J.; Aloisio,
   A.; Alviggi, M. G.; Anderhub, H.; Andreev, V. P.; Anselmo, F.; Arefiev,
   A.; Azemoon, T.; Aziz, T.; Bagnaia, P.; Bajo, A.; Baksay, G.; Baksay,
   L.; Bähr, J.; Baldew, S. V.; Banerjee, S.; Banerjee, Sw.; Barczyk, A.;
   Barillère, R.; Bartalini, P.; Basile, M.; Batalova, N.; Battiston, R.;
   Bay, A.; Becattini, F.; Becker, U.; Behner, F.; Bellucci, L.; Berbeco,
   R.; Berdugo, J.; Berges, P.; Bertucci, B.; Betev, B. L.; Biasini, M.;
   Biglietti, M.; Biland, A.; Blaising, J. J.; Blyth, S. C.; Bobbink,
   G. J.; Böhm, A.; Boldizsar, L.; Borgia, B.; Bottai, S.; Bourilkov,
   D.; Bourquin, M.; Braccini, S.; Branson, J. G.; Brochu, F.; Burger,
   J. D.; Burger, W. J.; Cai, X. D.; Capell, M.; Romeo, G. Cara; Carlino,
   G.; Cartacci, A.; Casaus, J.; Cavallari, F.; Cavallo, N.; Cecchi, C.;
   Cerrada, M.; Chamizo, M.; Chiarusi, T.; Chang, Y. H.; Chemarin, M.;
   Chen, A.; Chen, G.; Chen, G. M.; Chen, H. F.; Chen, H. S.; Chiefari,
   G.; Cifarelli, L.; Cindolo, F.; Clare, I.; Clare, R.; Coignet, G.;
   Colino, N.; Costantini, S.; de La Cruz, B.; Cucciarelli, S.; de
   Asmundis, R.; Déglon, P.; Debreczeni, J.; Degré, A.; Dehmelt, K.;
   Deiters, K.; della Volpe, D.; Delmeire, E.; Denes, P.; Denotaristefani,
   F.; de Salvo, A.; Diemoz, M.; Dierckxsens, M.; Ding, L. K.; Dionisi,
   C.; Dittmar, M.; Doria, A.; Dova, M. T.; Duchesneau, D.; Duda, M.;
   Duran, I.; Echenard, B.; Eline, A.; El Hage, A.; El Mamouni, H.;
   Engler, A.; Eppling, F. J.; Extermann, P.; Faber, G.; Falagan, M. A.;
   Falciano, S.; Favara, A.; Fay, J.; Fedin, O.; Felcini, M.; Ferguson,
   T.; Fesefeldt, H.; Fiandrini, E.; Field, J. H.; Filthaut, F.; Fisher,
   P. H.; Fisher, W.; Fisk, I.; Forconi, G.; Freudenreich, K.; Furetta,
   C.; Galaktionov, Yu.; Ganguli, S. N.; Garcia-Abia, P.; Gataullin,
   M.; Gentile, S.; Giagu, S.; Gong, Z. F.; Grabosch, H. J.; Grenier,
   G.; Grimm, O.; Groenstege, H.; Gruenewald, M. W.; Guida, M.; Guo,
   Y. N.; Gupta, V. K.; Gurtu, A.; Gutay, L. J.; Haas, D.; Haller, Ch.;
   Hatzifotiadou, D.; Hayashi, Y.; He, Z. X.; Hebbeker, T.; Hervé, A.;
   Hirschfelder, J.; Hofer, H.; Hofer, H.; Hohlmann, M.; Holzner, G.;
   Hou, S. R.; Huo, A. X.; Ito, N.; Jin, B. N.; Jindal, P.; Jing, C. L.;
   Jones, L. W.; de Jong, P.; Josa-Mutuberría, I.; Kantserov, V.; Kaur,
   M.; Kawakami, S.; Kienzle-Focacci, M. N.; Kim, J. K.; Kirkby, J.;
   Kittel, W.; Klimentov, A.; König, A. C.; Kok, E.; Korn, A.; Kopal,
   M.; Koutsenko, V.; Kräber, M.; Kuang, H. H.; Kraemer, R. W.; Krüger,
   A.; Kuijpers, J.; Kunin, A.; Ladron de Guevara, P.; Laktineh, I.;
   Landi, G.; Lebeau, M.; Lebedev, A.; Lebrun, P.; Lecomte, P.; Lecoq,
   P.; Le Coultre, P.; Le Goff, J. M.; Lei, Y.; Leich, H.; Leiste, R.;
   Levtchenko, M.; Levtchenko, P.; Li, C.; Li, L.; Li, Z. C.; Likhoded,
   S.; Lin, C. H.; Lin, W. T.; Linde, F. L.; Lista, L.; Liu, Z. A.;
   Lohmann, W.; Longo, E.; Lu, Y. S.; Luci, C.; Luminari, L.; Lustermann,
   W.; Ma, W. G.; Ma, X. H.; Ma, Y. Q.; Malgeri, L.; Malinin, A.; Maña,
   C.; Mans, J.; Martin, J. P.; Marzano, F.; Mazumdar, K.; McNeil, R. R.;
   Mele, S.; Meng, X. W.; Merola, L.; Meschini, M.; Metzger, W. J.; Mihul,
   A.; van Mil, A.; Milcent, H.; Mirabelli, G.; Mnich, J.; Mohanty, G. B.;
   Monteleoni, B.; Muanza, G. S.; Muijs, A. J. M.; Musicar, B.; Musy,
   M.; Nagy, S.; Nahnhauer, R.; Naumov, V. A.; Natale, S.; Napolitano,
   M.; Nessi-Tedaldi, F.; Newman, H.; Nisati, A.; Novak, T.; Nowak, H.;
   Ofierzynski, R.; Organtini, G.; Pal, I.; Palomares, C.; Paolucci,
   P.; Paramatti, R.; Parriaud, J. -F.; Passaleva, G.; Patricelli, S.;
   Paul, T.; Pauluzzi, M.; Paus, C.; Pauss, F.; Pedace, M.; Pensotti,
   S.; Perret-Gallix, D.; Petersen, B.; Piccolo, D.; Pierella, F.;
   Pieri, M.; Pioppi, M.; Piroué, P. A.; Pistolesi, E.; Plyaskin, V.;
   Pohl, M.; Pojidaev, V.; Pothier, J.; Prokofiev, D.; Quartieri, J.;
   Qing, C. R.; Rahal-Callot, G.; Rahaman, M. A.; Raics, P.; Raja, N.;
   Ramelli, R.; Rancoita, P. G.; Ranieri, R.; Raspereza, A.; Ravindran,
   K. C.; Razis, P.; Ren, D.; Rescigno, M.; Reucroft, S.; Rewiersma, P.;
   Riemann, S.; Riles, K.; Roe, B. P.; Rojkov, A.; Romero, L.; Rosca, A.;
   Rosemann, C.; Rosier-Lees, S.; Rosenbleck, C.; Roth, S.; Rubio, J. A.;
   Ruggiero, G.; Rykaczewski, H.; Saidi, R.; Sakharov, A.; Saremi, S.;
   Sarkar, S.; Salicio, J.; Sanchez, E.; Schäfer, C.; Schegelsky, V.;
   Schmitt, V.; Schoeneich, B.; Schopper, H.; Schotanus, D. J.; Sciacca,
   C.; Servoli, L.; Shen, C. Q.; Shevchenko, S.; Shivarov, N.; Shoutko,
   V.; Shumilov, E.; Shvorob, A.; Son, D.; Souga, C.; Spillantini, P.;
   Steuer, M.; Stickland, D. P.; Stoyanov, B.; Straessner, A.; Sudhakar,
   K.; Sulanke, H.; Sultanov, G.; Sun, L. Z.; Sushkov, S.; Suter, H.;
   Swain, J. D.; Szillasi, Z.; Tang, X. W.; Tarjan, P.; Tauscher, L.;
   Taylor, L.; Tellili, B.; Teyssier, D.; Timmermans, C.; Ting, Samuel
   C. C.; Ting, S. M.; Tonwar, S. C.; Tóth, J.; Trowitzsch, G.; Tully,
   C.; Tung, K. L.; Ulbricht, J.; Unger, M.; Valente, E.; Verkooijen,
   H.; van de Walle, R. T.; Vasquez, R.; Veszpremi, V.; Vesztergombi,
   G.; Vetlitsky, I.; Vicinanza, D.; Viertel, G.; Villa, S.; Vivargent,
   M.; Vlachos, S.; Vodopianov, I.; Vogel, H.; Vogt, H.; Vorobiev, I.;
   Vorobyov, A. A.; Wadhwa, M.; Wang, R. G.; Wang, Q.; Wang, X. L.; Wang,
   X. W.; Wang, Z. M.; Weber, M.; van Wijk, R.; Wijnen, T. A. M.; Wilkens,
   H.; Wynhoff, S.; Xia, L.; Xu, Y. P.; Xu, J. S.; Xu, Z. Z.; Yamamoto,
   J.; Yang, B. Z.; Yang, C. G.; Yang, H. J.; Yang, M.; Yang, X. F.;
   Yao, Z. G.; Yeh, S. C.; Yu, Z. Q.; Zalite, An.; Zalite, Yu.; Zhang,
   C.; Zhang, F.; Zhang, J.; Zhang, S.; Zhang, Z. P.; Zhao, J.; Zhou,
   S. J.; Zhu, G. Y.; Zhu, R. Y.; Zhu, Q. Q.; Zhuang, H. L.; Zichichi,
   A.; Zimmermann, B.; Zöller, M.; Zwart, A. N. M.
Bibcode: 2005APh....23..411L
Altcode: 2005astro.ph..3472L
  The shadowing of high-energy cosmic rays by the Moon has been observed
  with a significance of 9.4 standard deviations with the L3 + C muon
  spectrometer at CERN. A significant effect of the Earth magnetic field
  is observed. Since no event deficit on the east side of the Moon has
  been observed, an upper limit at 90% confidence level on the antiproton
  to proton ratio of 0.11 is obtained for primary energies around 1 TeV.

Title: Radio emission of highly inclined cosmic ray air showers
    measured with LOPES
Authors: Petrovic, J.; Apel, W. D.; Badea, F.; Bähren, L.; Bekk, K.;
   Bercuci, A.; Bertaina, M.; Biermann, P. L.; Blümer, J.; Bozdog, H.;
   Brancus, I. M.; Buitink, S.; Brüggemann, M.; Buchholz, P.; Butcher,
   H.; Chiavassa, A.; Daumiller, K.; de Bruyn, A. G.; de Vos, C. M.;
   Di Pierro, F.; Doll, P.; Engel, R.; Falcke, H.; Gemmeke, H.; Ghia,
   P. L.; Glasstetter, R.; Grupen, C.; Haungs, A.; Heck, D.; Hörandel,
   J. R.; Horneffer, A.; Huege, T.; Kampert, K. -H.; Kant, G. W.; Klein,
   U.; Kolotaev, Y.; Koopman, Y.; Krömer, B.; Kuijpers, J.; Lafebre,
   S.; Maier, G.; Mathes, H. J.; Mayer, H. J.; Milke, J.; Mitrica,
   B.; Morello, C.; Navarra, G.; Nehls, S.; Nigl, A.; Obenland, R.;
   Oehlschläger, J.; Ostapchenko, S.; Over, S.; Pepping, H. J.; Petcu,
   M.; Pierog, T.; Plewnia, S.; Rebel, H.; Risse, A.; Roth, M.; Schieler,
   H.; Schoonderbeek, G.; Sima, O.; Stümpert, M.; Toma, G.; Trinchero,
   G. C.; Ulrich, H.; Valchierotti, S.; van Buren, J.; van Capellen, W.;
   Walkowiak, W.; Weindl, A.; Winjnholds, S.; Wochele, J.; Zabierowski,
   J.; Zensus, J. A.; Zimmermann, D.
Bibcode: 2005ICRC....6..337P
Altcode: 2005ICRC...29f.337P
  No abstract at ADS

Title: Radio Detection of High-Energy Cosmic Rays: LOPES
Authors: Haungs, A.; Apel, W. D.; Badea, F.; Bekk, K.; Blümer, J.;
   Bozdog, H.; Daumiller, K.; Doll, P.; Engel, R.; Heck, D.; Mathes,
   H. J.; Mayer, H. J.; Milke, J.; Nehls, S.; Obenland, R.; Oehlschläger,
   J.; Ostapchenko, S.; Plewnia, S.; Rebel, H.; Schieler, H.; Ulrich,
   H.; van Buren, J.; Weindl, A.; Wochele, J.; Bähren, L.; Butcher,
   H.; de Bruyn, G.; de Vos, C. M.; Falcke, H.; Kant, G. W.; Koopman,
   Y.; Pepping, H. J.; Schoonderbeek, G.; van Capellen, W.; Wijnholds,
   S.; Bercuci, A.; Brancus, I. M.; Mitrica, B.; Petcu, M.; Sima,
   O.; Toma, G.; Bertaina, M.; Chiavassa, A.; di Pierro, F.; Navarra,
   G.; Valchierotti, S.; Biermann, P. L.; Horneffer, A.; Huege, T.;
   Zensus, J. A.; Brüggemann, M.; Buchholz, P.; Kolotaev, Y.; Over, S.;
   Walkowiak, W.; Zimmermann, D.; Buitink, S.; Kuijpers, J.; Lafebre, S.;
   Nigl, A.; Petrovic, J.; Gemmeke, H.; Krömer, O.; Ghia, P. L.; Morello,
   C.; Trinchero, G. C.; Glasstetter, R.; Kampert, K. -H.; Hörandel,
   J. R.; Roth, M.; Stümpert, M.; Klein, U.; Risse, A.; Zabierowski, J.
Bibcode: 2005tsra.conf..687H
Altcode:
  The detection of radio pulses emitted in the atmosphere during the
  air shower development of high-energy primary cosmic rays is the task
  of the LOPES (LOFAR Prototype Station) project. LOFAR (Low Frequency
  Array) is a new digital radio interferometer under development using
  high bandwidth ADCs and fast data processing to filter out most of the
  interference. By storing the whole waveform information in digital form
  transient events like air showers can be analyzed even after they have
  been recorded. To test this technology and to demonstrate its ability
  to measure air showers a LOPES is set up to operate in conjunction
  with an existing air shower experiment (KASCADE-Grande). The LOPES
  antennas are operating in the frequency range of 40-80 MHz. For several
  air-shower events a coincident and coherent signal has been found and
  a preliminary analysis has already been performed. The main goal of
  further investigations is to calibrate the radio signal with help of
  the observables of the individual air-showers given by KASCADE-Grande.

Title: An Outreach Project for LOFAR and Cosmic Ray Detection
Authors: Nigl, A.; Timmermans, C.; Schllarts, P.; Kuijpers, J.;
   Falcke, H.; Horneffer, A.; de Vos, C. M.; Koopman, Y.; Pepping, H. J.;
   Schoonderbeek, G.
Bibcode: 2005ICRC....6..341N
Altcode: 2005ICRC...29f.341N
  No abstract at ADS

Title: LOPES30: A digital antenna array for measuring high-energy
    cosmic ray air showers
Authors: Nehls, S.; Apel, W. D.; Badea, F.; Bähren, L.; Bekk, K.;
   Bercuci, A.; Bertaina, M.; Biermann, P. L.; Blümer, J.; Bozdog, H.;
   Brancus, I. M.; Buitink, S.; Brüggemann, M.; Buchholz, P.; Butcher,
   H.; Chiavassa, A.; Daumiller, K.; de Bruyn, A. G.; de Vos, C. M.;
   Di Pierro, F.; Doll, P.; Engel, R.; Falcke, H.; Gemmeke, H.; Ghia,
   P. L.; Glasstetter, R.; Grupen, C.; Haungs, A.; Heck, D.; Hörandel,
   J. R.; Horneffer, A.; Huege, T.; Kampert, K. -H.; Kant, G. W.; Klein,
   U.; Kolotaev, Y.; Koopman, Y.; Krömer, O.; Kuijpers, J.; Lafebre,
   S.; Maier, G.; Mathes, H. J.; Mayer, H. J.; Milke, J.; Mitrica, B.;
   Morello, C.; Navarra, G.; Nigl, A.; Obenland, R.; Oehlschläger, J.;
   Ostapchenko, S.; Over, S.; Pepping, H. J.; Petcu, M.; Petrovic, J.;
   Pierog, T.; Plewnia, S.; Rebel, H.; Risse, A.; Roth, M.; Schieler,
   H.; Schoonderbeek, G.; Sima, O.; Stümpert, M.; Toma, G.; Trinchero,
   G. C.; Ulrich, H.; Valchierotti, S.; van Buren, J.; van Capellen, W.;
   Walkowiak, W.; Weindl, A.; Wijnholds, S.; Wochele, J.; Zabierowski,
   J.; Zensus, J. A.; Zimmermann, D.
Bibcode: 2005ICRC....8...45N
Altcode: 2005ICRC...29h..45N
  No abstract at ADS

Title: Gravitational Wave Interactions with Magnetized Plasmas
Authors: Moortgat, Joachim; Kuijpers, Jan
Bibcode: 2005ASIB..210..103M
Altcode: 2004gr.qc....11128M; 2005esns.conf..103M
  Gravitational waves (GWs) propagating through a uniformly magnetized
  plasma interact directly with the magnetic field and excite
  magnetohydrodynamic (MHD) waves with both electromagnetic and matter
  components. We study this process for arbitrary geometry in the
  MHD approximation and find that all three fundamental MHD modes --
  slow and fast magnetosonic, and Alfven -- are excited depending on
  both the polarization of the GW and the orientation of the ambient
  magnetic field. The latter two modes can interact coherently with the
  GW resulting in damping of the GW and linear growth of the plasma waves.

Title: A Cosmic Ray Trigger for LOFAR
Authors: Lafebre, S.; Nigl, A.; Apel, W. D.; Badea, F.; Bähren, L.;
   Bekk, K.; Bercuci, A.; Bertaina, M.; Biermann, P. L.; Blümer, J.;
   Bozdog, H.; Brancus, I. M.; Buitink, S.; Brüggemann, M.; Buchholz,
   P.; Butcher, H.; Chiavassa, A.; Daumiller, K.; de Bruyn, A. G.; de
   Vos, C. M.; Di Pierro, F.; Doll, P.; Engel, R.; Falcke, H.; Gemmeke,
   H.; Ghia, P. L.; Glasstetter, R.; Grupen, C.; Haungs, A.; Heck, D.;
   Hörandel, J. R.; Horneffer, A.; Huege, T.; Kampert, K. -H.; Kant,
   G. W.; Klein, U.; Kolotaev, Y.; Koopman, Y.; Krömer, O.; Kuijpers,
   J.; Maier, G.; Mathes, H. J.; Mayer, H. J.; Milke, J.; Mitrica, B.;
   Morello, C.; Navarra, G.; Nehls, S.; Obenland, R.; Oehlschläger, J.;
   Ostapchenko, S.; Over, S.; Pepping, H. J.; Petcu, M.; Petrovic, J.;
   Pierog, T.; Plewnia, S.; Rebel, H.; Risse, A.; Roth, M.; Schieler,
   H.; Schoonderbeek, G.; Sima, O.; Stümpert, M.; Toma, G.; Trinchero,
   G. C.; Ulrich, H.; Valchierotti, S.; van Buren, J.; van Capellen, W.;
   Walkowiak, W.; Weindl, A.; Wijnholds, S.; Wochele, J.; Zabierowski,
   J.; Zensus, J. A.; Zimmermann, D.
Bibcode: 2005ICRC....8..245N
Altcode: 2005ICRC...29h.245N
  No abstract at ADS

Title: Cosmic Ray Trigger for LOFAR: First results
Authors: Lafebre, S.; Nigl, A.; Apel, W. D.; Badea, F.; Bähren, L.;
   Bekk, K.; Bercuci, A.; Bertaina, M.; Biermann, P. L.; Blümer, J.;
   Bozdog, H.; Brancus, I. M.; Buitink, S.; Brüggemann, M.; Buchholz,
   P.; Butcher, H.; Chiavassa, A.; Daumiller, K.; de Bruyn, A. G.; de
   Vos, C. M.; Di Pierro, F.; Doll, P.; Engel, R.; Falcke, H.; Gemmeke,
   H.; Ghia, P. L.; Glasstetter, R.; Grupen, C.; Haungs, A.; Heck, D.;
   Hörandel, J. R.; Horneffer, A.; Huege, T.; Kampert, K. -H.; Kant,
   G. W.; Klein, U.; Kolotaev, Y.; Koopman, Y.; Krömer, O.; Kuijpers,
   J.; Maier, G.; Mathes, H. J.; Mayer, H. J.; Milke, J.; Mitrica, B.;
   Morello, C.; Navarra, G.; Nehls, S.; Obenland, R.; Oehlschläger, J.;
   Ostapchenko, S.; Over, S.; Pepping, H. J.; Petcu, M.; Petrovic, J.;
   Pierog, T.; Plewnia, S.; Rebel, H.; Risse, A.; Roth, M.; Schieler,
   H.; Schoonderbeek, G.; Sima, O.; Stümpert, M.; Toma, G.; Trinchero,
   G. C.; Ulrich, H.; Valchierotti, S.; van Buren, J.; van Capellen, W.;
   Walkowiak, W.; Weindl, A.; Wijnholds, S.; Wochele, J.; Zabierowski,
   J.; Zensus, J. A.; Zimmermann, D.
Bibcode: 2005ICRC....8..249L
Altcode: 2005ICRC...29h.249L
  No abstract at ADS

Title: Electric field influence on the radio emission of air showers
Authors: Buitink, S.; Apel, W. D.; Badea, F.; Bähren, L.; Bekk, K.;
   Bercuci, A.; Bertaina, M.; Biermann, P. L.; Blümer, J.; Bozdog, H.;
   Brancus, I. M.; Brüggemann, M.; Buchholz, P.; Butcher, H.; Chiavassa,
   A.; Daumiller, K.; de Bruyn, A. G.; de Vos, C. M.; Di Pierro, F.; Doll,
   P.; Engel, R.; Falcke, H.; Gemmeke, H.; Ghia, P. L.; Glasstetter,
   R.; Grupen, C.; Haungs, A.; Heck, D.; Hörandel, J. R.; Horneffer,
   A.; Huege, T.; Kampert, K. -H.; Kant, G. W.; Klein, U.; Kolotaev,
   Y.; Koopman, Y.; Krömer, B.; Kuijpers, J.; Lafebre, S.; Maier, G.;
   Mathes, H. J.; Mayer, H. J.; Milke, J.; Mitrica, B.; Morello, C.;
   Navarra, G.; Nehls, S.; Nigl, A.; Obenland, R.; Oehlschläger, J.;
   Ostapchenko, S.; Over, S.; Pepping, H. J.; Petcu, M.; Petrovic, J.;
   Pierog, T.; Plewnia, S.; Rebel, H.; Risse, A.; Roth, M.; Schieler,
   H.; Schoonderbeek, G.; Sima, O.; Stümpert, M.; Toma, G.; Trinchero,
   G. C.; Ulrich, H.; Valchierotti, S.; van Buren, J.; van Capellen, W.;
   Walkowiak, W.; Weindl, A.; Winjnholds, S.; Wochele, J.; Zabierowski,
   J.; Zensus, J. A.; Zimmermann, D
Bibcode: 2005ICRC....6..333B
Altcode: 2005ICRC...29f.333B
  No abstract at ADS

Title: Fluctuations in the EAS radio signal derived with improved
    Monte Carlo simulations based on CORSIKA
Authors: Huege, T.; Apel, W. D.; Badea, F.; Bähren, L.; Bekk, K.;
   Bercuci, A.; Bertaina, M.; Biermann, P. L.; Blümer, J.; Bozdog,
   H.; Brancus, I. M.; Buitnink, S.; Brüggemann, M.; Buchholz, P.;
   Butcher, H.; Chiavassa, A.; Daumiller, K.; de Bruyn, A. G.; de Vos,
   C. M.; Di Pierro, F.; Doll, P.; Engel, R.; Falcke, H.; Gemmeke,
   H.; Ghia, P. L.; Glasstetter, R.; Grupen, C.; Haungs, A.; Heck, D.;
   Hörandel, J. R.; Horneffer, A.; Kuijpers, J.; Lafebre, S.; Maier,
   G.; Mathes, H. J.; Mayer, H. J.; Milke, J.; Mitrica, B.; Morello, C.;
   Navarra, G.; Nehls, S.; Nigl, A.; Obenland, R.; Oehlschläger, J.;
   Ostapchenko, S.; Over, S.; Pepping, H. J.; Petcu, M.; Petrovic, J.;
   Pierog, T.; Plewnia, S.; Rebel, H.; Risse, A.; Roth, M.; Schieler,
   H.; Schoonderbeek, G.; Sima, O.; Stümpert, M.; sToma, G.; Trinchero,
   G. C.; Ulrich, H.; Valchierotti, S.; van Buren, J.; van Capellen, W.;
   Walkowiak, W.; Weindl, A.; Wijnholds, S.; Wochele, J.; Zabierowski,
   J.; Zensus, J. A.; Zimmermann, D.
Bibcode: 2005ICRC....7..107H
Altcode: 2005ICRC...29g.107H; 2005astro.ph..7026H
  Cosmic ray air showers are known to emit pulsed radio emission which
  can be understood as coherent geosynchrotron radiation arising from
  the deflection of electron-positron pairs in the earth's magnetic
  field. Here, we present simulations carried out with an improved
  version of our Monte Carlo code for the calculation of geosynchrotron
  radiation. Replacing the formerly analytically parametrised longitudinal
  air shower development with CORSIKA-generated longitudinal profiles,
  we study the radio flux variations arising from inherent fluctuations
  between individual air showers. Additionally, we quantify the dependence
  of the radio emission on the nature of the primary particle by comparing
  the emission generated by proton- and iron-induced showers. This is
  only the first step in the incorporation of a more realistic air shower
  model into our Monte Carlo code. The inclusion of highly realistic
  CORSIKA-based particle energy, momentum and spatial distributions
  together with an analytical treatment of ionisation losses will soon
  allow simulations of the radio emission with unprecedented detail. This
  is especially important to assess the emission strengths at large
  radial distances, needed for event-to-event comparisons of the radio
  signals measured by LOPES in conjunction with KASCADE-Grande and for
  considerations regarding large arrays of radio antennas intended
  to measure the radio emission from ultra-high energy cosmic rays,
  as with LOFAR or in the Pierre Auger Observatory.

Title: Remote event analyses of LOPES-10
Authors: Badea, A. F.; Apel, W. D.; Bähren, L.; Bekk, K.; Bercuci, A.;
   Bertaina, M.; Biermann, P. L.; Blümer, J.; Bozdog, H.; Brancus, I. M.;
   Buitink, S.; Brüggemann, M.; Buchholz, P.; Butcher, H.; Chiavassa, A.;
   Daumiller, K.; de Bruyn, A. G.; de Vos, C. M.; Di Pierro, F.; Doll,
   P.; Engel, R.; Falcke, H.; Gemmeke, H.; Ghia, P. L.; Glasstetter,
   R.; Grupen, C.; Haungs, A.; Heck, D.; Hörandel, J. R.; Horneffer,
   A.; Huege, T.; Kampert, K. -H.; Kant, G. W.; Klein, U.; Kolotaev,
   Y.; Koopman, Y.; Krömer, O.; Kuijpers, J.; Lafebre, S.; Maier, G.;
   Mathes, H. J.; Mayer, H. J.; Milke, J.; Mitrica, B.; Morello, C.;
   Navarra, G.; Nehls, S.; Nigl, A.; Obenland, R.; Oehlschläger, J.;
   Ostapchenko, S.; Over, S.; Pepping, H. J.; Petcu, M.; Petrovic, J.;
   Pierog, T.; Plenia, S.; Rebel, H.; Risse, A.; Roth, M.; Schieler,
   H.; Schoonderbeek, G.; Sima, O.; Stüpert, M.; Toma, G.; Trinchero,
   G. C.; Ulrich, H.; Valchierotti, S.; van Buren, J.; van Capellen, W.;
   Walkowiak, W.; Weindl, A.; Wiknholds, S.; Wochele, J.; Zabierowski,
   J.; Zensuz, J. A.; Zimmermann, D.
Bibcode: 2005ICRC....6..277B
Altcode: 2005ICRC...29f.277B
  No abstract at ADS

Title: First determination of the reconstruction resolution of an
    EAS radio detector
Authors: Badea, A. F.; Apel, W. D.; Bähren, L.; Bekk, K.; Bercuci, A.;
   Bertaina, M.; Biermann, P. L.; Blümer, J.; Bozdog, H.; Brancus, I. M.;
   Buitink, S.; Brüggemann, M.; Buchholz, P.; Butcher, H.; Chiavassa, A.;
   Daumiller, K.; de Bruyn, A. G.; de Vos, C. M.; Di Pierro, F.; Doll,
   P.; Engel, R.; Falcke, H.; Gemmeke, H.; Ghia, P. L.; Glasstetter,
   R.; Grupen, C.; Haungs, A.; Heck, D.; Hörandel, J. R.; Horneffer,
   A.; Huege, T.; Kampert, K. -H.; Kant, G. W.; Klein, U.; Kolotaev,
   Y.; Koopman, Y.; Krömer, O.; Kuijpers, J.; Lafebre, S.; Maier, G.;
   Mathes, H. J.; Mayer, H. J.; Milke, J.; Mitrica, B.; Morello, C.;
   Navarra, G.; Nehls, S.; Nigl, A.; Obenland, R.; Oehlschläger, J.;
   Ostapchenko, S.; Over, S.; Pepping, H. J.; Petcu, M.; Petrovic, J.;
   Pierog, T.; Plewnia, S.; Rebel, H.; Risse, A.; Roth, M.; Schieler,
   H.; Schoonderbeek, G.; Sima, O.; Stümpert, M.; Toma, G.; Trinchero,
   G. C.; Ulrich, H.; Valchierotti, S.; van Buren, J.; van Capellen, W.;
   Walkowiak, W.; Weindl, A.; Wijnholds, S.; Wochele, J.; Zabierowski,
   J.; Zensus, J. A.; Zimmermann, D.
Bibcode: 2005ICRC....6..273B
Altcode: 2005ICRC...29f.273B
  No abstract at ADS

Title: Detection of radio pulses from extensive air showers
Authors: Horneffer, A.; Apel, W. D.; Badea, F.; Bähren, L.; Bekk, K.;
   Bercuci, A.; Bertaina, M.; Biermann, P. L.; Blümer, J.; Bozdog, H.;
   Brancus, I. M.; Buitink, S.; Brüggemann, M.; Buchholz, P.; Butcher,
   H.; Chiavassa, A.; Daumiller, K.; de Bruyn, A. G.; de Vos, C. M.; Di
   Pierro, F.; Doll, P.; Engel, R.; Falcke, H.; Koopman, Y.; Krömer,
   O.; Kuijpers, J.; Lafebre, S.; Maier, G.; Mathes, H. J.; Mayer,
   H. J.; Milke, J.; Mitrica, B.; Morello, C.; Navarra, G.; Nehls, S.;
   Nigl, A.; Obenland, R.; Oehlschläger, J.; Ostapchenko, S.; Over,
   S.; Pepping, H. J.; Petcu, M.; Petrovic, J.; Pierog, T.; Plewnia,
   S.; Rebel, H.; Risse, A.; Roth, M.; Schieler, H.; Schoonderbeek,
   G.; Sima, O.; Stümpert, M.; Toma, G.; Trinchero, G. C.; Ulrich,
   H.; Valchierotti, S.; van Buren, J.; van Capellen, W.; Walkowiak,
   W.; Weindl, A.; Wijnholds, S.; Wochele, J.; Zabierowski, J.; Zensus,
   J. A.; Zimmermann, D.
Bibcode: 2005ICRC....6..285H
Altcode: 2005ICRC...29f.285H
  No abstract at ADS

Title: A free-electron laser in the pulsar magnetosphere
Authors: Fung, P. K.; Kuijpers, J.
Bibcode: 2004A&A...422..817F
Altcode: 2004astro.ph..5345F
  We have studied systematically the free-electron laser in the context
  of high brightness pulsar radio emission. In this paper, we have
  numerically examined the case where a transverse electromagnetic
  wave is distorting the motion of a relativistic electron beam while
  travelling over one stellar radius (≈10 km). For different sets
  of parameters, coherent emission is generated by bunches of beam
  electrons in the radio domain, with bandwidths of 3 GHz. Pulse power
  often reached 10<SUP>13</SUP> W, which corresponds with brightness
  temperature of 10<SUP>30</SUP> K. The duration of these pulses is of
  the order of nanoseconds. In the context of pulsar radio emission,
  our results indicate that the laser can produce elementary bursts of
  radiation which build up the observed microstructures of a few tens
  of microseconds duration. The process is sensitive mostly to the beam
  particles energy, number density and the background magnetic field,
  but much less so to the transverse wave parameters. We demonstrate
  that the operation of a free-electron laser with a transverse
  electromagnetic wiggler in the pulsar magnetosphere occurs preferably
  at moderate Lorentz factors γ ≥ 100, high beam density n ≳
  0.1;n<SUB>GJ</SUB>(r<SUB>*</SUB>) where n<SUB>GJ</SUB>(r<SUB>*</SUB>)
  is the Goldreich-Julian density at a stellar radius r<SUB>*</SUB>,
  and finally, at large altitude where the background magnetic field
  is low B<SUB>0</SUB> ≤ 10<SUP>-2</SUP>;T. <P />Appendix A is only
  available in electronic form at <P />http://www.edpsciences.org

Title: Gravitational waves in magnetized relativistic plasmas
Authors: Moortgat, J.; Kuijpers, J.
Bibcode: 2004PhRvD..70b3001M
Altcode: 2004gr.qc.....5086M
  We study the propagation of gravitational waves (GW’s) in a uniformly
  magnetized plasma at arbitrary angles to the magnetic field. No a
  priori assumptions are made about the temperature, and we consider
  both a plasma at rest and a plasma flowing out at ultrarelativistic
  velocities. In the 3+1 orthonormal tetrad description, we find that
  all three fundamental low-frequency plasma wave modes are excited by
  the GW’s. Alfvén waves are excited by a × polarized GW, whereas the
  slow and fast magnetoacoustic modes couple to the + polarization. The
  slow mode, however, does not interact coherently with the GW. The
  most relevant wave mode is the fast magnetoacoustic mode which in
  a strongly magnetized plasma has a vanishingly small phase lag with
  respect to the GW allowing for coherent interaction over large length
  scales. When the background magnetic field is almost, but not entirely,
  parallel to the GW’s direction of propagation even the Alfvén waves
  grow to first order in the GW amplitude. Finally, we calculate the
  growth of the magnetoacoustic waves and the damping of the GW.

Title: Lofar: a New Radio Telescope for Low Frequency Radio
Observations:. Science and Project Status
Authors: Röttgering, H.; de Bruyn, A. G.; Fender, R. P.; Kuijpers,
   J.; van Haarlem, M. P.; Johnston-Hollitt, M.; Miley, G. K.
Bibcode: 2003tsra.symp...69R
Altcode: 2003astro.ph..7240R
  LOFAR, the Low Frequency Array, is a large radio telescope consisting
  about 100 soccer field sized antenna stations spread over a region of
  400 km in diameter. It will operate in the frequency range from ~ 10 to
  240 MHz, with a resolution at 240 MHz of better than an arcsecond. Its
  superb sensitivity will allow for a broad range of astrophysical
  studies. In this contribution we first discuss four major areas of
  astrophysical research in which LOFAR will undoubtedly make important
  contributions: reionisation, distant galaxies and AGNs, transient radio
  sources and cosmic rays. Subsequently, we will discuss the technical
  concept of the instrument and the status of the LOFAR project.

Title: On the search for coherent radiation from radio pulsars
Authors: Smits, J. M.; Stappers, B. W.; Macquart, J. -P.; Ramachandran,
   R.; Kuijpers, J.
Bibcode: 2003A&A...405..795S
Altcode: 2003astro.ph..6306S
  We have examined data from pulsars B0950+08 and B0329+54 for evidence
  of temporally coherent radiation using the modified coherence function
  (MCF) technique of \citet{Jenet}. We consider the influence of both
  instrumental bandpass and interstellar propagation effects. Even after
  removal of the effects due to the instrumental bandpass, we detect a
  signature in the MCF of our PSR B0329+54 data which is consistent with
  the definition of a coherent signal. However, we model the effects
  due to interstellar scintillation for this pulsar and show that it
  reproduces the observed signature. In particular, the temporal coherence
  time is close to the reciprocal of the decorrelation bandwidth due to
  diffractive scintillation. Furthermore, comparison of the coherence
  times of three pulsars reported by \citet{Jenet} with their expected
  diffractive decorrelation bandwidths suggests that the detection of
  coherence in these pulsars is also likely a result of interstellar
  scintillation, and is not intrinsic to the pulsars.

Title: Gravitational and magnetosonic waves in gamma-ray bursts
Authors: Moortgat, J.; Kuijpers, J.
Bibcode: 2003A&A...402..905M
Altcode: 2003gr.qc.....2055M
  One of the possible sources of gamma-ray bursts (GRBs) are merging,
  compact neutronstar binaries. More than 90% of the binding energy of
  such a binary is released in the form of gravitational waves (GWs) in
  the last few seconds of the spiral-in phase before the formation of a
  black hole. In this article we investigate whether a fraction of this GW
  energy is transferred to magnetohydrodynamic waves in the magnetized
  plasma wind around the binary. Using the 3+1 orthonormal tedrad
  formalism, we study the propagation of a monochromatic, plane fronted,
  linearly polarized GW perpendicular to the ambient magnetic field in an
  ultra-relativistic wind, first in the comoving and then in the observer
  frame. A closed set of general relativistic magnetohydrodynamic (GRM)
  equations is derived in the form of conservation laws for electric
  charge, matter energy, momentum and magnetic energy densities. We
  linearize the GRM equations under the action of a monochromatic GW,
  which acts as a driver and find that fast magneto-acoustic waves grow,
  with amplitudes proportional to the GW amplitude and frequency and
  the strength of the background magnetic field.

Title: Gravitational Wave Interaction with Gamma-Ray Burst Plasma.
Authors: Moortgat, Joachim B.; Kuijpers, Jan
Bibcode: 2003IAUJD...1E...3M
Altcode:
  In a merging binary scenario for gamma-ray bursts most of the
  binding energy is released in the form of gravitational waves
  in the last seconds before the collapse to a black hole. In an
  attempt to investigate the nature of the central engine we consider
  neutronstar-neutronstar mergers and apply the general relativistic
  3+1 formalism to the interaction of the gravitational waves with the
  ultra-relativistic wind of magnetized plasma around the binary. We
  show that these waves distort the magnetic field frozen into the plasma
  and excite growing magnetosonic waves in the wind. Already before the
  merger the binary is embedded in a relativistically expanding magnetized
  wind of (mainly) leptons from the orbiting neutronstars so even a
  small transfer of gravitational wave energy to the wind may result in
  interesting observational signatures of a gamma-ray bursts fireball.

Title: Preface (Solar variability: from core to outer frontiers)
Authors: Kuijpers, Jan
Bibcode: 2002ESASP.506D..21K
Altcode: 2002svco.confD..21K; 2002ESPM...10...21K; 2002ESASP.506.....K
  No abstract at ADS

Title: The L3+C detector, a unique tool-set to study cosmic rays
Authors: Adriani, O.; van den Akker, M.; Banerjee, S.; Bähr, J.;
   Betev, B.; Bourilkov, D.; Bottai, S.; Bobbink, G.; Cartacci, A.;
   Chemarin, M.; Chen, G.; Chen, H. S.; Chiarusi, T.; Dai, C. J.; Ding,
   L. K.; Duran, I.; Faber, G.; Fay, J.; Grabosch, H. J.; Groenstege,
   H.; Guo, Y. N.; Gupta, S.; Haller, Ch.; Hayashi, Y.; He, Z. X.;
   Hebbeker, T.; Hofer, H.; Hoferjun, H.; Huo, A. X.; Ito, N.; Jing,
   C. L.; Jones, L.; Kantserov, V.; Kawakami, S.; Kittel, W.; König,
   A. C.; Kok, E.; Korn, A.; Kuang, H. H.; Kuijpers, J.; Ladron de
   Guevara, P.; Le Coultre, P.; Lei, Y.; Leich, H.; Leiste, R.; Li, D.;
   Li, L.; Li, Z. C.; Liu, Z. A.; Liu, H. T.; Lohmann, W.; Lu, Y. S.;
   Ma, X. H.; Ma, Y. Q.; van Mil, A.; Monteleoni, B.; Nahnhauer, R.;
   Pauss, F.; Parriaud, J. -F.; Petersen, B.; Pohl, M.; Qing, C. R.;
   Ramelli, R.; Ravindran, K. C.; Rewiersma, P.; Rojkov, A.; Saidi, R.;
   Schmitt, V.; Schöneich, B.; Schotanus, D. J.; Shen, C. Q.; Sulanke,
   H.; Tang, X. W.; Timmermans, C.; Tonwar, S.; Trowitzsch, G.; Unger,
   M.; Verkooijen, H.; Wang, X. L.; Wang, X. W.; Wang, Z. M.; van Wijk,
   R.; Wijnen, Th. A. M.; Wilkens, H.; Xu, Y. P.; Xu, Z. Z.; Yang, C. G.;
   Yang, X. F.; Yao, Z. G.; Yu, Z. Q.; Zhang, S.; Zhu, G. Y.; Zhu, Q. Q.;
   Zhuang, H. L.; Zwart, A. N. M.
Bibcode: 2002NIMPA.488..209A
Altcode:
  The L3 detector at the CERN electron-positron collider, LEP, has been
  employed for the study of cosmic ray muons. The muon spectrometer
  of L3 consists of a set of high-precision drift chambers installed
  inside a magnet with a volume of about 1000m<SUP>3</SUP> and a field of
  0.5T. Muon momenta are measured with a resolution of a few percent at
  50GeV. The detector is located under 30m of overburden. A scintillator
  air shower array of 54m by 30m is installed on the roof of the surface
  hall above L3 in order to estimate the energy and the core position of
  the shower associated with a sample of detected muons. Thanks to the
  unique properties of the /L3+C detector, muon research topics relevant
  to various current problems in cosmic ray and particle astrophysics
  can be studied.

Title: Fast magnetosonic waves driven by gravitational waves
Authors: Papadopoulos, D.; Stergioulas, N.; Vlahos, L.; Kuijpers, J.
Bibcode: 2001A&A...377..701P
Altcode: 2001astro.ph..7043P
  The propagation of a gravitational wave (GW) through a magnetized
  plasma is considered. In particular, we study the excitation of
  fast magnetosonic waves (MSW) by a gravitational wave, using the
  linearized general-relativistic hydromagnetic equations. We derive the
  dispersion relation for the plasma, treating the gravitational wave
  as a perturbation in a Minkowski background space-time. We show that
  the presence of gravitational waves will drive magnetosonic waves in
  the plasma and discuss the potential astrophysical implications.

Title: A cellular automaton model for the magnetic activity in
    accretion discs
Authors: Pavlidou, V.; Kuijpers, J.; Vlahos, L.; Isliker, H.
Bibcode: 2001A&A...372..326P
Altcode:
  In this paper we attempt, for the first time, to simulate the magnetic
  activity of an accretion disc using a probabilistic cellular automaton
  model. Our model is based on three free parameters, the probabilities of
  spontaneous and stimulated generation of magnetic flux above the surface
  of the disc (S<SUB>0</SUB>, and, respectively, P), and the probability
  of diffusive disappearance of flux below the surface (D). The model
  describes a changing collection of flux tubes which stick out of the
  disc and are anchored inside the disc at their foot-points. Magnetic
  flux tubes transfer angular momentum outwards at a rate which is
  analytically estimated for each single loop. Our model monitors the
  dynamic evolution of both the distribution of magnetic loops and the
  mass transfer which results from angular momentum transport due to
  this distribution. The energy release due to magnetic flaring is also
  recorded as a function of time and exhibits temporal fluctuations with
  power spectra that depend on the assumed emission-profile of single
  flaring loops: (i) for instantaneous emission, the power-spectra
  are flat at low frequencies and turn over at high frequencies to a
  power-law with index -0.3; (ii) for emission-profiles in the form
  of one-sided exponentials, the power-spectra exhibit clear power-law
  behaviour with index -1.7. Fluctuations with a power law index between
  -1 and -1.7 are observed in many systems undergoing accretion. We found
  that our approach allows steady accretion in a disc by the action
  of coronal magnetic flux tubes alone. If we express the effective
  viscosity caused by coronal loops in the usual Shakura-Sunyaev alpha
  parameter of viscosity, we find values which are in good agreement
  with observed values.

Title: Equatorial Pulsar Winds
Authors: Kuijpers, Jan
Bibcode: 2001PASA...18..407K
Altcode:
  Atraditional problem in pulsar wind physics has been the nature of
  the pulsar wind. Ontheoretical grounds, the wind is expected to be
  dominated by Poynting flux associated with the outgoing magnetic
  field lines anchored on the polar caps of the rotating neutron star,
  while observations of the Crab Nebula demonstrate that the wind must
  be dominated by kinetic energy before the termination shock. Here we
  suggest a new approach to this old problem by studying the distributed
  currents rather than the singular sheet currents which have been
  the object of study in most work. We find that, at a distance well
  in between the light cylinder and the termination shock, current
  starvation sets in, and electric fields develop along the magnetic
  field lines which cause the current to dissipate and convert at least
  half of the Poynting flux into kinetic energy flux in a relatively
  thin shell. In the shell, at least half of the current closes across
  the magnetic field lines, the pitch of the spiralling magnetic field
  lines jumps downward strongly, and the outer pattern of magnetic field
  lines slips over the inner pattern.

Title: Flare Physics in Accretion Discs
Authors: Pavlidou, V.; Kuijpers, J.; Vlahos, L.; Isliker, H.
Bibcode: 1999ESASP.448..859P
Altcode: 1999mfsp.conf..859P; 1999ESPM....9..859P
  No abstract at ADS

Title: Magnetodipole Oven
Authors: Istomin, Ya. N.; Kuijpers, J.
Bibcode: 1998tx19.confE.247I
Altcode:
  We found that electromagnetic fields of magnetodipole radiation can
  penetrate to the conducting matter of the neutron star's crust and
  create there the electric currents and tangential magnetic field
  of high magnitude. The obtained solution has the form of surface of
  magnetic field discontinuous slowly propagating through the crust to
  the core. This model explains the phenomena of Anomalous X-ray pulsars
  and Magnetars.

Title: Het gelijk van Einstein. De zwaartekracht als weegschaal
    en telescoop.
Authors: Kuijpers, J.
Bibcode: 1998Zenit..25..196K
Altcode:
  No abstract at ADS

Title: The Coriolis Effect and the Origin of Prominences
Authors: Kuijpers, J.; Mestel, L.
Bibcode: 1998ESASP.417..247K
Altcode: 1998cesh.conf..247K
  No abstract at ADS

Title: A Solar Prominence Model
Authors: Kuijpers, Jan
Bibcode: 1997ApJ...489L.201K
Altcode: 1997astro.ph..9178K
  We propose a model for solar prominences based on converging flow
  observed in the chromosphere and photosphere. In contrast with
  existing models, we do not apply a shearing motion along the neutral
  line. Instead, we assume that bipolar loops approaching on different
  sides of the neutral line have a nonvanishing magnetic helicity of
  the same sign. In the converging flow the individual loops kink and
  develop a skew. For loops of the same helicity the skew is in the same
  sense. As a result the "chiral" symmetry of an aligned distribution of
  loops is broken, and the reconnecting loop system forms a filament with
  the observed magnetic orientation and anchoring of the barbs in regions
  of parasitic polarity. The filament consists of a number of individual
  strands of coaxial coronal electric currents, each of which is current
  neutralized. The filament material is suspended in dips in the magnetic
  field, and the transverse field direction coincides with that in the
  Kuperus-Raadu model. Above the filament a cavity forms with an overlying
  arcade consisting of the outer portions of the reconnected loops.

Title: Magnetic pumping in the cataclysmic variable AE Aquarii.
Authors: Kuijpers, J.; Fletcher, L.; Abada-Simon, M.; Horne, K. D.;
   Raadu, M. A.; Ramsay, G.; Steeghs, D.
Bibcode: 1997A&A...322..242K
Altcode:
  We propose that the radio outbursts of the cataclysmic variable
  AE Aqr are caused by eruptions of bubbles of fast particles from
  a magnetosphere surrounding the white dwarf. We investigate the
  acceleration process of magnetic pumping in the magnetosphere which
  is periodically driven both by the relative motion with the companion
  and with the infalling spray of gas at the spin frequency of the white
  dwarf. As the accretion rate is relatively low, the conversion of spin
  energy into acceleration (rather than heating) of electrons and protons
  can be efficient. The accelerated particles are trapped in the white
  dwarf magnetosphere until their total energy content becomes comparable
  to that of the trapping magnetic field structure and a MHD instability
  sets in. Synchrotron radiation is emitted in the expelled expanding
  plasmoid at radio and down to millimetric wavelengths. We find that
  there is sufficient energy transferred from the rotation energy of the
  rapidly-spinning white dwarf to fast particles by magnetic pumping to
  explain quiescent and flaring radio emissions.

Title: Are Coronal Mass Ejections Caused by Magnetic Pumping?
Authors: Kuijpers, Jan; Fletcher, Lyndsay
Bibcode: 1996SoPh..169..415K
Altcode:
  Magnetic pumping in the solar corona is revisited. We derive conditions
  under which magnetic pumping can be the cause of heating of loops
  rather than of particle acceleration. Candidate sources for such a
  process are coronal mass ejections (CMEs). Large loops are susceptible
  to heating primarily of protons by magnetic compressions with periods
  between 50 and 5000 s, the observed spectrum of the photospheric
  driver. Efficient heating by pumping occurs since in these large loops
  the density is low enough that the proton-proton collision time is
  comparable to the periods of the external compressions. We suggest
  that CMEs may be pressure-driven explosions of large-beta loops
  caused by magnetic pumping, in contrast to current-driven `flares'
  in low-beta environments.

Title: Radiation-driven envelopes around magnetic white
    dwarfs. Radiation-driven diskons.
Authors: Zheleznyakov, V. V.; Serber, A. V.; Kuijpers, J.
Bibcode: 1996A&A...308..465Z
Altcode:
  We investigate the formation of a plasma envelope in the magnetosphere
  of a hot white dwarf by cyclotron radiation pressure. The radiation
  pressure distribution (both in the continuum and in the cyclotron line)
  is derived for an optically thin, dipolar magnetosphere of an isolated,
  non-rotating star emitting blackbody radiation. For an isothermal,
  fully ionized, pure hydrogen plasma the hydrostatic solution consists
  of a closed plasma shell accumulated in a potential well near the
  equilibrium surface, where radiation pressure cancels gravity, and an
  equatorial disk inside this surface. The presence of a finite optical
  depth leads to a temporal variation of the plasma envelope and of the
  observed radiation. We apply these results to the strongly magnetized
  white dwarf GD229, which is a candidate for such a radiation-driven
  envelope or "diskon". The deep unidentified 2000-3000. in its UV
  spectrum is explained as the result of cyclotron scattering in optically
  thick gyroresonant layers around the star. We predict a temporal and
  spectral variability of this feature with a characteristic time of
  &gt;=1hr due to non-stationary plasma motions in the envelope.

Title: Triggering the radio emission from AE Aqr:
Authors: Steeghs, D.; Kuijpers, J.; Fletcher, L.; et al.
Bibcode: 1996ASSL..208..167S
Altcode: 1996IAUCo.158..167S; 1996cvro.coll..167S
  No abstract at ADS

Title: Radio emission from polar caps in pulsars
Authors: Kuijpers, J.; Volwerk, M.
Bibcode: 1996ASPC..105..181K
Altcode: 1996IAUCo.160..181K; 1996ppp..conf..181K
  No abstract at ADS

Title: Radio Emission from AE Aquarii
Authors: Abada-Simon, M.; Bastian, T. S.; Fletcher, L.; Horne, K.;
   Kuijpers, J.; Steeghs, D.; Bookbinder, J. A.
Bibcode: 1996ASPC...93..182A
Altcode: 1996ress.conf..182A
  No abstract at ADS

Title: Particle Acceleration
Authors: Kuijpers, J.
Bibcode: 1996LNP...468..101K
Altcode: 1996plas.conf..101K
  It is the purpose of this series of lectures to give an overview of our
  understanding of (electromagnetic) particle acceleration processes in
  astrophysics. For each process I emphasize the basic physics and point
  out differences and correspondences with other mechanisms. Remaining
  problems are summarized with references to the recent literature. For
  instructive reasons I first discuss a number of fundamental aspects
  which are common to several acceleration processes. Thereafter I have
  grouped the various processes for particle accelaration into three
  chapters according to their underlying physical mechanism: plasma
  turbulence, shock waves, and direct electric fields.

Title: Cosmic magnetic fields
Authors: Kuijpers, Jan
Bibcode: 1995PhyB..211..306K
Altcode:
  After a summary of the observations of cosmic magnetic fields, I
  briefly discuss the status of dynamos, the use of electric circuits,
  the physics of magnetic explosions, the role of magnetic tension and
  our strongest magnet known, the radio pulsar. Finally I mention a few
  problem areas which may show a breakthrough in the near future.

Title: Flares in Accretion Disks
Authors: Kuijpers, J.
Bibcode: 1995LNP...444..135K
Altcode: 1995cmer.conf..135K
  Present understanding of solar flares suggests that violent flare
  phenomena are common place in coronae of accretion disks. In particular
  near magnetized compact objects accretion can be modified by repeated
  magnetic energy storage and release. Further also in the absence of a
  central magnetosphere, such as around galactic and extragalactic black
  holes, magnetic flaring activity is possible in a corona on both sides
  of the disk.

Title: A magnetic explanation for the rapid burster.
Authors: Kuijpers, J.; Kuperus, M.
Bibcode: 1994A&A...286..491K
Altcode:
  The main observations of Type II bursts in the low-mass X-ray binary
  MXB 1730-335 (the Rapid Burster) can be understood if the neutron star's
  magnetic field is strong (7 x 10^11^ - 2 x 10^12^ gauss at the surface)
  and rotationally symmetric around the axis of a steadily accreting
  disk. We show that a Keplerian disk of matter develops inside the
  pressure balance radius where it is compressed into a very thin disk
  by the external magnetic field. At the inner edge of the disk a ring
  of matter is suspended in the stellar magnetic field and corotates
  with the star. During quiescence the disk penetrates more and more
  into the magnetosphere, the ring accumulates gas and shifts to lower
  altitudes. The stellar field sets a maximum to the amount of supported
  gas. As soon as the threshold is passed an ideal mhd instability occurs,
  the matter ring falls onto the surface and triggers a violent burst of
  accretion. As the stellar field relaxes outward accretion onto the star
  continues to be enhanced until a new magnetic equilibrium is attained,
  the burst ends and a smaller ring is left at higher altitudes. As the
  (steady) external accretion continues the ring load increases again
  and moves inward until the threshold is reached and the sequence
  repeats. Such a bursting behaviour only occurs if the star is an
  aligned rotator.

Title: A magnetic explanation for the rapid burster
Authors: Kuijpers, J.; Kuperus, M.
Bibcode: 1994SSRv...68..333K
Altcode:
  The observations of X-ray Type II bursts from the low-mass X-ray
  binary MXB 1730-335 can be explained by a particular form of magnetic
  gating in the presence of steady external accretion. The requirements
  are a strong magnetic field of the neutron star (7×10<SUP>11</SUP>
  2×10<SUP>12</SUP> gauss at the surface), rotational symmetry and
  alignment of the field axis with the axis of a steadily accreting disk
  to within 6°.

Title: Pair creation in double layers
Authors: Volwerk, Martin; Kuijpers, J.
Bibcode: 1994SSRv...68..363V
Altcode:
  Pair creation in relativistic double layers in shown to have
  consequences for the charge density in the double layer and the current
  flowing through it.

Title: Foreword
Authors: van den Oord, Bert; Kuijpers, Jan; Kuperus, Max; Benz, A. O.;
   Brown, J. C.; Einaudi, G.; Kuperus, M.; Raadu, M. A.; Trottet, G.;
   van den Oord, G. H. J.; Vlahos, L.; Zheleznyakov, V. V.; Wijburg,
   Marion; Fletcher, Lyndsay; Volwerk, Martin
Bibcode: 1994SSRv...68D..17V
Altcode:
  No abstract at ADS

Title: Strong Double Layers, Existence Criteria, and Annihilation:
    an Application to Solar Flares
Authors: Volwerk, Martin; Kuijpers, Jan
Bibcode: 1994ApJS...90..589V
Altcode: 1994IAUCo.142..589V
  We present some conditions for the stability of a strong double
  layer in a warm, current-carrying plasma, which can be extended into
  the relativistic regime. We apply a model for plama heating by the
  electron beam emitted from the double layer and show that this leads
  to a finite life time to the double layer. We also show that the radio
  emission accompanying this process can well describe the observed
  phenomena in Type I radio bursts using a direct emission mechanism,
  not involving Langmuir waves.

Title: Magnetic flares near accreting black holes
Authors: Volwerk, M.; van Oss, R. F.; Kuijpers, J.
Bibcode: 1993A&A...270..265V
Altcode:
  The present treatment of magnetic flaring interactions between a
  black hole and an ionized accretion disk assumes that magnetic fields
  created in the disk, and extending into a force-free corona, will be
  transported onto the black hole time-horizon by the accreting plasma;
  magnetic links between disk and horizon would then occur. An equilibrium
  condition on the field structure of the connection is found not to be
  generally satisfied. It is concluded that these magnetic connections
  will release their free energy during flares, and that the form this
  can take, as a sequence of magnetic explosions, can be a measurable
  fraction of disk luminosity for stellar-mass black hole candidates.

Title: Elastiekjes, magneten en vuurwerk.
Authors: Kuijpers, J.
Bibcode: 1993Zenit..20..125K
Altcode:
  No abstract at ADS

Title: Book reviews
Authors: Pallottino, G. V.; Heintze, J. R. W.; van Delden, A. J.;
   Marov, Mikhail Ya.; Kuijpers, J. M. E.; Spoelstra, T. A. Th.; Voigt,
   H. H.; van Gent, R. H.; Thé, P. S.; Henrichs, Huib; Icke, V.
Bibcode: 1993SSRv...63..191P
Altcode:
  No abstract at ADS

Title: Book Review: Transition radiation and transition scattering /
    Adam Hilger, 1990
Authors: Kuijpers, J.
Bibcode: 1993SSRv...63..195K
Altcode: 1993SSRv...63..195G
  No abstract at ADS

Title: Pulsar core emission and double layers
Authors: Volwerk, M.; Kuijpers, J.
Bibcode: 1993dlon.conf..459V
Altcode:
  No abstract at ADS

Title: Book-Review - Physical Processes in Hot Cosmic Plasma
Authors: Brinkmann, W.; Fabian, A. C.; Giovannelli, F.; Kuijpers,
   J. M. E.
Bibcode: 1993SSRv...63..193B
Altcode:
  No abstract at ADS

Title: A magnetic flare model for X-ray variability in AGN.
Authors: de Vries, M.; Kuijpers, J.
Bibcode: 1992A&A...266...77D
Altcode:
  The power spectra of X-ray light curves of active galactic nuclei
  (AGN) observed with EXOSAT, show approximately the same 1/v power
  law dependence. To explain the X-ray variability we propose a flare
  model based on recurrent explosive release of stored magnetic energy
  in coronae of accretion disks in AGN. Based on the virial theorem
  we develop an analytical model for the power released in magnetic
  flares in a radiation pressure dominated accretion disk corona. A major
  difference exists with the solar case: beams of relativistic electrons
  produced by the flare in the corona, loose all their energy by inverse
  Compton scattering on UV disk photons before being able to reach the
  disk. These Compton losses determine the X-ray variability. It is shown
  how the dependence of the flare characteristics on the distance to the
  central object provides the required range in time-scales and power to
  reproduce the observed power spectra. Finally we present a worked out
  model based on the van Tend- Kuperus solar flare model. Our results
  on the predicted power spectra are however independent of the assumed
  applicability of the lather model.

Title: Magnetic flares near black holes.
Authors: Volwerk, M.; Kuijpers, J.; van Oss, R.
Bibcode: 1992ASIC..377..537V
Altcode: 1992xrb..work..537V
  No abstract at ADS

Title: Physics of Flares in Stars and Accretion Disks
Authors: Kuijpers, J.
Bibcode: 1992ASIC..373..535K
Altcode: 1992sla..conf..535K
  No abstract at ADS

Title: Book reviews
Authors: Hayakawa, S.; Kuijpers, J.; Kleczek, J.; Valnicek, Boris;
   Kresak, L.; de Ruiter, H. R.
Bibcode: 1991SSRv...57..189H
Altcode:
  No abstract at ADS

Title: Flaring interactions between accretion disk and neutron star
    magnetosphere.
Authors: Aly, J. J.; Kuijpers, J.
Bibcode: 1990A&A...227..473A
Altcode:
  The effect of magnetic reconnections between the magnetosphere of a
  neutron star and the accretion disk is considered using a model of
  a neutron-star/disk system, which assumes the existence of magnetic
  'loops' anchored in the disk and extending into a corona on both
  sides of the disk. It is shown that these magnetic links are efficient
  transmitters of angular momentum. At the disk plane, the linked field
  is forced to rotate with near-Keplerian velocity, while it corotates
  with the star at the other end. The magnetic energy is stored in the
  sheared and expanding field link, which is released upon a transition
  to a lower energy state again caused by reconnection. This process
  leads to a release of flaring energy in the magnetosphere and to
  the transport of angular momentum between the disk and the star. It
  is proposed that these magnetic flares might be an explanation for
  quasi-periodic oscillations.

Title: A Nonsteady Reconnection Model for Solar Prominences.
Authors: Kuijpers, J.
Bibcode: 1990ppsa.conf..227K
Altcode:
  No abstract at ADS

Title: Coherent Radiation from Electrostatic Double Layers.
Authors: Kuijpers, J.
Bibcode: 1990ppsa.conf...17K
Altcode:
  No abstract at ADS

Title: Magnetic Flares in Close Binaries
Authors: Kuijpers, J.
Bibcode: 1990ASIC..319..761K
Altcode: 1990acb..proc..761K
  No abstract at ADS

Title: Coherent Radiation from Electrostatic Double Layers
Authors: Kuijpers, Jan
Bibcode: 1990IAUS..142..365K
Altcode:
  The efficiency of two coherent radiation processes - antenna radiation
  and a maser process - is studied. Both processes are found capable
  of operating in electrostatic double layers (DLs) to produce intense
  and narrow-band emission. Antenna radiation occurs if the dimensions
  of the double layer are smaller than the wavelength of the emitted
  radiation. The maser requires an amplification length inside the
  double layer much larger than the emitted wavelength, and can lead
  to observable emission in astrophysical circumstances. The growth is
  exponential and the rate depends only on the electric field energy
  density of the DL. Since the latter is externally controlled by the
  electric circuit, it is a constant for the emission process so as
  to constitute a true maser. The maximum brightness temperature is of
  the order of 10 exp 25 K. Masing radiation from electrostatic DLs is
  therefore a candidate for some of the observed intense narrow-band
  cosmic radio emission.

Title: A magnetic flare model for X-ray variability in AGN.
Authors: de Vries, Mark; Kuijpers, Jan
Bibcode: 1989ESASP.296.1069D
Altcode: 1989ttxa.symp.1069D
  The authors develop a model to explain the observed, approximately 1/f,
  power spectrum of the X-ray variability in low-luminosity Seyferts. The
  proposed model involves a current carrying mass filament in the corona
  of an accretion disk. Using arguments similar to the ones put forward
  for solar flares, the authors estimate the amount of magnetic energy
  which can be stored inside the tube. They determine the kinetic energy
  of particle beams which result from this flare process. Inverse Compton
  loss times and emitted power from the beams are calculated and they
  seem to fit the observations very well. Possible means of verification
  of the model are indicated.

Title: Radio Emission from Stellar Flares
Authors: Kuijpers, Jan
Bibcode: 1989SoPh..121..163K
Altcode: 1989IAUCo.104..163K
  An overview is given of the observations of stellar radio `flares',
  defined as radio emission which is both variable in time and created
  by explosive releases of magnetic energy. The main sources of such
  flares are late-type Main-Sequence stars, classic close binaries,
  X-ray binaries, and pre-Main-Sequence stars.

Title: A combined radio and X-ray observation of Algol.
Authors: van den Oord, G. H. J.; Kuijpers, J.; White, N. E.; van der
   Hulst, J. M.; Culhane, J. L.
Bibcode: 1989A&A...209..296V
Altcode:
  The detection of Algol (Beta Per) at 1.4 GHz is reported. The eclipsing
  phase of Algol has been observed in radio and at X-ray energies. The
  radio emission is explained as synchrotron radiation from electrons
  with energies of about 1 MeV. The magnetic field strength is of the
  order of tens of Gauss. The radio and X-ray emission are cospatial but
  the energy in the radio component is 1,000,000 times smaller than that
  of the X-ray component. The simultaneous observation indicates that
  an energetic particle component can be present in a quiescent X-ray
  emitting corona.

Title: MHD waves from inhomogeneous accretion in T Tauri stellar
    magnetospheres
Authors: Scheurwater, R.; Kuijpers, J.
Bibcode: 1988A&A...190..178S
Altcode:
  The authors consider the radiation of MHD-waves when a
  protostellar plasma cloud falls along an ambient magnetic
  field onto the surface of a T Tauri star. It is shown that the
  excitation mechanism is efficient in the frequency interval
  0 &lt; ω ⪉ 4 v<SUB>c</SUB>/r<SUB>c</SUB> where the infall
  velocity v<SUB>c</SUB> of the cloud is taken to be subalfvénic
  and r<SUB>c</SUB> is the radius of the cloud. The efficiency
  of wave-excitation is calculated and turns out to be of order 0.1
  (ρ<SUB>c</SUB>/ρ<SUB>0</SUB>)(v<SUB>c</SUB>/c<SUB>A</SUB>)<SUP>3</SUP>
  for the Alfvén mode and of order 1.8
  (ρ<SUB>c</SUB>/ρ<SUB>0</SUB>)(v<SUB>c</SUB>/c<SUB>A</SUB>)<SUP>7</SUP>
  for the fast mode (c<SUB>A</SUB> is the Alfvén speed, ρ<SUB>c</SUB>
  is the mass density inside the cloud and ρ<SUB>0</SUB> that of the
  ambient atmosphere).

Title: On the Controversy Concerning Turbulent Bremsstrahlung
Authors: Melrose, D. B.; Kuijpers, J.
Bibcode: 1987ApJ...323..338M
Altcode:
  It is shown that the derivation of a nonzero growth rate for
  turbulent bremsstrahlung involves an incomplete summation of the
  nonlinear responses. When the classically correct expression is used,
  the growth rate is identically zero. Next the authors show that the
  radiative correction to the resonant emission of ion sound waves in the
  presence of nonresonant Langmuir waves is derived explicitly. Finally,
  they reply to criticisms by Nambu (1986) of an earlier paper and show
  that the inclusion of a background magnetic field gives a zero growth
  rate for this proposed kind of turbulent bremsstrahlung.

Title: Book Review: Instabilities in space and laboratory plasmas. /
    CUP, 1986.
Authors: Kuijpers, J.
Bibcode: 1987SSRv...45..408K
Altcode: 1987SSRv...45..408M
  No abstract at ADS

Title: A High-Energy Solar Flare Burst Complex and the Physical
    Properties of its Source Region
Authors: de Jager, Cornelis; Kuijpers, Jan; Correia, Emilia; Kaufmann,
   Pierre
Bibcode: 1987SoPh..110..317D
Altcode:
  We discuss a solar flare microwave burst complex, which included a
  major structure consisting of some 13 spikes of 60 ms FWHM each,
  observed 21 May, 1984 at 90 GHz (3 mm). It was associated with a
  simultaneous very hard X-ray burst complex. We suggest that the
  individual spikes of both bursts were caused by the same electron
  population: the X-bursts by their bremsstrahlung, and the microwave
  bursts by their gyrosynchrotron emission. This latter conclusion
  is based on the evidence that the radio turnover frequency was ≤
  150 GHz. It follows that the emission sources were characterized
  by an electron density of about 10<SUP>11</SUP> cm<SUP>−3</SUP>,
  a temperature of 5 × 10<SUP>8</SUP> K and a magnetic field of about
  1400-2000 G. They had a size of about 350 km; if the energy release is
  caused by reconnection the sources of primary instability could have
  been smaller and in the form of thin sheets with reconnection speed at
  a fraction of the Alfvén velocity and burst-like energy injections
  of ≈ 10<SUP>27</SUP> erg during about 50 ms each. The energized
  plasma knots lost their injection energy by saturated convective flux
  (collisionless conduction) in about 30 ms.

Title: A high energy solar flare burst complex and the physical
    properties of its source region
Authors: De Jager, C.; Kuijpers, J.; Correia, E.; Kaufmann, P.
Bibcode: 1986cospar........D
Altcode:
  A solar flare microwave burst complex, which exhibited a major structure
  consisting of some 13 spikes of 60 ms FWHM each, observed 21 May 1984
  at 90 GHz (3 mn) is discussed. It was associated with a simultaneous
  very hard X-ray burst complex. A possible explanation in which the
  individual spikes of both bursts were caused by the same electron
  population is developed: the X-ray bursts by their bremsstrahlung, and
  the microwave bursts by their gyro-synchrotron emission. This latter
  explanation is based on the assumption that the radio turnover frequency
  is less than 150 GHz. The emission sources were characterized by an
  electron density of about 10 to the 11th power/cu cm, a temperature
  of 5 x 10 to the 8th power K and magnetic field of about 1400 to 2000
  G. They had a size of about 350 km; if the energy release is caused
  by reconnection the sources of primary instability could have been
  smaller and in the form of thin sheets with reconnection speed at
  a fraction of the Alfven velocity and burst-like energy injections
  of 10 to the 27th power erg during about 50 ms each. The energized
  plasma knots lost their injection energy by saturated convective flux
  (collisionless conduction) in about 30 ms.

Title: Bombardment solutions to the "soft X-ray puzzle" in radial
    white dwarf accretion.
Authors: Thompson, A. M.; Brown, J. C.; Kuijpers, J.
Bibcode: 1986A&A...159..202T
Altcode:
  The problem of the observed low ratio of hard to soft X-rays in
  accreting white dwarfs, with low accretion rate (e.g. AM Her), is
  discussed in terms of models where the accreting matter is treated as
  a nonthermal stream bombarding a static atmosphere cooled by optically
  thin radiation (Kuijpers and Pringle, 1982). It is shown that the
  proton collisional mean free path used by Kuijpers and Pringle (1982)
  was inappropriate for the inferred temperature regime and that when
  the correct expression is used the global mean temperature of a steady
  state bombardment solution is much lower (about 10 to the 5 K) and much
  closer to observations. It is seen that no steady state solution is
  possible without invoking some other kind of energy transport mechanism;
  such bombardment models cannot explain the 'soft X-ray puzzle'. The
  shock solution of Frank and King (1984) - and its failure to solve
  the puzzle - are discussed.

Title: An EXOSAT Observation of Quiescent and Flare Coronal X-Ray
    Emission from Algol
Authors: White, N. E.; Culhane, J. L.; Parmar, A. N.; Kellett, B. J.;
   Kahn, S.; van den Oord, G. H. J.; Kuijpers, J.
Bibcode: 1986ApJ...301..262W
Altcode:
  X-ray emission from the Algol system is believed to originate in a
  corona associated with the K star. The authors have used the EXOSAT
  Observatory to make a 35 hr continuous observation centered on the
  occultation of the K star by the B star primary. The spectrum of
  the quiescent emission in the 1 - 10 keV band gives a temperature of
  2.5×10<SUP>7</SUP>K. This spectrum, extrapolated to lower energies,
  can account for more than 80% of the observed count rate. No obvious
  X-ray eclipse was seen. An X-ray flare was detected with a rise time
  of ≡1700 s and an exponential decay of ≡7000 s. The 0.1 - 10 keV
  peak luminosity was 1.4×10<SUP>31</SUP>ergs s<SUP>-1</SUP>. The peak
  temperature was 6×10<SUP>7</SUP>K, with an iron K line confirming
  the thermal character of the emission.

Title: Solar VLBI.
Authors: Tapping, K. F.; Kuijpers, J.
Bibcode: 1986NASCP2449..211T
Altcode: 1986rfsf.nasa..211T
  In April, 1981, radio telescopes at Dwingeloo (The Netherlands)
  and Onsala (Sweden) were used as a long-baseline interferometer at a
  wavelength of 18 cm. The baseline of 619 km gave a spatial resolution on
  the Sun of about 45 km. The major problems of Solar Very Long Baseline
  Interferometry are discussed.

Title: Book-Review - Cold Plasma Waves
Authors: Booker, H. G.; Kuijpers, J.
Bibcode: 1985SSRv...41..402B
Altcode:
  No abstract at ADS

Title: Interpretation of unpolarized radio emission from RS CVn stars.
Authors: Kuijpers, J.; van der Hulst, J. M.
Bibcode: 1985A&A...149..343K
Altcode:
  The authors investigate the emission process and the energy budget
  of radio flares in RS CVn stars by applying various mechanisms to
  the close binary σ<SUP>2</SUP>CrB (HD 146361) of RS CVn type. Radio
  emission from this system observed with the WSRT at 21 cm is explained
  as synchrotron emission from electrons with Lorentz factors 3.5-3.1 in
  magnetic fields of strength 27 - 35 G. The energy source of the radio
  emitting electrons and of the previously observed X-ray gas is studied;
  the authors show that a solar-like filament flare forms an attractive
  mechanism to explain the observed energy release.

Title: Nonexistence of two forms of turbulent bremsstrahlung
Authors: Kuijpers, J.; Melrose, D. B.
Bibcode: 1985ApJ...294...28K
Altcode:
  It is shown that the forms of turbulent bremsstrahlung proposed by
  Tsytovich, Stenflo, and Wilhelmsson (1975) and by Nambu (1981) do
  not exist. The proposed mechanisms involve upconversion of ion sound
  turbulence into Langmuir turbulence, with the ion sound waves being
  emitted and absorbed resonantly and the Langmuir waves being emitted
  and absorbed nonresonantly. It is pointed out that a symmetry implicit
  in a standard QED treatment implies that there is another contribution
  to turbulent bremsstrahlung in addition to that calculated by Tsytovich,
  Stenflo, and Wilhelmsson and that the two contributions cancel exactly,
  leading to the null result. Nambu made an approximation inconsistently,
  and when this approximation is not made, two terms in his analytic
  treatment cancel exactly. It is argued that turbulent bremsstrahlung
  is related to a radiative correction in which the resonant emission
  of ion sound turbulence is modified by the nonresonant emission and
  absorption of Langmuir waves. Physically the nonexistence of turbulent
  bremsstrahlung is interpreted as being due to each emission of a
  Langmuir quantum being associated with an absorption of an identical
  Langmuir quantum so that the Langmuir turbulence is unchanged. Proposed
  astrophysical applications of turbulent bremsstrahlung need to be
  reconsidered.

Title: Bombardment Models of White Dwarf Accretion Columns
Authors: Thompson, A. M.; Brown, J. C.; Kuijpers, J.
Bibcode: 1985ASSL..116...43T
Altcode: 1985rst..conf...43T
  The problem of the observed low ratio of hard to soft X-rays in
  accreting white dwarfs, with low accretion rates, (e.g. AM Her) is
  discussed in terms of models where the accreting matter is treated as
  a non-thermal stream bombarding a static atmosphere cooled by optically
  thin radiation (Kuijpers &amp; Pringle, 1982).

Title: An EXOSAT Observation of the Morphology of the Coronal X-Ray
    Emission from Algol
Authors: White, N. E.; Culhane, J. L.; Parmar, A. N.; Kellett, B.;
   Kahn, S.; van den Oord, G. H. J.; Kuijpers, J.
Bibcode: 1985SSRv...40...25W
Altcode:
  The X-ray emission from Algol is thought to originate in a corona
  associated with the K star in this system. We report the results of a 35
  hr continuous EXOSAT observation through secondary optical eclipse that
  was designed to measure the structure of the corona. No obvious X-ray
  eclipse was seen. The spectrum measured by the ME gives a temperature of
  2.5 × 10<SUP>7</SUP> K, consistent with the hard component previously
  seen by the Einstein SSS. The soft component previously reported by
  the SSS would only contribute at most 25% to the count rate seen in
  the LE (used with Al/P). The lack of a hard X-ray eclipse indicates the
  dimensions of the higher temperature emission region to be comparable
  to or greater than the size of the K star. An X-ray flare was detected
  with a peak luminosity of 1.4 × 10<SUP>31</SUP> erg s<SUP>-1</SUP>
  and a total duration of 8 hours. The peak temperature was 5.0 keV with
  an emission measure of 9.4 × 10<SUP>53</SUP> cm<SUP>-3</SUP>. The
  thermal nature of the flare is confirmed by the detection of an iron
  line with an EW of ∼2 keV. By equating the observed decay time of
  the flare to a known cooling law gives a dimension for the flaring
  loop of ∼0.3 stellar radii. This is much smaller than the dimensions
  of the hard component inferred from the lack of an eclipse. It seems
  probable that the flare occurred in one of the loops responsible for
  the lower temperature component seen by the SSS.

Title: The physics of active stellar systems.
Authors: Kuijpers, J.
Bibcode: 1985NTNA...51...21K
Altcode:
  No abstract at ADS

Title: Radio Observable Processes in Stars (Invited Paper)
Authors: Kuijpers, J.
Bibcode: 1985ASSL..116....3K
Altcode: 1985rst..conf....3K
  The most important physical processes in the atmospheres of (noncompact)
  stars that can be studied fruitfully with observations in the radio
  continuum are reviewed. The emission mechanisms are free-free and
  gyrosynchrotron radiation, (inverse) Compton scattered, and various
  kinds of plasma radiation. The free-free emission in stellar winds
  where observations of time variations are important for the study of
  instabilities and relaxation oscillations is considered. The main part
  of the paper concerns magnetic activity, and in particular stellar
  flares. Mostly from a theoretical point of view, the problems of the
  density of the flare plasma, the flare energy, dMe flare stars, detached
  (RS CVn stars) and semidetached (Algols) close binaries, are considered,
  together with the role of duplicity, magnetic interactions and mass
  transfer, T Tauri stars, and particle acceleration in shocks and in
  the unipolar inductor. Finally, the various kinds of plasma radiation
  are reviewed, and the importance of establishing the brightness
  temperature of flares with VLBI, and of observing the nature and degree
  of polarization to find out the flare plasma physics, is pointed out.

Title: Resonant parts of nonlinear response tensors
Authors: Melrose, D. B.; Kuijpers, J.
Bibcode: 1984JPlPh..32..239M
Altcode:
  It is pointed out that ambiguities arise in taking the resonant parts
  of nonlinear response tensors. A prescription is proposed and used
  to evaluate the resonant parts explicitly in terms of a covariant
  and gauge invariant formalism. Symmetry properties of the resonant
  parts are identified. The prescription used can be justified by
  analogy with a calculation based on QED where no ambiguity arises;
  it is also justified directly by classical arguments. In some standard
  treatments of nonlinear damping processes a necessary symmetry is not
  imposed. When this symmetry is imposed, the relations derived here
  imply that turbulent bremsstrahlung, as defined by Tsytovich et al.,
  does not exist.

Title: Book reviews
Authors: Kuijpers, Jan; Kleczek, Josip; Lamers, H. J. G. L. M.; Kruit,
   P. C. V. D.; Kuperus, M.; Knott, K.
Bibcode: 1984SSRv...38..385K
Altcode:
  No abstract at ADS

Title: Book reviews
Authors: Ooms, O.; van der Woerd, Hans; Lamers, Henny J. G. L. M.;
   Kleczek, Josip; Kovalevsky, J.; Gathier, R.; Jarzebowski, T.; Swings,
   J. P.; van der Hucht, K. A.; Namba, O.; Mewe, R.; Lynden-Bell,
   D.; Kuijpers, Jan; van der Klis, M.; de Hoop, D.; Wittenberg, H.;
   Iwanowska, W.; Thé, P. S.; Schrijver, J.; Pottasch, S. R.
Bibcode: 1984SSRv...37..399O
Altcode:
  No abstract at ADS

Title: Diffusion of high energy electrons in the solar corona
Authors: Achterberg, A.; Kuijpers, J.
Bibcode: 1984A&A...130..111A
Altcode:
  A theoretical mechanism explaining the soft X-ray halo observed around
  the site of solar flares is proposed on the basis of an analytical
  investigation of anomalous diffusion of high-energy electrons by
  turbulent waves and magnetic irregularities. General expressions are
  derived and applied to the conditions prevalent in the solar corona,
  and the SMM (HXIS) and Culgoora radio observations of the flare of
  May 21-22, 1980, reported by Zvestka et al. (1982) are summarized and
  analyzed in the light of the analytical results. The X-ray halo can
  be explained by electron escape from the flaring loop via anomalous
  diffusion if electron energy is greater than about 100 keV, density
  is 10 to the 10th/cu cm or less, and the magnetic disturbance has
  (delta B)/B = a few percent.

Title: Book-Review - Astrophysical Jets
Authors: Ferrari, A.; Pacholczyk, A. G.; Kuijpers, J.
Bibcode: 1984SSRv...38..385F
Altcode:
  No abstract at ADS

Title: Book-Review - Highlights of Astronomy V.6
Authors: West, R. M.; Kuijpers, J.
Bibcode: 1984SSRv...37..404W
Altcode:
  No abstract at ADS

Title: Radial white dwarf accretion.
Authors: Kuijpers, J.; Pringle, J. E.
Bibcode: 1984PhST....7..120K
Altcode: 1984PhyS....7..120K
  The authors discuss radial accretion flow onto white dwarfs for which
  cyclotron emission is insignificant. It is shown that a stationary
  bombardment solution exists for not too large accretion rates in which
  the accretion energy is transferred to the target atmosphere within one
  collisional mean free path and then radiated at much lower temperatures
  than in the shock model.

Title: Book reviews
Authors: Namba, O.; Kuijpers, Jan; De Loore, C.; Roody, R. M.;
   Marlborough, J. M.; Rasool, S. I.; Kovalesky, J.; van der Kruit, P. C.;
   Kleczek, J.; de Jager, C.; Lewis, A.; Hovenier, J. W.; Grewing, M.
Bibcode: 1983SSRv...35..293N
Altcode:
  No abstract at ADS

Title: VLBI of solar flares
Authors: Tapping, K. F.; Kuijpers, J.; Kaastra, J. S.; van Nieuwkoop,
   J.; Graham, D.; Slottje, C.
Bibcode: 1983A&A...122..177T
Altcode:
  From April 28 to May 3, 1981, a VLBI experiment was carried out
  to observe small spatial scales in the initial energy release
  in solar flares. The 25 m radio telescope at Onsala (Sweden) and
  Dwingeloo (Netherlands) were used; the observing wavelength was 18
  cm. Simultaneous observations were made using the Westerbork Synthesis
  Radio Telescope at a wavelength of 6 cm. The VLBI baseline was 619
  km. During the observing period, three weak outbursts were observed,
  none yielding any strong correlated signals. However, the statistical
  behaviour of the correlator output over the range of delay channels
  shows significant indications of a correlated signal having a signal
  to noise ratio of order unity, during the impulsive spikes preceding
  the main phase of the event.

Title: Book-Review - Gravity Particles and Astrophysics
Authors: Wesson, P. S.; Kuijpers, J.
Bibcode: 1983SSRv...35..293W
Altcode:
  No abstract at ADS

Title: Very long baseline interferometry of solar flares
Authors: Kuijpers, J.; Tapping, K. F.; Graham, D.
Bibcode: 1983ASSL..102..339K
Altcode: 1983ards.proc..339K; 1983IAUCo..71..339K
  An experimental VLBI search for the occurrence of subarcsecond
  microwave emission centers as tracers of the initial energy release in
  solar flares is discussed. The observations extended over the period
  April 28 to May 3, 1981, during which period three weak outbursts
  occurred. No large correlations were observed, but a strong indication
  of an unresolved source with a signal to noise ratio of order unity
  was found during the impulsive bursts preceding the main phase of
  one event. During the impulsive bursts the spread in number of the
  channel which showed the maximum correlation amplitude was reduced
  significantly below the value for random behavior. A clear reduction
  in the amount of scatter from the expectation value during impulsive
  bursts is shown. The derived brightness temperature is of the order 10
  to the 12th K; the probable error box for the source position is shown.

Title: Comments on radial white dwarf accretion
Authors: Kuijpers, J.; Pringle, J. E.
Bibcode: 1982A&A...114L...4K
Altcode:
  The present study of radial accretion flow onto white dwarfs for which
  cyclotron emission is insignificant has ascertained that conduction
  cannot be the dominant energy loss mechanism if a stationary, standoff
  shock exists above the stellar surface. It is inferred that, in such
  cases, an abundance of hard X-rays is emitted. By analogy with solar
  coronal loop models, however, conduction may lead to stellar material
  evaporation and subsequent enhanced bremsstrahlung losses. Conduction
  may therefore influence the stability and global behavior of the
  post-shock region. It is demonstrated that there exists a stationary
  bombardment solution for moderate accretion rates in which the accretion
  energy is transferred to the target atmosphere within one collisional
  mean free path, and then radiated at much lower temperatures than
  in the shock model. A nonstationary model without standoff shock is
  also proposed.

Title: Runaway acceleration in a radio flare
Authors: Kuijpers, J.; van der Post, P.; Slottje, C.
Bibcode: 1981A&A...103..331K
Altcode:
  Radio observations of a solar flare are explained by induced electric
  fields in several small regions within a flaring flux tube. In each
  acceleration region runaway electrons are produced which lead to
  a pulsed production of high-frequency plasma waves. The model is
  used for an accurate determination of the physical conditions in the
  flare. During the runaway process an essential fraction of the runaway
  energy is put into plasma waves. The required electric field strength
  is of order E/E<SUB>c</SUB> approximately equal to 0.1 (E<SUB>c</SUB>
  is twice the Dreicer field) and the ratio of electron cyclotron to
  plasma frequency is of order unity or larger.

Title: Collisionless perpendicular shocks - Applications to solar
    type II radio bursts and the Antares /alpha Sco/ radio emission
Authors: Klinkhamer, F. R.; Kuijpers, J.
Bibcode: 1981A&A...100..291K
Altcode:
  A model of a collisionless perpendicular shock is proposed based
  on (1) local marginal stability of ion-acoustic waves and (2) ion
  heating in supercritical shocks by a beam of reflected ions behind
  the shock proper. The mean turbulence energy density in the shock is
  calculated. Type II radio bursts of the sun and their characteristic
  fine structures lend themselves to explanation. The effective
  temperature of the ion-sound waves is found to be substantially larger
  than the observed radio brightness temperature. By using the turbulent
  Bremsstrahlung mechanism for Langmuir waves, the radio luminosity can be
  accounted for. In addition, the observed radio emission from the Antares
  B companion star embedded in a stellar wind from the M supergiant is
  considered. The available free energy in a single bow shock is found
  to be far less than the observed radio luminosity. The estimated wind
  from the B star itself, however, creates a secondary shock which is
  sufficiently energetic to account for the observed emission.

Title: Radioverschijnselen als boodschappers uit de zonnecorona (3)
    continuüm-uitbarstingen en hun geheimentaal.
Authors: Fokker, A. D.; Kuijpers, J. M. E.
Bibcode: 1981Zenit...8...28F
Altcode:
  No abstract at ADS

Title: Book reviews
Authors: Verbunt, Frank; Kleczek, J.; Bleeker, J. A. M.; Kuijpers,
   Jan; Dommanget, J.
Bibcode: 1980SSRv...27..215V
Altcode:
  No abstract at ADS

Title: Comment on 'On the upconversion of ion sound to Langmuir
    turbulence,' by L. Vlahos and K. Papadopoulos
Authors: Kuijpers, J.
Bibcode: 1980ApJ...238L.165K
Altcode:
  It is shown that the production of Langmuir waves from ion sound
  by the turbulent bremsstrahlung mechanism can be more effective
  than the destruction of the Langmuir waves by the Dawson-Oberman
  resistivity. Previous conclusions to the contrary are in error owing
  to the neglect of the wave-number dependence of the ion-sound waves.

Title: Turbulent bremsstrahlung of Langmuir waves
Authors: Kuijpers, J.
Bibcode: 1980A&A....83..201K
Altcode:
  The turbulent bremsstrahlung process of Tsytovich et al. (1975) is
  reconsidered. In this mechanism the electrons that are resonant with an
  already existing nonthermal level of ion-sound waves radiate Langmuir
  waves. The efficiency of the process is derived in an independent way
  and corrections are found to the previous result. In particular it is
  found that Langmuir waves can only be produced efficiently when the
  ion-sound wave number is of the order of the Debye wave number. It
  is shown that in this case the consumed total ion-sound wave energy
  roughly equals the total amount of radiated Langmuir wave energy.

Title: Book-Review - Galaxies and Quasars
Authors: Kaufmann, W. J., III; Kuijpers, J.
Bibcode: 1980SSRv...27..216K
Altcode:
  No abstract at ADS

Title: The active radio sun.
Authors: Fokker, A. D.; Kuijpers, J. M. E.
Bibcode: 1980NTNA...46...26F
Altcode:
  No abstract at ADS

Title: Radioverschijnselen als boodschappers uit de zonnecorona
    (I). Het decor der radioverschijnselen.
Authors: Fokker, A. D.; Kuijpers, J. M. E.
Bibcode: 1980Zenit...7..334F
Altcode:
  No abstract at ADS

Title: Radioverschijnselen als boodschappers uit de zonnecorona
    (2). Kennismaking met enkele radioverschijnselen.
Authors: Fokker, A. D.; Kuijpers, J. M. E.
Bibcode: 1980Zenit...7..436F
Altcode:
  No abstract at ADS

Title: Theory of type IV DM bursts
Authors: Kuijpers, J.
Bibcode: 1980IAUS...86..341K
Altcode:
  It is noted that the study of fine structures in continuum radio
  emission from the sun is of importance in order to probe the physics
  of radio sources and of flares in particular. The existing fine
  structure theories are reviewed and an application to a radio flare
  is given. Attention is given to stationary magnetic traps including
  discussion of high frequency electrostatic instability, and high
  frequency electromagnetic instability. It is shown that the most
  important high frequency instability in such traps in the solar corona
  is the loss-cone instability of upper hybrid waves at the resonant
  surfaces. In addition, the characteristics of the most important fine
  structures in type IV dm bursts in the 160-320 MHz band as described
  mainly by Slottje (1980) are presented and the type IV dm burst of
  June 25, 1978 is examined.

Title: Pulsed Acceleration in Solar Flares
Authors: Kuijpers, J.
Bibcode: 1978A&A....69L...9K
Altcode:
  Summary It is shown that plasmaturbulence in solar flares may well
  lead to periodic acceleration of particles. The periodicity of the
  acceleration process is due to the intrinsic non-linearity of the
  coupled rate equations describing the production of ion-sound and
  Langmuir waves. Key words Solar flares, acceleration, plasma waves.

Title: Book reviews
Authors: Plavec, Miroslav; Hoekstra, R.; de Jager, C.; Grygar, Jiři;
   Otterman, J.; van den Dool, H. M.; Namba, O.; Gunsing, C. J. Th.;
   Pecker, Jean-Claude; Kwee, K. K.; Perek, L.; Callebaut, D.; Kuijpers,
   Jan; de Graaff, W.; Reijnen, G. C. M.; Swanenburg, B.; Grevesse,
   N.; Kleczek, J.; Piquet, P.; Fokker, A. D.; van Bueren, H. G.; Page,
   D. Edgar; van Duinen, R. J.; Pacini, Franco
Bibcode: 1978SSRv...21..469P
Altcode:
  No abstract at ADS

Title: Type IV dm bursts: onset and sudden reductions.
Authors: Benz, A. O.; Kuijpers, J.
Bibcode: 1976SoPh...46..275B
Altcode:
  The effect of collisions of suprathermal electrons with a thermal
  background plasma is investigated and is shown to cause flattening of a
  monotonically descending velocity distribution of fast particles. As a
  result flare-produced energetic electrons that are trapped in a coronal
  magnetic arch and that are initially distributed in energy according to
  a power-law, can give rise to an instability of Langmuir waves in the
  background plasma and the subsequent emission of continuum radiation
  as observed in type IV dm bursts.

Title: Fiber burst concurrent with a weak noise storm.
Authors: Kuijpers, J.; Slottje, C.
Bibcode: 1976SoPh...46..247K
Altcode:
  A new kind of radio burst is described and identified as quasi-fiber
  burst according to some striking similarities with fiber bursts. Its
  interpretation is discussed in terms of Kuijpers' whistler model and an
  explanation for a broken variety of. the observed burst is given. The
  derived magnetic field strength in the source is 4 G at a plasma level
  of 300 MHz.

Title: Generation of Intermediate Drift Bursts in Solar Type IV
    Radio Continua Through Coupling of Whistlers and Langmuir Waves
Authors: Kuijpers, J.
Bibcode: 1975SoPh...44..173K
Altcode:
  The possible generation of intermediate drift bursts in type IV dm
  continua through coupling between whistler waves, traveling along the
  magnetic field, and Langmuir waves, excited by a loss-cone instability
  in the source region, is elaborated. We investigate the generation,
  propagation and coupling of whistlers.

Title: A unified explanation of solar type IV dm continua and zebra
    patterns.
Authors: Kuijpers, J.
Bibcode: 1975A&A....40..405K
Altcode:
  A unified mechanism is presented for the production of type IV dm
  continuum radiation and zebra-pattern microstructure. It is shown that
  both the continuum and zebra patterns can originate in plasma waves at
  the upper hybrid frequency which are excited by a loss-cone distribution
  of fast electrons superposed on the thermal background. The zebra
  patterns will result from the electrostatic instability at source-region
  surfaces with integer ratios of electron plasma frequency/electron
  cyclotron frequency provided that the fraction of fast particles is
  small and the frequency ratio is large. A continuum will be produced
  under opposite conditions or in the same way as the zebra patterns if
  the magnetic-field inhomogeneity makes the plasma frequency vary more
  than a value equal to the average electron cyclotron frequency along
  the different harmonic surfaces.

Title: Collective wave-particle interactions in solar type IV radio
    sources.
Authors: Kuijpers, J.
Bibcode: 1975UtrOv.301.....K
Altcode:
  No abstract at ADS

Title: Collective wave-particle interactions in solar type IV
    radio sources
Authors: Kuijpers, J. M. E.
Bibcode: 1975PhDT.........1K
Altcode:
  This thesis proposes a coherent emission mechanism for type IV
  decimetric radio bursts, a unified explanation of solar type IV
  decimetric continuum storms and zebra patterns, and a possible emission
  mechanism for intermediate drift bursts. Observations of solar type
  IV bursts, continuum storms, and fine structures are reviewed. The
  fine structures and source regions are described, and velocity-space
  instabilities are analyzed. It is suggested that type IV bursts are
  produced by the induced conversion of coherently generated Cerenkov
  plasma waves into electromagnetic waves. It is proposed that continuum
  storms and zebra patterns originate in plasma waves excited at the
  upper hybrid frequency by a loss-cone distribution of fast electrons
  superposed on the ion background, that the patterns result when the
  inverse fractional density of the fast electrons exceeds the ratio of
  the electron plasma and cyclotron frequencies, and that the storms
  occur in the opposite situation. It is shown that the coupling of
  whistler solitons and Langmuir waves can produce intermediate drift
  bursts when the phase velocity of the Langmuir waves is of the order
  of the speed of light.

Title: A Coherent Radiation Mechanism for Type IV dm Radio Bursts
Authors: Kuijpers, Jan
Bibcode: 1974SoPh...36..157K
Altcode:
  An interpretation is presented of the decimetric type IV continuum with
  fine structure on March 6, 1972 and of the corresponding source region,
  in terms of Čerenkov plasma radiation and alternatively of synchrotron
  radiation, both in case of coherent and incoherent generation. If
  the magnetic field strength in the source region is a few gauss, in a
  stationary situation a loss cone instability develops which generates
  electron plasma waves coherently. The amount of energetic electrons
  required for consecutive induced scattering of the plasma waves at
  the thermal ions into electromagnetic waves is less than in case
  of synchrotron radiation. It is concluded that the former mechanism
  provides the explanation of type IV continua with fine structure such as
  intermediate drift bursts and sudden reductions of the continuum level.

Title: A Coherent Radiation Mechanism for Type IV dm Radio Bursts
Authors: Kuijpers, J.
Bibcode: 1974cesra...4..133K
Altcode:
  No abstract at ADS

Title: A possible generating mechanism for intermediate drift bursts
Authors: Kuijpers, J.
Bibcode: 1972cesra...3..130K
Altcode:
  No abstract at ADS

