Author name code: defeiter
ADS astronomy entries on 2022-09-14
author:de Feiter, L.D.
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Title: Evidence for magnetic energy storage in coronal active regions.
Authors: Krieger, A. S.; de Feiter, L. D.; Vaiana, G. S.
Bibcode: 1976SoPh...47..117K
Altcode:
  Examination of X-ray images obtained by the S-054 X-ray spectrographic
  telescope on Skylab shows the presence of some atypical X-ray emitting
  coronal structures in active regions which are not consistent with
  potential extrapolations of photospheric magnetic fields. Analysis
  of the observed temporal changes in the X-ray emitting active region
  structures demonstrates that the majority of these consist of brightness
  changes representing temperature (and perhaps, density) variations of
  the material in the loops.

Title: The Aims of the Flare Build-up Study (Introduction)
Authors: de Feiter, L. D.
Bibcode: 1976SoPh...47...15D
Altcode:
  No abstract at ADS

Title: Solar activity (Activité solaire).
Authors: Newkirk, G.; Dunn, R. B.; Mehltretter, P.; MacQueen, R.;
   Bonnet, R. M.; White, O. R.; Fokker, A. D.; Zwaan, C.; Bruzek, A.;
   Durrant, C.; Grossmann-Doerth, U.; Mehltretter, J. P.; Svestka, Z.;
   de Feiter, L. D.; Tandberg-Hanssen, E.; Howard, R.; Stix, M.; Pneuman,
   G. W.; Hundhausen, A. J.; Sawyer, C.; Simon, P.
Bibcode: 1976IAUTA..16b..13N
Altcode:
  No abstract at ADS

Title: Elementary flare bursts.
Authors: van Beek, H. F.; de Feiter, L. D.; de Jager, C.
Bibcode: 1976spre.conf..819V
Altcode: 1976spre.proc..819V
  Two hard X-ray flares observed on 2 and 7 August 1972 with the hard
  X-ray detector of the Utrecht Space Research Laboratory aboard ESRO's
  TD-1A satellite are examined in detail. It is shown that both flares can
  be decomposed completely into a number of individual Elementary Flare
  Bursts (EFB's) with no residual radiation left. For one and the same
  flare all EFB's seem to have approximately the same time profile but
  these profiles are different for the two flares investigated: the full
  widths at half maximum (FWHM) of the EFB's are 5 and 15 s respectively.

Title: Chromospheric Flares or Chromospheric Aurorae?
Authors: de Feiter, L. D.
Bibcode: 1975SSRv...17..181D
Altcode:
  This paper discusses some of the well-documented flare phenomena
  and possible analogies with magnetospheric substorm phenomena. Such
  analogies do exist, but also important differences. The combination of
  forces from magnetospheric and solar physicists will bring us closer to
  the understanding of these nearby examples of unstable cosmic plasmas.

Title: On the behaviour of the hydrogen Lyman series in flares
Authors: de Feiter, L. D.; Svestka, Z.
Bibcode: 1975SoPh...41..415D
Altcode:
  The Lyman spectrum of hydrogen has been computed for a number of flare
  models, characterized by the column density of hydrogen atoms in the
  ground state (N<SUB>1</SUB>), the electron density (n<SUB>e</SUB>)
  and the electron temperature (T<SUB>e</SUB>). Broadening by the thermal
  Doppler effect and by Stark effect has been accounted for. The source
  functions for the individual lines of the series have been derived
  from non-LTE calculations of the excitation in hydrogen flares. The
  aim of the investigation is to evaluate the use of the intensities in
  between two successive Lyman lines for a determination of the value
  for N<SUB>1</SUB>, which is a physical parameter of the flare for
  which only indirect determinations are available. Whilst in principle
  this method could give reliable results, its practical application
  meets with difficulties which hardly can be overcome. Therefore, one
  probably has to base the N<SUB>1</SUB> determination on the highest
  line resolvable in the spectrum.

Title: Solar Flare X-Ray Measurements and Their Relation to Microwave
    Bursts
Authors: de Feiter, L. D.
Bibcode: 1975IAUS...68..283D
Altcode:
  No abstract at ADS

Title: High-energy particle and photon emission of solar flares
Authors: de Feiter, L. D.
Bibcode: 1975iafe.rept...84D
Altcode:
  Particle acceleration in solar flares is investigated, and examples
  of the apparent links between high-energy particle and photon flare
  emissions are presented. Energetic electromagnetic flare emissions
  are classified as thermal or quasi-thermal, impulsive, and prolonged
  nonthermal; effects of interplanetary-magnetic-field structure on
  the properties of energetic particles as observed near earth are
  summarized. General properties of soft X-ray bursts, EUV emissions, and
  their sources are described, the components of impulsive X-ray bursts
  are identified, and the role of energetic electrons in these events is
  examined. Effects of protons and nuclei in flare regions are discussed
  with respect to the production of positron emitters, neutral pi mesons,
  neutrons, excited nuclei, and gamma rays in nuclear reactions.

Title: Solar hard X-ray bursts and accelerated electrons in solar
    flares.
Authors: de Feiter, L. D.
Bibcode: 1975lein.conf...93D
Altcode:
  No abstract at ADS

Title: Solar flare X-ray measurements and their relation to microwave
    bursts.
Authors: de Feiter, L. D.
Bibcode: 1975IAUS...68Q.283D
Altcode:
  No abstract at ADS

Title: Solar flare X-ray measurements and their relation to microwave
    bursts.
Authors: de Feiter, L. D.
Bibcode: 1975IAUS...68R.283D
Altcode:
  No abstract at ADS

Title: Book reviews
Authors: Kleczek, J.; de Feiter, L. D.; Tinbergen, J.; Elsässer,
   H.; Sciama, D. W.; Dewhirst, D. W.; Hensberge, G.
Bibcode: 1974SSRv...16..611K
Altcode:
  No abstract at ADS

Title: Solar Flares as Sources of Energetic Particles
Authors: de Feiter, L. D.
Bibcode: 1974SSRv...16....3D
Altcode:
  In this paper a review is presented of the present status of our
  knowledge of solar flare phenomena with special emphasis on the
  production of suprathermal particles and their solar effects. Of these
  energetic particles electrons play an important role since they produce
  the X-ray and radiobursts observed during many flares. Also, during
  their slowing down to thermal energies they contribute to the heating
  of localized regions in the solar atmosphere, through energy exchange
  with the ambient electrons. Observable radiations of energetic protons,
  and other nuclei, are produced through nuclear interactions leading to
  the emissions of gamma-ray lines. Detectable fluxes of these gamma-ray
  lines are produced only in the most powerful flares. Also the nuclei
  that enter into deeper layers of the solar atmosphere transfer most
  of their kinetic energy to the ambient plasma.

Title: Integrated Solar Flare Observations
Authors: de Feiter, L. D.
Bibcode: 1974cesra...4...13D
Altcode:
  No abstract at ADS

Title: Time Profiles and Photon Spectra of Solar Hard X-rays
Authors: van Beek, H. F.; de Feiter, L. D.; de Jager, C.
Bibcode: 1974ASSL...42..533V
Altcode: 1974cimo.symp..533V
  With a spectrometer aboard the ESRO TD-1A satellite, time profiles
  and photon spectra of solar X-rays have been observed in the energy
  range above 24 keV. Most of the X-ray bursts studied thus far appear
  to consist of numerous short-lived spikes with rise and decay times of
  a few seconds. Such spikes, called 'Elementary Flare Bursts' (EFB's)
  cluster together in large numbers and constitute the conventional
  high energy flare. The form of the photon spectra could be determined
  very accurately and was in all cases of the power-law type. For the
  Aug. 4, 1972 flare, the photon spectra appear to be combinations of two
  power-law spectra; for the lower energies the spectral coefficient is
  smaller than for the higher energies. The transition energy is about
  60 keV.

Title: Some critical problems of solar flare research.
Authors: de Feiter, L. D.
Bibcode: 1974spre.conf..413D
Altcode: 1974spre.meet..413D
  Some problems of current interest in the research of energetic solar
  flare phenomena are reviewed with the aim of determining the open
  questions in this field. Possible directions in which the solutions
  may be found are indicated. In this context the following problems are
  discussed: the need for a determination of the magnetic field structure
  in the chromospheric and coronal parts of an active region before,
  during and after the occurrence of a flare, the 'thermal' flares and
  their differences with respect to the impulsive flares, the energetic
  relation between the non-thermal and the thermal components of the
  high-energy flare, the implications of repetitive flare instabilities
  and continuous acceleration models, the nuclear gamma rays and neutrons
  as manifestations of the solar effects of accelerated nuclei.

Title: Hard X-ray observations of elementary flare bursts, and
    their interpretation.
Authors: van Beek, H. F.; de Feiter, L. D.; de Jager, C.
Bibcode: 1974spre.conf..447V
Altcode: 1974spre.meet..447V
  Recent observations of solar hard X-ray bursts, performed with high
  time resolution aboard the ESRO TD-1A satellite, show that often these
  bursts consist of numerous short-lived spikes with rise and decay times
  of the order of a few seconds. It is argued that these spikes, which
  are called elementary flare bursts (EFB), are the essential physical
  phenomena, which, clustered together in large numbers, constitute the
  conventional high-energy flare. For some cases studied it is found that
  the rise and decay times can be as low as 1 to 2 seconds; individual
  points deviate only slightly from this average value. These times do
  not depend on the photon energy; this seems to indicate that the EFBs
  occur at a fairly low level in the chromosphere (less than or equal to
  1500 km above the photosphere). For one particular case studied this
  conclusion is corroborated by the observation of short-lived flashes
  as observed optically with an interference filter centered at 3835
  A. In this region a considerable part of the ambient electrons are
  accelerated to energies of several tens of kiloelectron volts.

Title: Solar Flares, Suprathermal Plasma Nodules, and Loop Prominences
Authors: de Feiter, L. D.; de Jager, C.
Bibcode: 1973sari.conf...93D
Altcode:
  No abstract at ADS

Title: First results of the solar hard X-ray spectrometer on board
    the ESRO TD-1A satellite.
Authors: van Beek, H. F.; de Feiter, L. D.
Bibcode: 1973spre.conf..777V
Altcode:
  No abstract at ADS

Title: Superthermal Plasma Nodules and Their Relation to Solar Flares
Authors: De Feiter, L. D.; De Jager, C.
Bibcode: 1973SoPh...28..183D
Altcode:
  We define superthermal plasma nodules as bright points (diameter ≲
  20″), visible on high resolution X-ray heliograms. Flares appear to
  show a strong tendency to occur at the places of these nodules. There
  are indications that (part of) the hot plasma produced by consecutive
  flares is accumulated and confined in the superthermal plasma nodules,
  and that with increasing energy content of a nodule the probability
  for a drastic change of its magnetic structure increases, thus reducing
  the possibility for more flares to occur.

Title: Solar Flares
Authors: de Feiter, L.
Bibcode: 1973lsp2.conf...55D
Altcode:
  No abstract at ADS

Title: The Hard Solar X-Ray Spectrometer on Board the ESRO Td-1
    a Satellite
Authors: van Beek, H. F.; de Feiter, L. D.
Bibcode: 1973sari.conf..103V
Altcode:
  No abstract at ADS

Title: Interplanetary Solar Phenomena
Authors: de Feiter, L. D.
Bibcode: 1973sari.conf....1D
Altcode:
  No abstract at ADS

Title: The Expected Behaviour of the Hydrogen Lyman Lines in Solar
    Flares
Authors: Švestka, Z.; de Feiter, L. D.
Bibcode: 1972SSRv...13..824S
Altcode: 1972IAUCo..14..824S
  No abstract at ADS

Title: The Transient Highly Excited Solar Flare Plasma (invited Paper)
Authors: de Feiter, L. D.
Bibcode: 1972SSRv...13..827D
Altcode: 1972IAUCo..14..827D
  Recent observations of the energetic particles produced in solar
  flares indicate that the production of electrons, with energies up to
  about 100 keV, is a fairly common feature of small flares. In those
  flares the acceleration of protons and other nuclei does not extend
  beyond about 1 MeV. The X-ray emission often exhibits two distinct
  components of which the first one is produced by non-thermal, the
  second by thermal electrons through bremsstrahlung collisions with the
  ambient ions. Along with these X rays, radio emission, in the microwave
  region, is observed. This radio emission is usually interpreted as due
  to gyrosynchrotron radiation from the same electrons. In this review
  a discussion is presented of the processes occurring in solar flares
  with special reference to the acceleration and radiation processes.

Title: Summary of the Panel Discussions
Authors: de Feiter, L. D.
Bibcode: 1972SSRv...13..361D
Altcode:
  No abstract at ADS

Title: Introduction
Authors: de Feiter, L. D.
Bibcode: 1972SSRv...13..197D
Altcode:
  No abstract at ADS

Title: Epilogue by the Editors
Authors: Kremser, G.; de Feiter, L. D.
Bibcode: 1972SSRv...13..365K
Altcode:
  No abstract at ADS

Title: Abstracts of papers from other journals
Authors: De Feiter, L. D.; Pasachoff, Jay M.; Vassilyeva, G.; Gussmann,
   E. A.; Vassilyeva, G. J.; Henoux, J. -C.; Uchida, Y.; Namba, O.
Bibcode: 1972SoPh...23..501D
Altcode:
  No abstract at ADS

Title: Neutron and gamma-ray emission from white-light flares.
Authors: de Feiter, L. D.; Svestka, Z.
Bibcode: 1972spre.conf.1547D
Altcode: 1972spre....2.1547D
  No abstract at ADS

Title: Abstracts of papers from other journals
Authors: Henoux, J. -C.; De Feiter, L. D.; Ambroš, P.; Pasachoff,
   JAY M.
Bibcode: 1972SoPh...22..252H
Altcode:
  No abstract at ADS

Title: Abstracts of papers from other journals
Authors: De Feiter, L. D.; Vassilyeva, G.; Henoux, J. -C.; Ambrož,
   Pavel
Bibcode: 1971SoPh...20..517D
Altcode:
  No abstract at ADS

Title: On the Flux of Gamma Rays from Solar Flares
Authors: De Feiter, L. D.
Bibcode: 1971SoPh...19..207D
Altcode:
  No abstract at ADS

Title: Abstracts of papers from other journals
Authors: Pasachoff, Jay M.; Henoux, J. -C.; de Feiter, L. D.
Bibcode: 1971SoPh...17..277P
Altcode:
  No abstract at ADS

Title: Book reviews
Authors: de Graaf, T.; Houziauk, L.; de Pater, A. D.; de Feiter,
   L. D.; Hundhausen, A. J.; Veldkamp, J.; Axford, W. Ian
Bibcode: 1970SSRv...11..593D
Altcode:
  No abstract at ADS

Title: Book reviews
Authors: de Jager, C.; King-Hele, D. G.; Heise, John; ĹEna, P.;
   Somoza, R.; Lindblad, Per Olof; Ritchey, H. W.; de Feiter, L. D.
Bibcode: 1970SSRv...10..737D
Altcode:
  No abstract at ADS

Title: Abstracts of papers from other journals
Authors: Uchida, Y.; Gussmann, E. A.; De Feiter, L. D.; Henoux,
   J. -C.; Stepanyan, N. N.; Pasachoff, Jay. M.
Bibcode: 1970SoPh...11..173U
Altcode:
  No abstract at ADS

Title: Abstracts of papers from other journals
Authors: Stepanyan, N.; Pasachoff, Jay M.; Ambrož, P.; Vassilyeva,
   G.; Henoux, J. -C.; Fokker, A. D.; De Feiter, L. D.; Gussmann, E. A.;
   Uchida, Y.; Namba, O.
Bibcode: 1969SoPh....8..491S
Altcode:
  No abstract at ADS

Title: Abstracts of papers from other journals
Authors: Pasachoff, Jay M.; Gussmann, E. A.; Stepanyan, N. N.; de
   Feiter, L. D.; Uchida, Yutaka; Švestka, Z.; Vassilyeva, G. J.
Bibcode: 1969SoPh....6..155P
Altcode:
  No abstract at ADS

Title: On the development and activity of the active region associated
with the proton flare event of July 1966: Summary of observations
    and conclusions.
Authors: Banin, V.; de Feiter, L. D.; Fokker, A. D.; Martres, M. -J.;
   Pick, M.
Bibcode: 1969AIQSY...3..229B
Altcode:
  No abstract at ADS

Title: Book reviews
Authors: de Feiter, L. D.; de Jager, C.
Bibcode: 1968SoPh....3..623D
Altcode: 1968SoPh....3..623.
  No abstract at ADS

Title: Analysis of the Balmar spectrum of solar flares
Authors: de Feiter, Leendert Dirk
Bibcode: 1966abss.book.....D
Altcode: 1966QB526.F6F4.....
  No abstract at ADS

Title: Analysis of the Balmer spectrum of solar flares
Authors: de Feiter, Leendert Dirk
Bibcode: 1966RAOU...18R....D
Altcode:
  No abstract at ADS

Title: Analysis of the Balmer spectrum of solar flares
Authors: de Feiter, Leendert Dirk
Bibcode: 1966PhDT........69D
Altcode:
  No abstract at ADS

Title: On the Stark Broadening of High Balmer Lines Emitted by
    Solar Flares
Authors: de Feiter, L. D.
Bibcode: 1964NASSP..50...81D
Altcode: 1964psf..conf...81D
  No abstract at ADS

Title: Time variation of electron density in a large solar flare
Authors: de Feiter, L. D.; Švestka, Z.
Bibcode: 1964BAICz..15..117D
Altcode:
  No abstract at ADS

Title: Details of the Relations between Type IV-Outbursts and
    sc-Geomagnetic Storms
Authors: Roosen, J.; de Feiter, L. D.
Bibcode: 1962JPSJS..17A..49R
Altcode: 1962ICRC....7A..49R; 1962JPSJ...17A..49R; 1962PSJaP..17A..49R
  No abstract at ADS

Title: On Maximum of Cosmic-Ray Intensity prior to a Prebaisse-Effect
Authors: de Feiter, L. D.; Legrand, J. P.
Bibcode: 1962JPSJS..17B.272D
Altcode: 1962ICRC....7B.272D; 1962PSJaP..17B.272D; 1962JPSJ...17B.272D
  No abstract at ADS

Title: On the production of solar radio outbursts in different
    centres of activity
Authors: de Feiter, L. D.; Fokker, A. D.
Bibcode: 1961BAN....15..319D
Altcode:
  No abstract at ADS

Title: The Cosmic Ray Flares of November 12 and 15, 1960
Authors: De Feiter, L. D.; Freon, A.; Legrand, J. P.
Bibcode: 1961spre.conf..776D
Altcode:
  No abstract at ADS

Title: The cosmic ray flares of Nov. 12 and 15. 1960.
Authors: Legrand, J. P.; de Feiter, L. D.; Freon, A.
Bibcode: 1961PRNAA..64..325L
Altcode: 1961RNAAS..64..325L
  No abstract at ADS

Title: Solar radio events and geomagnetic storms
Authors: De Feiter, L. D.; Fokker, A. D.; Van Lohuizen, H. P. Th.;
   Roosen, J.
Bibcode: 1960P&SS....2..223D
Altcode:
  On the basis of a 24-hr patrol of solar radio noise established since
  the beginning of the International Geophysical Year, an identification
  is attempted of those solar flares which, on account of their associated
  radio responses, most probably were the cause of a geomagnetic
  storm. The cases for which we think the identification to be reliable
  are listed. It has appeared that great integrated intensity of the radio
  outburst at centimeter, decimeter and meter wavelengths is the primary
  criterion for identifying the solar flares responsible. Most of these
  giant radio outbursts, to which we assigned the "radio importance"
  figure 3 +, belong to the so-called type IV. Only a minor fraction
  of these events were accompanied by slow-drift bursts of type II. Of
  the importance 3 + radio outbursts about 60 per cent are clearly
  associated with the subsequent sudden commencement of a geomagnetic
  storm. Conversely, about 50 per cent of the sudden commencements of
  a storm can be related to an important radio event. Some reasons, why
  in a particular case the storm-outburst association may fail to exist,
  are mentioned.

Title: The profiles of Hα in solar flares
Authors: de Feiter, L. D.
Bibcode: 1960AnAp...23..970D
Altcode:
  No abstract at ADS

Title: Association of Radio Outbursts with Solar Flares
Authors: de Feiter, L. D.; Fokker, A. D.; Roosen, J.
Bibcode: 1959Natur.184..805D
Altcode:
  SEVERAL authors have paid attention to the association of radio
  outbursts with solar flares, for example, Dodson<SUP>1</SUP> and
  Loughhead, Roberts and McCabe<SUP>2</SUP>. Outstanding flare events
  are very commonly accompanied by a radio event at decimeter and/or
  metre wave-lengths; but only a minor fraction of the less-important
  flares produce a distinctive radio event.

Title: Eclipse observations of solar radio-frequency radiation on 200,
    545 3000, and 9100 Mc/s
Authors: Fokker, A. D.; de Munck, J. C.; de Feiter, L. D.
Bibcode: 1956sei..conf..272F
Altcode:
  No abstract at ADS

