Author name code: manchester
ADS astronomy entries on 2022-09-14
author:"Manchester, Ward B. IV" 
------------------------------------------------------------------------  

Title: Modeling FETCH Observations of 2005 May 13 CME
Authors: Jensen, Elizabeth A.; Manchester, Ward B., IV; Wexler,
   David B.; Kooi, Jason E.; Nieves-Chinchilla, Teresa; Jian, Lan K.;
   Pevtsov, Alexei; Fung, Shing
Bibcode: 2022arXiv220903350J
Altcode:
  This paper evaluates the quality of CME analysis that has been
  undertaken with the rare Faraday rotation observation of an
  eruption. Exploring the capability of the FETCH instrument hosted on
  the MOST mission, a four-satellite Faraday rotation radio sounding
  instrument deployed between the Earth and the Sun, we discuss the
  opportunities and challenges to improving the current analysis
  approaches.

Title: Three-Dimensional Structure of the Corona During WHPI Campaign
    Rotations CR-2219 and CR-2223
Authors: Lloveras, D. G.; Vásquez, A. M.; Nuevo, F. A.; Frazin, R. A.;
   Manchester, W.; Sachdeva, N.; Van der Holst, B.; Lamy, P.; Gilardy, H.
Bibcode: 2022JGRA..12730406L
Altcode:
  Differential emission measure tomography (DEMT) and white light
  (WL) tomography were applied to study the three-dimensional (3D)
  structure of the global solar corona for two Whole Heliosphere
  and Planetary Interactions campaign periods, Carrington rotations
  2219 and 2223. With DEMT, Solar Dynamics Observatory/Atmospheric
  Imaging Assembly images were used to reconstruct the 3D coronal
  electron density and temperature in the range of heliocentric
  distance 1.02-1.25 R<SUB>⊙</SUB>. With WL tomography, Solar and
  Heliospheric Observatory/Large Angle and Spectrometric COronagraph-C2
  images were used to reconstruct the 3D electron density in the range
  of heliocentric distance 2.5-6.0 R<SUB>⊙</SUB>. The two periods
  were also simulated with the 3D-magneto-hydrodynamic Alfvén Wave
  Solar Model (AWSoM), and its results compared in detail with the
  reconstructions. The DEMT analysis reveals a 20% less dense and 20%
  hotter corona than for rotations corresponding to the solar cycle
  23/24 deep minimum. The electron density and temperature of the AWSoM
  model agree with DEMT results within 10% and 20%, respectively, while
  its electron density overestimates results of WL tomography up to
  75%. The slow (fast) component of the terminal wind speed of the model
  is found to be associated with field lines characterized by larger
  (smaller) values of the tomographic density and temperature at the
  coronal base. DEMT reconstructions reveal the coronal plasma to be
  ubiquitously characterized by temperature variability of up to ≈45%
  over spatial scales of order ∼10<SUP>4</SUP> km. Taking into account
  this level of fine-structure by global models may be consequential
  for their predictions on wave propagation in the corona.

Title: Modern Faraday Rotation Studies to Probe the Solar Wind
Authors: Kooi, Jason E.; Wexler, David B.; Jensen, Elizabeth A.;
   Kenny, Megan N.; Nieves-Chinchilla, Teresa; Wilson, Lynn B., III; Wood,
   Brian E.; Jian, Lan K.; Fung, Shing F.; Pevtsov, Alexei; Gopalswamy,
   Nat; Manchester, Ward B.
Bibcode: 2022FrASS...941866K
Altcode:
  For decades, observations of Faraday rotation have provided unique
  insights into the plasma density and magnetic field structure of
  the solar wind. Faraday rotation (FR) is the rotation of the plane
  of polarization when linearly polarized radiation propagates through
  a magnetized plasma, such as the solar corona, coronal mass ejection
  (CME), or stream interaction region. FR measurements are very versatile:
  they provide a deeper understanding of the large-scale coronal magnetic
  field over a range of heliocentric distances (especially ≈1.5 to
  20 R⊙) not typically accessible to in situ spacecraft observations;
  detection of small-timescale variations in FR can provide information
  on magnetic field fluctuations and magnetohydrodynamic wave activity;
  and measurement of differential FR can be used to detect electric
  currents. FR depends on the integrated product of the plasma
  density and the magnetic field component along the line of sight
  to the observer; historically, models have been used to distinguish
  between their contributions to FR. In the last two decades, though,
  new methods have been developed to complement FR observations with
  independent measurements of the plasma density based on the choice
  of background radio source: calculation of the dispersion measure
  (pulsars), measurement of Thomson scattering brightness (radio
  galaxies), and application of radio ranging and apparent-Doppler
  tracking (spacecraft). New methods and new technology now make it
  possible for FR observations of solar wind structures to return not
  only the magnitude of the magnetic field, but also the full vector
  orientation. In the case of a CME, discerning the internal magnetic
  flux rope structure is critical for space weather applications.

Title: The impact of coronal mass ejections and flares on the
    atmosphere of the hot Jupiter HD189733b
Authors: Hazra, Gopal; Vidotto, Aline A.; Carolan, Stephen; Villarreal
   D'Angelo, Carolina; Manchester, Ward
Bibcode: 2022MNRAS.509.5858H
Altcode: 2021arXiv211104531H; 2021MNRAS.tmp.3019H
  High-energy stellar irradiation can photoevaporate planetary
  atmospheres, which can be observed in spectroscopic transits of hydrogen
  lines. For the exoplanet HD189733b, multiple observations in the Ly α
  line have shown that atmospheric evaporation is variable, going from
  undetected to enhanced evaporation in a 1.5-yr interval. Coincidentally
  or not, when HD189733b was observed to be evaporating, a stellar flare
  had just occurred 8 h prior to the observation. This led to the question
  of whether this temporal variation in evaporation occurred due to the
  flare, an unseen associated coronal mass ejection (CME), or even the
  simultaneous effect of both. In this work, we investigate the impact of
  flares (radiation), winds, and CMEs (particles) on the atmosphere of
  HD189733b using three-dimensional radiation hydrodynamic simulations
  that self-consistently include stellar photon heating. We study four
  cases: first, the quiescent phase including stellar wind; secondly,
  a flare; thirdly, a CME; and fourthly, a flare that is followed by
  a CME. Compared to the quiescent case, we find that the flare alone
  increases the evaporation rate by only 25 per cent, while the CME leads
  to a factor of 4 increments. We calculate Ly α synthetic transits and
  find that the flare alone cannot explain the observed high blueshifted
  velocities seen in the Ly α. The CME, however, leads to an increase
  in the velocity of escaping atmospheres, enhancing the blueshifted
  transit depth. While the effects of CMEs show a promising potential,
  our models are not able to fully explain the blueshifted transit depths,
  indicating that they might require additional physical mechanisms.

Title: Improving the Alfvén Wave Solar Atmosphere Model Based on
    Parker Solar Probe Data
Authors: van der Holst, B.; Huang, J.; Sachdeva, N.; Kasper, J. C.;
   Manchester, W. B., IV; Borovikov, D.; Chandran, B. D. G.; Case, A. W.;
   Korreck, K. E.; Larson, D.; Livi, R.; Stevens, M.; Whittlesey, P.;
   Bale, S. D.; Pulupa, M.; Malaspina, D. M.; Bonnell, J. W.; Harvey,
   P. R.; Goetz, K.; MacDowall, R. J.
Bibcode: 2022ApJ...925..146V
Altcode:
  In van der Holst et al. (2019), we modeled the solar corona and inner
  heliosphere of the first encounter of NASA's Parker Solar Probe (PSP)
  using the Alfvén Wave Solar atmosphere Model (AWSoM) with Air Force
  Data Assimilative Photospheric flux Transport-Global Oscillation Network
  Group magnetograms, and made predictions of the state of the solar
  wind plasma for the first encounter. AWSoM uses low-frequency Alfvén
  wave turbulence to address the coronal heating and acceleration. Here,
  we revise our simulations, by introducing improvements in the energy
  partitioning of the wave dissipation to the electron and anisotropic
  proton heating and using a better grid design. We compare the new AWSoM
  results with the PSP data and find improved agreement with the magnetic
  field, turbulence level, and parallel proton plasma beta. To deduce the
  sources of the solar wind observed by PSP, we use the AWSoM model to
  determine the field line connectivity between PSP locations near the
  perihelion at 2018 November 6 UT 03:27 and the solar surface. Close
  to the perihelion, the field lines trace back to a negative-polarity
  region about the equator.

Title: Predicting the Optimal Poynting Flux for Different Solar
    Activity Conditions for Realtime Solar Wind Prediction
Authors: Huang, Zhenguang; Toth, Gabor; Gombosi, Tamas; Sachdeva,
   Nishtha; Zhao, Lulu; Manchester, Ward; van der Holst, Bart; Sokolov,
   Igor
Bibcode: 2021AGUFMSH45D2395H
Altcode:
  Its critical to have an accurate solar wind background in the inner
  heliosphere for space weather prediction, from the arrival of Corotating
  Interaction Regions (CIRs), to the Coronal Mass Ejections (CMEs),
  and Solar Energetic Particles (SEPs). In the space weather community,
  there are two major approaches to predict the solar wind background:
  one uses empirical or semi-empirical models, e.g., the Wang-Sheeley-Arge
  (WSA) model; the other is based on first-principles model, e.g., the
  Alfven Wave Solar atmosphere Model (AWSoM) developed at the University
  of Michigan. In the past, it was difficult for physics models to
  perform real-time solar wind predictions, because the computational
  cost is much higher for physics-based models than for empirical or
  semi-empirical models, and the optimal input parameters could be
  different for different solar rotations in which case the user would
  need to run the model with different input parameters to best predict
  the solar wind. Nowadays, the computational cost is not a big issue
  as super computers are much more powerful than before. The remaining
  issue is that the input parameters could vary. In real-time solar
  wind prediction, it is necessary to have optimal input parameters in
  advance. In this presentation, we study the relation between one of the
  most important parameters for AWSoM, the Poynting flux at the inner
  boundary, and the magnetic field structure of the solar corona. We
  obtain the optimal Poynting flux value for nine Carrington rotations
  in the last solar cycle and correlate it with various characteristics
  of the solar magnetic field, such as open flux, area of coronal holes,
  etc.. The preliminary results are encouraging, and suggest that the
  optimal parameter can be estimated from the magnetograms.

Title: SOFIE (Solar-wind with Field-lines and Energetic-particles):
    A data-driven and self-consistent SEP modeling and forecasting tool
Authors: Zhao, Lulu; Sokolov, Igor; Gombosi, Tamas; Tenishev, Valeriy;
   Huang, Zhenguang; Toth, Gabor; Sachdeva, Nishtha; Manchester, Ward;
   van der Holst, Bart
Bibcode: 2021AGUFMSH55F1900Z
Altcode:
  We present a data-driven and self-consistent SEP model, SOFIE, to
  simulate the acceleration and transport processes of energetic particles
  using the Space Weather Modeling Framework (SWMF). In this model, the
  background solar wind plasma in the solar corona and interplanetary
  space are modeled by the Alfven Wave Solar-atmosphere Model(-Realtime)
  (AWSoM(-R)) driven by the near-real-time hourly updated GONG (bihourly
  ADAPT-GONG) magnetograms. In the background solar wind, the CMEs
  are launched employing the Eruptive Event Generator using Gibson-Low
  configuration (EEGGL), by inserting a flux rope estimated from the free
  magnetic energy in the active region. The acceleration and transport
  processes are then modeled self-consistently by the multiple magnetic
  field line tracker (M-FLAMPA) and the Adaptive Mesh Particle Simulator
  (AMPS). We will demonstrate the capability of SOFIE to demystify the
  acceleration processes by the CME-driven shock in the low corona and the
  modulation of energetic particles by the solar wind structures. Besides,
  using selected historical SEP events, e.g. 2013 Apr 11 event, we will
  illustrate the progresses toward a faster-than-real-time prediction
  of SEPs.

Title: AWSoM MHD simulation of a solar active region with realistic
    spectral synthesis
Authors: Manchester, Ward; Shi, Tong; Landi, Enrico; Szente, Judit;
   van der Holst, Bart; Chen, Yuxi; Toth, Gabor; Bertello, Luca; Pevtsov,
   Alexander
Bibcode: 2021AGUFMSH12B..02M
Altcode:
  For the first time, we simulate the detailed spectral line emission
  from a solar active region (AR) with the Alfven Wave Solar Model
  (AWSoM). We select an active region appearing near disk center on
  2018 July 13 and use an NSO-HMI synoptic magnetogram to specify the
  magnetic field at the model's inner boundary. To resolve smaller-scale
  magnetic features, we apply adaptive mesh refinement to resolve the
  AR with a spatial resolution of 0.37 degrees, four times higher than
  the background corona. We then apply the SPECTRUM code informed with
  Chianti spectral emissivities to calculate more than a dozen spectral
  lines forming at temperatures ranging from 0.5 to 3+ MK. Comparisons
  are made between these simulated line profiles and those observed by
  the Hinode/EIS instrument where we find close agreement (within a
  20% margin of error of peak intensity) across a wide range of loop
  sizes and temperatures. We also compare the differential emission
  measure calculated from both the simulation and EIS observation to
  further show the model's ability to capture the plasma temperature and
  density. Finally, we simulate and compare Doppler velocities and find
  that simulated flow patterns to be of comparable magnitude to what
  is observed. Our results demonstrate the broad applicability of the
  low-frequency Alfven wave balanced turbulence theory for explaining
  the heating of coronal loops.

Title: AWSoM context simulations for Parker Solar Probe encounter 7
Authors: van der Holst, Bart; Manchester, Ward; Klein, Kristopher
Bibcode: 2021AGUFMSH15C2045V
Altcode:
  We compare Alfven Wave Solar atmosphere Model (AWSoM) simulations
  with the seventh orbit of NASAs Parker Solar Probe (PSP). The
  perihelion of this encounter is 20.3 Rsun reached at 2021-01-01. In
  the AWSoM model, the coronal heating and acceleration is addressed
  via low-frequency, reflection-driven Alfven waves. The nonlinear
  interaction of counter-propagating waves results in a turbulent energy
  cascade. The dissipated wave energy is then apportioned to electron and
  anisotropic proton temperatures. We check the ability of the simulations
  to reproduce the observed plasma mass density, velocity, and magnetic
  fields, temperature anisotropy, and wave turbulence levels. To deduce
  the sources of the solar wind observed by PSP we use the AWSoM model
  to determine the field line connectivity between PSP locations and the
  Sun. We will also describe the large-scale structures that PSP might
  have passed through, for instance whether PSP was in the fast or slow
  wind and when PSP crossed the heliospheric current sheet. We emphasize
  the proton temperature anisotropies and check for the occurrence of
  plasma instabilities.

Title: Novel Magnetic Field and Electron Density Measurements of
    CMEs (within AU) with the Proposed Multiview Observatory for Solar
    Terrestrial Science (MOST) Mission
Authors: Jensen, P. E., C. S. P., Elizabeth; Manchester, Ward; Fung,
   Shing; Gopalswamy, Nat; Jian, Lan; Kenny, Megan; Kooi, Jason; Lazio,
   Joseph; Li, Lihua; Nieves-Chinchilla, Teresa; Pevtsov, Alexei; Wexler,
   David; Wilson, Lynn; Wood, Brian; Bale, Stuart; Bastian, Tim
Bibcode: 2021AGUFMSH33A..08J
Altcode:
  The Multiview Observatory for Solar Terrestrial Science (MOST) mission
  concept will be the most advanced solar observatory to date (Gopalswamy
  et al, SH0001, 2021). Comprising four spacecraft, two located in the L4
  and ahead of L4 position and two located in the L5 and behind of the L5
  position, the four lines-of-sight (LOSs) form the basis for the unique
  Faraday Effect Tracker of Coronal and Heliospheric Structures (FETCH)
  instrument (Wexler et al, SH0019, 2021). We report on our modeling
  into the expected Faraday rotation (FR) caused by an Earth-directed
  CME crossing the MOST/FETCH radio-sensing paths using a heliospheric
  3-D MHD model to obtain the necessary LOS data on electron density
  and magnetic field components (see example image). Specifically, we
  utilized simulation data of the 2005 May 13 CME (Manchester IV et al.,
  2014, Plasma Phys. Control. Fusion), which erupted from the north-south
  polarity inversion line of AR 10759 at 16:03 UT, reaching speeds around
  2000 km/s in the corona. The trajectory of the CME at an acute angle
  to the Earth-Sun line crosses each FETCH LOS at a different time. Two
  LOSs are at different viewing angles with little overlap between
  the CME sheath and magnetic flux rope core. A blind test fitting of
  the Faraday rotation functions (Figures 6 and 7 in Jensen et al.,
  2010, Sol. Phys.) to the simulated FETCH observations reproduced the
  orientation of the CME for its handedness as well as its associated
  complementary degenerate solution. In conclusion, one of the four
  LOSs will be more sensitive to observing CME flux rope structure of
  Earthward CMEs, depending on their trajectory. We find that two of the
  four LOSs enable analyzing CME evolution, whereas the other two LOSs
  enable analyzing the average magnetic field vector in the corresponding
  high density regions dominating the measurements at that time. For
  example, the average sheath magnetic field vector can be partially
  measured in the plane of the ecliptic due to the angular differences
  between 2 LOSs. We discuss future work as this effort develops.

Title: FETCH Concept: Investigating Quiescent and Transient Magnetic
    Structures in the Inner Heliosphere using Faraday Rotation of
    Spacecraft Radio Signals
Authors: Wexler, David; Jensen, Elizabeth; Gopalswamy, Nat; Wilson,
   Lynn; Fung, Shing; Nieves-Chinchilla, Teresa; Jian, Lan; Bastian,
   Tim; Pevtsov, Alexei; Manchester, Ward; Kenny, Megan; Lazio, Joseph;
   Wood, Brian; Kooi, Jason
Bibcode: 2021AGUFMSH31A..05W
Altcode:
  The Faraday Effect Tracker of Coronal and Heliospheric structures
  (FETCH) is a new instrument concept being developed to probe coronal
  and interplanetary magnetic field structures in the ambient solar wind,
  corotating interaction regions and coronal mass ejections (CMEs) as
  they evolve in the inner heliosphere. FETCH is one of the instruments
  that constitute the Multiview Observatory for Solar Terrestrial (MOST)
  science mission. FETCH will measure Faraday rotation (FR) of linearly
  polarized spacecraft radio signals transmitted along four lines of sight
  provided by the four MOST spacecraft: two large spacecraft deployed
  at Sun-Earth Lagrange points 4 and 5 and two smaller spacecraft, one
  ahead of L4 and the other behind L5. FETCH will transmit and receive at
  selected radio frequencies in the 1-100 MHz range for lines of sight
  with solar impact parameters &lt; 0.5 AU. FR yields the line-of-sight
  (LOS) integrated product of electron number density and LOS-projected
  magnetic field strengths. The FR measurements will be obtained from
  the Stokes polarization parameters while additional plasma parameters,
  such as electron column density, will be extracted from other signal
  diagnostics. The multifrequency FR data and four lines-of-sight
  will be used to constrain the magnetic field topology and dynamics of
  interplanetary plasma structures upstream from Earth. Unique to this FR
  experiment, the FETCH transmitter-receiver instrumentation is positioned
  such that the entire sensing path remains in interplanetary space, thus
  avoiding the complications of trans-ionospheric FR observations. The
  FETCH key science objectives include: (1) characterizing CME magnetic
  field structure and flux rope orientation, (2) tracking CME propagation
  and shock signatures, (3) understanding the magnetic field features
  of corotating interaction regions in the extended corona and inner
  heliosphere, and (4) determination of large-scale MHD wave organization
  in regions of developed ambient solar wind and its evolution during
  perturbed flows. The MOST mission will build upon the achievements of
  the Solar Heliospheric Observatory (SOHO) and the Solar Terrestrial
  Relations Observatory (STEREO) missions during the last couple of
  decades. FETCH will help fill the long-standing measurement gap of
  magnetic field data in the inner heliosphere.

Title: The Multiview Observatory for Solar Terrestrial Science (MOST)
Authors: Gopalswamy, Nat; Kucera, Therese; Leake, James; MacDowall,
   Robert; Wilson, Lynn; Kanekal, Shrikanth; Shih, Albert; Christe,
   Steven; Gong, Qian; Viall, Nicholeen; Tadikonda, Sivakumar; Fung,
   Shing; Yashiro, Seiji; Makela, Pertti; Golub, Leon; DeLuca, Edward;
   Reeves, Katharine; Seaton, Daniel; Savage, Sabrina; Winebarger, Amy;
   DeForest, Craig; Desai, Mihir; Bastian, Tim; Lazio, Joseph; Jensen,
   P. E., C. S. P., Elizabeth; Manchester, Ward; Wood, Brian; Kooi,
   Jason; Wexler, David; Bale, Stuart; Krucker, Sam; Hurlburt, Neal;
   DeRosa, Marc; Pevtsov, Alexei; Tripathy, Sushanta; Jain, Kiran;
   Gosain, Sanjay; Petrie, Gordon; Kholikov, Shukirjon; Zhao, Junwei;
   Scherrer, Philip; Woods, Thomas; Chamberlin, Philip; Kenny, Megan
Bibcode: 2021AGUFMSH12A..07G
Altcode:
  The Multiview Observatory for Solar Terrestrial Science (MOST) is a
  comprehensive mission concept targeting the magnetic coupling between
  the solar interior and the heliosphere. The wide-ranging imagery and
  time series data from MOST will help understand the solar drivers and
  the heliospheric responses as a system, discerning and tracking 3D
  magnetic field structures, both transient and quiescent in the inner
  heliosphere. MOST will have seven remote-sensing and three in-situ
  instruments: (1) Magnetic and Doppler Imager (MaDI) to investigate
  surface and subsurface magnetism by exploiting the combination of
  helioseismic and magnetic-field measurements in the photosphere; (2)
  Inner Coronal Imager in EUV (ICIE) to study large-scale structures
  such as active regions, coronal holes and eruptive structures by
  capturing the magnetic connection between the photosphere and the
  corona to about 3 solar radii; (3) Hard X-ray Imager (HXI) to image
  the non-thermal flare structure; (4) White-light Coronagraph (WCOR) to
  seamlessly study transient and quiescent large-scale coronal structures
  extending from the ICIE field of view (FOV); (5) Faraday Effect
  Tracker of Coronal and Heliospheric structures (FETCH), a novel radio
  package to determine the magnetic field structure and plasma column
  density, and their evolution within 0.5 au; (6) Heliospheric Imager
  with Polarization (HIP) to track solar features beyond the WCOR FOV,
  study their impact on Earth, and provide important context for FETCH;
  (7) Radio and Plasma Wave instrument (M/WAVES) to study electron beams
  and shocks propagating into the heliosphere via passive radio emission;
  (8) Solar High-energy Ion Velocity Analyzer (SHIVA) to determine spectra
  of electrons, and ions from H to Fe at multiple spatial locations
  and use energetic particles as tracers of magnetic connectivity; (9)
  Solar Wind Magnetometer (MAG) to characterize magnetic structures at
  1 au; (10) Solar Wind Plasma Instrument (SWPI) to characterize plasma
  structures at 1 au. MOST will have two large spacecraft with identical
  payloads deployed at L4 and L5 and two smaller spacecraft ahead of L4
  and behind L5 to carry additional FETCH elements. MOST will build upon
  SOHO and STEREO achievements to expand the multiview observational
  approach into the first half of the 21st Century.

Title: Global Sensitivity Analysis for Solar-Wind Simulations in
    the Space Weather Modelling Framework
Authors: Jivani, Aniket; Huan, Xun; Chen, Yang; van der Holst, Bart;
   Zou, Shasha; Huang, Zhenguang; Sachdeva, Nishtha; Iong, Daniel;
   Manchester, Ward; Toth, Gabor
Bibcode: 2021AGUFMSH55C1851J
Altcode:
  The Space Weather Modelling Framework (SWMF) offers efficient and
  flexible sun-to-earth simulations based on coupled first principles
  and/or empirical models. This encompasses computing the quiet solar
  wind, generating a coronal mass ejection (CME), propagating the CME
  through the heliosphere, and calculating the magnetospheric impact via
  geospace models. The predictions from these different steps and models
  are affected by uncertainty and variation of many model inputs and
  parameters, such as the Poynting flux emanating from the photosphere
  and driving and heating the solar wind. In this presentation, as part
  of the NextGen SWMF project funded by NSF, we perform uncertainty
  quantification (UQ) for the quiet solar wind simulations produced by
  our Alfven Wave Solar atmosphere Model (AWSoM). We first catalogue
  the various sources of uncertainty and their distributions, and then
  propagate the uncertainty to key predictive quantities of interest, the
  in-situ solar wind and magnetic field at 1 au, through space-filling
  designs of high-fidelity simulations. Using this dataset, we then
  build polynomial chaos surrogate models that offer a convenient route
  to global sensitivity analysis, which quantifies the contribution
  of each input parameters uncertainty towards the variability of the
  QoIs. The resulting Sobol sensitivity index allows us to rank and retain
  only the most impactful parameters going forward, thereby achieving
  dimension-reduction of the stochastic space. We have performed this
  UQ analysis for both solar maximum and solar minimum conditions,
  and we will summarize our findings in this presentation.

Title: Developing the Michigan Sun-to-Earth Model with Data
    Assimilation and Quantified Uncertainty
Authors: Toth, Gabor; Chen, Yang; Huan, Xun; van der Holst, Bart;
   Zou, Shasha; Jivani, Aniket; Iong, Daniel; Sachdeva, Nishtha; Huang,
   Zhenguang; Chen, Yuxi; Gaenko, Alexander; Manchester, Ward
Bibcode: 2021AGUFMSH53B..06T
Altcode:
  As part of the Space Weather with Quantified Uncertainty program, our
  project, funded by NSF, has been working on developing the Michigan
  Sun-to-Earth Model with Data Assimilation and Quantified Uncertainty
  (MSTEM-QUDA). In this talk we will summarize the main goals of the
  project and report our progress. Using sophisticated experimental
  design and fully automated scripts, we have performed many hundreds
  of simulations with our solar corona and heliosphere model generating
  steady state solar wind solutions. Based on these simulations, we have
  completed the uncertainty quantification analysis. One important finding
  is that the physically meaningful range of certain model parameters
  depends on the solar cycle. We will use an ensemble of background
  solar wind model solutions as a starting point for simulating coronal
  mass ejections. Our preliminary model runs show promising accuracy for
  the CME arrival time. We have also ported the Geospace model, a large
  part of MSTEM-QUDA, to run efficiently on a GPU. In fact, we can run
  the operational Geospace model on a single GPU significantly faster
  than real time at the same speed as using about 100 CPU cores. The
  Michigan Sun-to-Earth Model is available as an open-source distribution
  at https://github.com/MSTEM-QUDA to the entire community.

Title: Tracking the Source of Solar Type II Bursts through Comparisons
    of Simulations and Radio Data
Authors: Hegedus, Alexander M.; Manchester, Ward B.; Kasper, Justin C.
Bibcode: 2021ApJ...922..203H
Altcode: 2021arXiv210207875H
  The most intense solar energetic particle events are produced by
  coronal mass ejections (CMEs) accompanied by intense type II radio
  bursts below 15 MHz. Understanding where these type II bursts are
  generated relative to an erupting CME would reveal important details
  of particle acceleration near the Sun, but the emission cannot
  be imaged on Earth due to distortion from its ionosphere. Here,
  a technique is introduced to identify the likely source location of
  the emission by comparing the dynamic spectrum observed from a single
  spacecraft against synthetic spectra made from hypothesized emitting
  regions within a magnetohydrodynamic (MHD) numerical simulation of the
  recreated CME. The radio-loud 2005 May 13 CME was chosen as a test case,
  with Wind/WAVES radio data being used to frame the inverse problem
  of finding the most likely progression of burst locations. An MHD
  recreation is used to create synthetic spectra for various hypothesized
  burst locations. A framework is developed to score these synthetic
  spectra by their similarity to the type II frequency profile derived
  from the Wind/WAVES data. Simulated areas with 4× enhanced entropy and
  elevated de Hoffmann-Teller velocities are found to produce synthetic
  spectra similar to spacecraft observations. A geometrical analysis
  suggests the eastern edge of the entropy-derived shock around (-30°,
  0°) was emitting in the first hour of the event before falling off,
  and the western/southwestern edge of the shock centered around (6°,
  -12°) was a dominant area of radio emission for the 2 hr of simulation
  data out to 20 solar radii.

Title: Simulating Solar Maximum Conditions Using the Alfvén Wave
    Solar Atmosphere Model (AWSoM)
Authors: Sachdeva, Nishtha; Tóth, Gábor; Manchester, Ward B.; van
   der Holst, Bart; Huang, Zhenguang; Sokolov, Igor V.; Zhao, Lulu;
   Shidi, Qusai Al; Chen, Yuxi; Gombosi, Tamas I.; Henney, Carl J.;
   Lloveras, Diego G.; Vásquez, Alberto M.
Bibcode: 2021ApJ...923..176S
Altcode:
  To simulate solar coronal mass ejections (CMEs) and predict their
  time of arrival and geomagnetic impact, it is important to accurately
  model the background solar wind conditions in which CMEs propagate. We
  use the Alfvén Wave Solar atmosphere Model (AWSoM) within the the
  Space Weather Modeling Framework to simulate solar maximum conditions
  during two Carrington rotations and produce solar wind background
  conditions comparable to the observations. We describe the inner
  boundary conditions for AWSoM using the ADAPT global magnetic maps
  and validate the simulated results with EUV observations in the low
  corona and measured plasma parameters at L1 as well as at the position
  of the Solar Terrestrial Relations Observatory spacecraft. This
  work complements our prior AWSoM validation study for solar minimum
  conditions and shows that during periods of higher magnetic activity,
  AWSoM can reproduce the solar plasma conditions (using properly
  adjusted photospheric Poynting flux) suitable for providing proper
  initial conditions for launching CMEs.

Title: Predicting the Background Solar Wind for Solar Maximum
    Conditions with the Alfven Wave Solar atmosphere model (AWSoM)
Authors: Sachdeva, Nishtha; Toth, Gabor; Manchester, Ward; van der
   Holst, Bart; Huang, Zhenguang; Sokolov, Igor; Zhao, Lulu; Al Shidi,
   Qusai; Chen, Yuxi; Gombosi, Tamas; Henney, Carl
Bibcode: 2021AGUFMSH45D2396S
Altcode:
  For physics-based simulations of the coronal mass ejections (CMEs)
  it is essential to start with realistic background solar wind
  conditions. To achieve this goal, we use the 3D extended MHD Alfven
  Wave Solar atmosphere Model (AWSoM) to simulate the background plasma
  environment during the magnetically active phase of solar cycle 24 and
  validate the results with in situ and remote observations. Representing
  the solar maximum conditions by two Carrington Rotations, we use the
  ADAPT-HMI photospheric magnetic-field maps to drive AWSoM and simulate
  the solar wind from the low corona to Earths orbit. We compare the AWSoM
  predicted solar wind with EUV observations near the Sun as well as with
  observed plasma and magnetic field parameters at L1 and at the STEREO
  spacecraft location. We find that the optimal value for the Poynting
  flux parameter of the model depends on the solar activity: for solar
  maximum it has to be reduced by about a factor of two compared to the
  solar minimum. Using properly adjusted Poynting flux parameters for the
  solar maximum period results in a reasonable match with observations
  for which quantitative comparisons show small margins of error. These
  provide a reasonably accurate background solar wind into which a CME
  will be launched.

Title: A Numerical View of Stellar Coronal Mass Ejections and
    Exoplanet Habitability
Authors: Alvarado Gomez, Julian; Drake, Jeremy; Cohen, Ofer;
   Fraschetti, Federico; Garraffo, Cecilia; Poppenhaeger, Katja; Yadav,
   Rakesh; Manchester, Ward
Bibcode: 2021AGUFM.U43B..09A
Altcode:
  Coronal mass ejections (CMEs) are more energetic than any other class
  of solar phenomena. They arise from the rapid release of up to 1033
  erg of magnetic energy mainly in the form of particle acceleration and
  bulk plasma motion. Their stellar counterparts, presumably involving
  much larger energies, are expected to play a fundamental role in
  shaping the environmental conditions around low-mass stars, in some
  cases perhaps with catastrophic consequences for planetary systems
  due to processes such as atmospheric erosion and depletion. Despite
  their importance, the direct observational evidence for stellar CMEs
  is almost non-existent. In this way, numerical simulations constitute
  extremely valuable tools to shed some light on eruptive behaviour in
  the stellar regime. In this talk, I will review recent results obtained
  from realistic modelling of CMEs in active stars, highlighting their
  key role in the interpretation of currently available observational
  constraints. This includes studies performed on M-dwarf stars,
  focusing on how emerging signatures in different wavelengths related
  to these events vary as a function of the magnetic properties of
  the star. Finally, the implications and relevance of these numerical
  results will be discussed in the context of future characterisation
  of host star-exoplanet systems.

Title: What sustained multi-disciplinary research can achieve:
    The space weather modeling framework
Authors: Gombosi, Tamas I.; Chen, Yuxi; Glocer, Alex; Huang, Zhenguang;
   Jia, Xianzhe; Liemohn, Michael W.; Manchester, Ward B.; Pulkkinen,
   Tuija; Sachdeva, Nishtha; Al Shidi, Qusai; Sokolov, Igor V.; Szente,
   Judit; Tenishev, Valeriy; Toth, Gabor; van der Holst, Bart; Welling,
   Daniel T.; Zhao, Lulu; Zou, Shasha
Bibcode: 2021JSWSC..11...42G
Altcode: 2021arXiv210513227G
  Magnetohydrodynamics (MHD)-based global space weather models have
  mostly been developed and maintained at academic institutions. While
  the "free spirit" approach of academia enables the rapid emergence
  and testing of new ideas and methods, the lack of long-term stability
  and support makes this arrangement very challenging. This paper
  describes a successful example of a university-based group, the Center
  of Space Environment Modeling (CSEM) at the University of Michigan,
  that developed and maintained the Space Weather Modeling Framework
  (SWMF) and its core element, the BATS-R-US extended MHD code. It took
  a quarter of a century to develop this capability and reach its present
  level of maturity that makes it suitable for research use by the space
  physics community through the Community Coordinated Modeling Center
  (CCMC) as well as operational use by the NOAA Space Weather Prediction
  Center (SWPC).

Title: Localizing the Source of Type II Emission Around a CME with
    the Sun Radio Interferometer Space Experiment (SunRISE) and MHD
    Simulations
Authors: Hegedus, Alexander; Manchester, Ward; Kasper, Justin; Lazio,
   Joseph; Romero-Wolf, Andrew
Bibcode: 2021EGUGA..23.6435H
Altcode:
  The Earth"s Ionosphere limits radio measurements on its surface,
  blocking out any radiation below 10 MHz. Valuable insight into many
  astrophysical processes could be gained by having a radio interferometer
  in space to image the low frequency window, which has never been
  achieved. One application for such a system is observing type II
  bursts that track solar energetic particle acceleration occurring at
  Coronal Mass Ejection (CME)-driven shocks. This is one of the primary
  science targets for SunRISE, a 6 CubeSat interferometer to circle
  the Earth in a GEO graveyard orbit. SunRISE is a NASA Heliophysics
  Mission of Opportunity that began Phase B (Formulation) in June 2020,
  and plans to launch for a 12-month mission in mid-2023. In this work
  we present an update to the data processing and science analysis
  pipeline for SunRISE and evaluate its performance in localizing type
  II bursts around a simulated CME.To create realistic virtual type II
  input data, we employ a 2-temperature MHD simulation of the May 13th
  2005 CME event, and superimpose realistic radio emission models on the
  CME-driven shock front, and propagate the signal through the simulated
  array. Data cuts based on different plasma parameter thresholds
  (e.g. de Hoffman-Teller velocity and angle between shock normal and
  the upstream magnetic field) are tested to get the best match to the
  true recorded emission. This model type II emission is then fed to the
  SunRISE data processing pipeline to ensure that the array can localize
  the emission. We include realistic thermal noise dominated by the
  galactic background at these low frequencies, as well as new sources
  of phase noise from positional uncertainty of each spacecraft. We test
  simulated trajectories of SunRISE and image what the array recovers,
  comparing it to the virtual input, finding that SunRISE can resolve
  the source of type II emission to within its prescribed goal of 1/3
  the CME width. This shows that SunRISE will significantly advance the
  scientific community"s understanding of type II burst generation, and
  consequently, acceleration of solar energetic particles at CMEs. This
  unique combination of SunRISE observations and MHD recreations of
  space weather events will allow an unprecedented look into the plasma
  parameters important for these processes.

Title: Eruptive events in active stars: Lessons from numerical
    simulations
Authors: Alvarado Gomez, J.; Drake, J. J.; Fraschetti, F.; Cohen,
   O.; Poppenhaeger, K.; Garraffo, C.; Moschou, S.; Vocks, C.; Yadav,
   R.; Manchester, W.
Bibcode: 2021BAAS...53c0401A
Altcode:
  Flares and coronal mass ejections (CMEs) are more energetic than any
  other class of solar phenomena. These events involve the rapid release
  of up to 10<SUP>33</SUP> erg of magnetic energy in the form of particle
  acceleration, heating, radiation, and bulk plasma motion. Displaying
  much larger energies, their stellar counterparts are expected to play
  a fundamental role in shaping the evolution of activity and rotation,
  as well as the environmental conditions around low-mass stars. While
  flares are now routinely detected in multi-wavelength observations
  across all spectral types and ages, direct evidence for stellar CMEs
  is almost non-existent. In this context, numerical simulations provide
  a valuable pathway to shed some light on the eruptive behavior in the
  stellar regime. In this talk, I will review recent results obtained
  from realistic modeling of CMEs in active stars. Emphasis will be
  given to M dwarfs, focusing on possible observable coronal signatures
  of these events using next-generation X-ray missions. Furthermore, an
  explanation for the lack of Type II radio bursts from CMEs in active
  M dwarfs despite their frequent flaring will be discussed. Finally,
  the implications and relevance of these numerical results will
  be considered in the context of future characterization of host
  star-exoplanet systems.

Title: Threaded-field-line Model for the Low Solar Corona Powered
    by the Alfvén Wave Turbulence
Authors: Sokolov, Igor V.; Holst, Bart van der; Manchester, Ward B.;
   Su Ozturk, Doga Can; Szente, Judit; Taktakishvili, Aleksandre; Tóth,
   Gábor; Jin, Meng; Gombosi, Tamas I.
Bibcode: 2021ApJ...908..172S
Altcode:
  We present an updated global model of the solar corona, including the
  transition region. We simulate the realistic three-dimensional (3D)
  magnetic field using the data from the photospheric magnetic field
  measurements and assume the magnetohydrodynamic (MHD) Alfvén wave
  turbulence and its nonlinear dissipation to be the only source for
  heating the coronal plasma and driving the solar wind. In closed-field
  regions, the dissipation efficiency in a balanced turbulence is
  enhanced. In the coronal holes, we account for a reflection of the
  outward-propagating waves, which is accompanied by the generation
  of weaker counterpropagating waves. The nonlinear cascade rate
  degrades in strongly imbalanced turbulence, thus resulting in colder
  coronal holes. The distinctive feature of the presented model is the
  description of the low corona as almost-steady-state low-beta plasma
  motion and heat flux transfer along the magnetic field lines. We trace
  the magnetic field lines through each grid point of the lower boundary
  of the global corona model, chosen at some heliocentric distance,
  R = R<SUB>b</SUB> ∼ 1.1R<SUB>⊙</SUB>, well above the transition
  region. One can readily solve the plasma parameters along the magnetic
  field line from 1D equations for the plasma motion and heat transport
  together with the Alfvén wave propagation, which adequately describe
  the physics within the heliocentric distance range R<SUB>⊙</SUB>
  &lt; R &lt; R<SUB>b</SUB>, in the low solar corona. By interfacing
  this threaded-field-line model with the full MHD global corona model
  at r = R<SUB>b</SUB>, we find the global solution and achieve a
  faster-than-real-time performance of the model on ∼200 cores.

Title: Probing the Puzzle of Fermi Long-Duration Gamma-Ray Flares
    by Data-driven Global MHD Simulations
Authors: Jin, M.; Petrosian, V.; Liu, W.; Nitta, N.; Omodei, N.;
   Effenberger, F.; Li, G.; Pesce-Rollins, M.; Allafort, A.; Manchester,
   W.
Bibcode: 2020AGUFMSH008..03J
Altcode:
  With the ever growing number of long-duration, &gt;100 MeV gamma-ray
  solar flares observed by Fermi/LAT, it poses a puzzle on the underlying
  particle acceleration and transport mechanisms. Further challenges
  come from (i) recent detection of gamma-rays in behind-the-limb (BTL)
  flares (e.g., the 2014 September 1 event), in which the gamma-ray
  emission region is located away from the BTL flare site by tens of
  degrees in heliographic longitude, and (ii) migration of gamma-ray
  emission centroids on the solar disk hours past the impulsive phase
  (e.g., the 2012 March 7 event). Most of the long-duration events are
  associated with fast CMEs, it is thus necessary to understand the role
  of CMEs and CME-driven shocks in these events. To probe this puzzle,
  we perform data-driven, global magnetohydrodynamics simulations of CMEs
  associated with the long-duration gamma-ray flares. We investigate
  the magnetic connectivity and evolution of the CME-driven shocks,
  and their relationship, in both space and time, with the observed
  gamma-ray emission. Specifically, we derive and track the time-varying
  shock parameters over the area that is magnetically connected to the
  gamma-ray emission region. Based on the modeling results, we discuss
  the causes of Fermi long-duration gamma-ray events. In particular, we
  address the possibility of CME shock-accelerated particles traveling
  back to the Sun to produce gamma-rays, a scenario that bears potentially
  paradigm-shifting implications on particle acceleration and transport
  in solar eruptive events including flares and CMEs.

Title: Three-Dimensional Tomographic Reconstruction and MHD Modeling
of the Solar Corona and Wind: WHPI Campaign Rotations CR-2219
    and CR-2223
Authors: Lloveras, D.; Vásquez, A. M.; Nuevo, F.; Sachdeva, N.;
   Manchester, W.; van der Holst, B.; Frazin, R. A.; Lamy, P.; Wojak, J.
Bibcode: 2020AGUFMSH021..07L
Altcode:
  Accurate prediction of space weather conditions requires
  state-of-the-art three-dimensional (3D) magnetohydrodynamic (MHD)
  models, which need to be validated with observational data. The recent
  deep minimum of solar activity, between solar cycles 24 and 25, renews
  the opportunity to study the Sun-Earth connection under the simplest
  solar and space environmental conditions. The international Whole
  Heliosphere and Planetary Interactions (WHPI) initiative aims at this
  specific purpose. In this work, we study two WHPI campaign periods,
  the July 2019 total solar eclipse Carrington rotation (CR)-2019, and
  the Parker Solar Probe and STEREO-A closest approach CR-2223. Based
  on narrowband EUV data provided by the SDO/AIA instrument we carry
  out tomographic reconstruction of the coronal electron density
  and temperature in the range of heliocentric heights r ≤ 1.25
  R<SUB>sun</SUB>. Based on visible light coronagraph data provided by
  the SoHO/LASCO-C2 instrument we carry out tomographic reconstruction of
  the coronal electron density and in the range of heliocentric heights
  ≈ 2.5-6.0 R<SUB>sun</SUB>. Applying ADAPT-GONG synoptic magnetograms
  as boundary conditions, we use the Alfven Wave Solar Model (AWSoM)
  to simulate the corona and solar wind for these time periods. We
  study the capability of the 3D-MHD model to reproduce the tomographic
  reconstructions in both closed and open coronal magnetic structures. In
  coronal holes in particular, we investigate the correlation between
  the reconstructed 3D distribution of the thermodynamical properties
  in the low corona and the 3D distribution of the physical parameters
  of the terminal solar wind of the model, discriminating its fast and
  slow components

Title: Simulating Solar Maximum Conditions with the Alfven Wave
    Solar Atmosphere Model (AWSoM)
Authors: Sachdeva, N.; van der Holst, B.; Toth, G.; Manchester, W.;
   Sokolov, I.
Bibcode: 2020AGUFMSH0290015S
Altcode:
  The Alfven Wave Solar atmosphere Model (AWSoM) within the Space Weather
  Modeling Framework (SWMF) is a physics-based solar corona model
  that solves magnetohydrodynamic (MHD) equations along with Alfven
  wave turbulence, radiative cooling and heat conduction. The Alfven
  wave pressure and dissipation account for solar wind acceleration and
  heating. AWSoM extends from the upper chromosphere up to 1 AU and beyond
  and includes the description of electron temperature and perpendicular
  and parallel proton temperature. AWSoM is driven by observations of the
  photospheric magnetic field, which are applied at the inner boundary. In
  this study, we use the ADAPT (Air Force Data Assimilative Photospheric
  Flux Transport) synchronic maps to drive our solar corona model. The
  ADAPT model uses observations of the solar photospheric magnetic field
  to produce an ensemble of magnetic field maps using a flux-transport
  model and data assimilation. We simulate solar maximum conditions using
  AWSoM and compare the results with SDO/AIA observations in the low
  corona and observations of solar wind density, speed and magnetic field
  at 1 AU (OMNI data). The background solar wind derived from our model
  provides the plasma environment into which Coronal Mass Ejections (CMEs)
  can be launched. We use the Gibson-Low Flux Rope model to initiate a
  CME and propagate it into the inner heliosphere. We validate the CME
  simulation by comparing the results with remote as well as in-situ
  observations from SOHO, SDO, STEREO, and WIND.

Title: NextGen Space Weather Modeling Framework Using Physics,
    Data Assimilation, Uncertainty Quantification and GPUs
Authors: Toth, G.; Zou, S.; Chen, Y.; Huan, X.; van der Holst, B.;
   Manchester, W.; Liemohn, M. W.; Chen, Y.; Huang, Z.; Gaenko, A.
Bibcode: 2020AGUFMSM015..05T
Altcode:
  We have been recently awarded a major NSF/NASA grant from the SWQU
  program to develop the NextGen Space Weather Modeling Framework that
  will employ computational models from the surface of the Sun to the
  surface of Earth in combination with assimilation of observational
  data to provide optimal probabilistic space weather forecasting. The
  model will run efficiently on the next generation of supercomputers
  to predict space weather about one day or more before the impact
  occurs. The new project will concentrate on forecasting major space
  weather events generated by coronal mass ejections (CMEs). Current space
  weather prediction tools employ first-principles and/or empirical
  models. While these provide useful information, their accuracy,
  reliability and forecast window need major improvements. Data
  assimilation has the potential to significantly improve model
  performance, as it has been successfully done in terrestrial weather
  forecast. To allow for the sparsity of satellite observations, however,
  a different data assimilation method will be employed. The new model
  will start from the Sun with an ensemble of simulations that span
  the uncertain observational and model parameters. Using real time and
  past observations, the model will strategically down-select to a high
  performing subset. Next, the down-selected ensemble will be extended by
  varying uncertain parameters and the simulation continued to the next
  data assimilation point. The final ensemble will provide a probabilistic
  forecast of the space weather impacts. While the concept is simple,
  finding the optimal algorithm that produces the best prediction with
  minimal uncertainty is a complex and very challenging task that requires
  developing, implementing and perfecting novel data assimilation and
  uncertainty quantification methods. To make these ensemble simulations
  run faster than real time, the most expensive parts of the model
  need to run efficiently on the current and future supercomputers,
  which employ graphical processing units (GPUs) in addition to the
  traditional multi-core CPUs. The main product of this project will be
  the Michigan Sun-To-Earth Model with Quantified Uncertainty and Data
  Assimilation (MSTEM-QUDA) that will be made available to the space
  physics community with an open source license. We will describe the
  main concept of the project and our initial progress.

Title: Localizing the Source of Type II Emission Around a CME with
    the Sun Radio Interferometer Space Experiment (SunRISE)
Authors: Hegedus, A. M.; Kasper, J. C.; Manchester, W.; Lazio, J.;
   Romero-Wolf, A.
Bibcode: 2020AGUFMSH0090021H
Altcode:
  The Earth's Ionosphere limits radio measurements on its surface,
  blocking out any radiation below 10 MHz. Valuable insight into many
  astrophysical processes could be gained by having a radio interferometer
  in space to image the low frequency window, which has never been
  achieved. One application for such a system is observing type II bursts
  that track solar energetic particle acceleration occurring at Coronal
  Mass Ejection (CME)-driven shocks. This is one of the primary science
  targets for SunRISE, a 6 CubeSat interferometer to circle the Earth
  in a GEO graveyard orbit. SunRISE is a NASA Heliophysics Mission of
  Opportunity that began Phase B (Formulation) in June 2020, and plans to
  launch for a 12-month mission in mid-2023. In this work we present an
  update to the data processing and science analysis pipeline for SunRISE
  and evaluate its performance in localizing type II bursts around a
  simulated CME. <P />To create realistic virtual type II input data,
  we employ a 2-temperature MHD simulation of the May 13<SUP>th</SUP>
  2005 CME event, and superimpose realistic radio emission models on the
  CME-driven shock front, and propagate the signal through the simulated
  array. Data cuts based on different plasma parameter thresholds (e.g. de
  Hoffman-Teller velocity and angle between shock normal and the upstream
  magnetic field) are tested to get the best match to the true recorded
  emission. We take into account sources of angular scattering of the
  emission such as coronal turbulence. This model type II emission
  is then fed to the SunRISE data processing pipeline to ensure that
  the array can localize the emission. We include realistic thermal
  noise dominated by the galactic background at these low frequencies,
  as well as new sources of phase noise from positional uncertainty of
  each spacecraft. We test simulated trajectories of SunRISE and image
  what the array recovers, comparing it to the virtual input, finding
  that SunRISE can resolve the source of type II emission to within
  its prescribed goal of 1/3 the CME width. This shows that SunRISE
  will significantly advance the scientific community's understanding
  of type II burst generation, and consequently, acceleration of solar
  energetic particles at CMEs. <P />Complementary abstracts for SunRISE
  are presented by J. Kasper, A. Romero-Wolf, and J. Lazio.

Title: Applying Machine Learning \to Understanding the Physical
    Processes of Solar Flare Onset
Authors: Manchester, W.; Sun, H.; Chen, Y.; Liu, Y.; Jin, M.
Bibcode: 2020AGUFMNG0040005M
Altcode:
  We apply deep learning algorithms (Long Short Term Memory -LSTM) to
  train binary strong/weak classification models using active region
  parameters provided in HMI/Space-Weather HMI-Active Region Patch
  (SHARP) data files. We identify 35 active regions which show a sudden
  transition of the prediction score (above 0.7) indicating the likelihood
  of an M/X class flare several hours before the event. We examine the
  HMI vector magnetogram data for these events to determine if there
  are common circumstances and physical processes responsible for the
  magnetic energy and magnetic shear that informs the predictions. We
  further examine extrapolated nonlinear force-free coronal fields and
  Atmospheric Imaging Assembly (AIA) images to determine the structure
  of the coronal field and the associated electric currents and free
  magnetic energy increase prior to the flaring events. In many cases,
  we find development of strong horizontal fields running nearly parallel
  to the polarity inversion line to be a precursor to the flaring events.

Title: Comparing the best ADAPT realizations from WSA, AWSoM and
    AWSoM-R
Authors: Huang, Z.; Sokolov, I.; van der Holst, B.; Toth, G.; Arge,
   C. N.; Sachdeva, N.; Jones, S. I.; Manchester, W.; Gombosi, T. I.
Bibcode: 2020AGUFMSH0290028H
Altcode:
  Solar corona models are typically driven by global photospheric
  magnetic field maps assembled from magnetograms. Magnetic field maps
  derived from different magnetogram sources (e.g. MDI, GONG, etc)
  can produce different results when used as boundary conditions. One
  of the commonly used synchronic maps is provided by the ADAPT (Air
  Force Data Assimilative Photospheric Flux Transport) model, which
  makes use of a flux transport model to evolve the regions where there
  are no observations. The ADAPT model uses the ensemble least-squares
  data assimilation method that account for model and observational
  uncertainties and provides 12 different realizations for a given
  moment in time. Previous studies have shown the same solar corona
  model running with 12 different realizations also provide different
  predicted solar wind values at 1 AU. In this presentation, we will
  use the ADAPT maps to drive the WSA (Wang-Sheeley-Arge) model, the
  AWSoM (Alfven-Wave driven Solar atmosphere Model) and the AWSoM-R
  (Alfven-Wave driven Solar atmosphere Model - Realtime) model. The
  coronal portion of the WSA model makes use of the coupled potential
  field source surface and Schatten current sheet models to derive the
  global coronal magnetic field from global maps of the photospheric
  field. The model then applies empirical formulas to specify the solar
  wind at the outer coronal boundary and a 1D kinematic model to predict
  solar wind speed and interplanetary magnetic polarity anywhere in
  the inner heliosphere. AWSoM is a physics-based model solving the
  MHD equations together with radiative cooling, heat conduction and a
  phenomenological Alfven wave turbulence and dissipation model including
  wave reflection (proportional to the Alfvén speed gradients) and
  turbulent dissipation from the chromosphere to the heliosphere. The
  AWSoM-R model uses 1-D field line threads to simulate the region in
  the lower chromosphere to speed up the simulations. We will compare
  the predicted solar wind values at 1 AU with observations and use the
  WSA Prediction Metric developed at NASA Goddard Space Flight Center to
  select the best ADAPT map realization(s) for the three models. We will
  investigate whether we can improve the prediction capability of the
  complex physics-based models like AWSoM and AWSoM-R using the insight
  gained from the inexpensive empirical WSA model.

Title: Solar Flare Intensity Prediction With Machine Learning Models
Authors: Jiao, Zhenbang; Sun, Hu; Wang, Xiantong; Manchester, Ward;
   Gombosi, Tamas; Hero, Alfred; Chen, Yang
Bibcode: 2020SpWea..1802440J
Altcode: 2019arXiv191206120J
  We develop a mixed long short-term memory (LSTM) regression model to
  predict the maximum solar flare intensity within a 24-hr time window
  0-24, 6-30, 12-36, and 24-48 hr ahead of time using 6, 12, 24, and
  48 hr of data (predictors) for each Helioseismic and Magnetic Imager
  (HMI) Active Region Patch (HARP). The model makes use of (1) the
  Space-Weather HMI Active Region Patch (SHARP) parameters as predictors
  and (2) the exact flare intensities instead of class labels recorded
  in the Geostationary Operational Environmental Satellites (GOES) data
  set, which serves as the source of the response variables. Compared
  to solar flare classification, the model offers us more detailed
  information about the exact maximum flux level, that is, intensity,
  for each occurrence of a flare. We also consider classification
  models built on top of the regression model and obtain better results
  in solar flare classifications as compared to Chen et al. (2019, <A
  href="https://doi.org/10.1029/2019SW002214">https://doi.org/10.1029/2019SW002214</A>).
  Our results suggest that the most efficient time period for predicting
  the solar activity is within 24 hr before the prediction time using
  the SHARP parameters and the LSTM model.

Title: Thermodynamic Structure of the Solar Corona: Tomographic
    Reconstructions and MHD Modeling
Authors: Lloveras, Diego G.; Vásquez, Alberto M.; Nuevo, Federico
   A.; Mac Cormack, Cecilia; Sachdeva, Nishtha; Manchester, Ward; Van
   der Holst, Bartholomeus; Frazin, Richard A.
Bibcode: 2020SoPh..295...76L
Altcode: 2020arXiv200406815L
  We carry out a study of the global three-dimensional (3D) structure of
  the electron density and temperature of the quiescent inner solar corona
  (r &lt;1.25 R<SUB>⊙</SUB>) by means of tomographic reconstructions and
  magnetohydrodynamic simulations. We use differential emission measure
  tomography (DEMT) and the Alfvén Wave Solar Model (AWSoM), in their
  latest versions. Two target rotations were selected from the solar
  minimum between Solar Cycles (SCs) 23 and 24 and the declining phase
  of SC 24. We report in quantitative detail on the 3D thermodynamic
  structure of the core and outer layers of the streamer belt, and
  of the high latitude coronal holes (CH), as revealed by the DEMT
  analysis. We report on the presence of two types of structures within
  the streamer belt, loops with temperature decreasing/increasing with
  height (dubbed down/up loops), as reported first in previous DEMT
  studies. We also estimate the heating energy flux required at the
  coronal base to keep these structures stable, found to be of order
  10<SUP>5</SUP>ergcm−<SUP>2</SUP>s−<SUP>1</SUP>, consistently with
  previous DEMT and spectroscopic studies. We discuss how these findings
  are consistent with coronal dissipation of Alfvén waves. We compare
  the 3D results of DEMT and AWSoM in distinct magnetic structures. We
  show that the agreement between the products of both techniques is the
  best so far, with an overall agreement ≲20 % , depending on the target
  rotation and the specific coronal region. In its current implementation
  the ASWsoM model cannot reproduce down loops though. Also, in the
  source region of the fast and slow components of the solar wind,
  the electron density of the AWSoM model increases with latitude,
  opposite to the trend observed in DEMT reconstructions.

Title: Tuning the Exospace Weather Radio for Stellar Coronal Mass
    Ejections
Authors: Alvarado-Gómez, Julián D.; Drake, Jeremy J.; Fraschetti,
   Federico; Garraffo, Cecilia; Cohen, Ofer; Vocks, Christian;
   Poppenhäger, Katja; Moschou, Sofia P.; Yadav, Rakesh K.; Manchester,
   Ward B., IV
Bibcode: 2020ApJ...895...47A
Altcode: 2020arXiv200405379A
  Coronal mass ejections (CMEs) on stars other than the Sun have proven
  very difficult to detect. One promising pathway lies in the detection
  of type II radio bursts. Their appearance and distinctive properties
  are associated with the development of an outward propagating CME-driven
  shock. However, dedicated radio searches have not been able to identify
  these transient features in other stars. Large Alfvén speeds and
  the magnetic suppression of CMEs in active stars have been proposed to
  render stellar eruptions "radio-quiet." Employing 3D magnetohydrodynamic
  simulations, we study the distribution of the coronal Alfvén speed,
  focusing on two cases representative of a young Sun-like star and a
  mid-activity M-dwarf (Proxima Centauri). These results are compared with
  a standard solar simulation and used to characterize the shock-prone
  regions in the stellar corona and wind. Furthermore, using a flux-rope
  eruption model, we drive realistic CME events within our M-dwarf
  simulation. We consider eruptions with different energies to probe the
  regimes of weak and partial CME magnetic confinement. While these CMEs
  are able to generate shocks in the corona, those are pushed much farther
  out compared to their solar counterparts. This drastically reduces
  the resulting type II radio burst frequencies down to the ionospheric
  cutoff, which impedes their detection with ground-based instrumentation.

Title: Predicting Solar Flares with Machine Learning: Investigating
    Solar Cycle Dependence
Authors: Wang, Xiantong; Chen, Yang; Toth, Gabor; Manchester, Ward
   B.; Gombosi, Tamas I.; Hero, Alfred O.; Jiao, Zhenbang; Sun, Hu; Jin,
   Meng; Liu, Yang
Bibcode: 2020ApJ...895....3W
Altcode: 2019arXiv191200502W
  A deep learning network, long short-term memory (LSTM), is used to
  predict whether an active region (AR) will produce a flare of class
  Γ in the next 24 hr. We consider Γ to be ≥M (strong flare), ≥C
  (medium flare), and ≥A (any flare) class. The essence of using LSTM,
  which is a recurrent neural network, is its ability to capture temporal
  information on the data samples. The input features are time sequences
  of 20 magnetic parameters from the space weather Helioseismic and
  Magnetic Imager AR patches. We analyze ARs from 2010 June to 2018
  December and their associated flares identified in the Geostationary
  Operational Environmental Satellite X-ray flare catalogs. Our results
  produce skill scores consistent with recently published results using
  LSTMs and are better than the previous results using a single time
  input. The skill scores from the model show statistically significant
  variation when different years of data are chosen for training and
  testing. In particular, 2015-2018 have better true skill statistic and
  Heidke skill scores for predicting ≥C medium flares than 2011-2014,
  when the difference in flare occurrence rates is properly taken into
  account.

Title: Using a Higher-order Numerical Scheme to Study the Hall
    Magnetic Reconnection
Authors: Yang, Yun; Manchester, Ward B., IV
Bibcode: 2020ApJ...892...61Y
Altcode:
  We use our recently developed higher-order conservation element and
  solution element scheme to investigate the evolutionary process of
  Hall magnetic reconnection. The purpose of this paper is twofold: (1)
  to take advantage of higher-order numerical schemes to capture some fine
  structures very well with fewer grid points and reduced computational
  cost; (2) to develop a better understanding of the magnetic reconnection
  described by Hall MHD; as Birn et al. pointed out, the Hall effect
  is a critical ingredient in determining collisionless reconnection
  rates in the magnetosphere. The contributions of this paper mainly
  include the following: (1) we capture a two-step magnetic reconnection
  process and describe the formation mechanism; (2) the simulations
  show complex formation and interaction of magnetic islands and we
  provide the ways by which the magnetic islands form and disappear;
  (3) we find an oscillatory nature of the reconnection and the transfer
  of energy from magnetic field to kinetic energy and thermal energy;
  (4) we identify the merging process of the central magnetic island
  and the outflow region magnetic island.

Title: Implementation of the Sun Radio Interferometer Space Experiment
    (SunRISE) Mission Concept
Authors: Lazio, J.; Kasper, J. C.; Romero-Wolf, A.; Bastian, T.; Cohen,
   C.; Landi, E.; Manchester, W.; Hegedus, A. M.; Schwadron, N.; Sokolov,
   I.; Bain, H. M.; Cecconi, B.; Hallinan, G.; Krupar, V.; Maksimovic,
   M.; Moschou, S. P.; Zaslavsky, A.; Lux, J. P.; Neilsen, T. L.
Bibcode: 2019AGUFMSH31C3328L
Altcode:
  The Sun Radio Interferometer Space Experiment (SunRISE) would provide
  an entirely new view on particle acceleration and transport in the
  heliosphere by obtaining spatially and temporally resolved observations
  of Decametric-Hectometric (DH, &lt; 15 MHz) Type II and Type III
  radio bursts. <P />In order to obtain the required angular resolution,
  SunRISE would be a free-flying interferometer. Building on more than 50
  years of experience from ground-based very long baseline interferometry
  (VLBI), SunRISE would fly six small spacecraft in a supersynchronous
  geosynchronous orbit (GEO) in a passive formation. Their orbits
  are designed to keep them within approximately 6 km of each other. A
  space-based interferometer is required because most of the DH band does
  not penetrate the Earth's ionosphere, due to ionospheric absorption. <P
  />Each 6U spacecraft would carry only a single science radio designed
  to operate in the DH band. The radio would form spectra on-board,
  with pre-selected sub-bands identified for downlink. This science
  payload radio would be integrated into a Global Positioning System
  (GPS) receiver, allowing precise time to be measured on board the
  spacecraft as well. The spacecraft would be independent of each other,
  as is the practice for ground-based VLBI arrays. <P />On a regular
  basis, both science data and GPS timing would be downlinked. NASA's
  Deep Space Network antennas would be used for the downlink, with an
  efficient multiple spacecraft per aperture (MSPA) mode enabling the
  data from three spacecraft to be downlinked simultaneously. After orbit
  determination, the interferometric data processing would form images of
  Type II and Type III solar radio bursts and identify the locations of
  radio emission relative to the structures of CMEs. <P />SunRISE would
  leverage advances in software-defined radios, GPS navigation and timing,
  and small spacecraft technologies that have been demonstrated over
  the past few years. An Extended Phase A study of the SunRISE mission
  concept is scheduled to be completed in 2019 September. <P />Part
  of this research was carried out at the Jet Propulsion Laboratory,
  California Institute of Technology, under a contract with the National
  Aeronautics and Space Administration. Some of the information presented
  is pre-decisional and for planning and discussion purposes only.

Title: Global Magnetohydrodynamics Simulation of EUV Waves and Shocks
    from the X8.2 Eruptive Flare on 2017 September 10
Authors: Jin, M.; Liu, W.; Cheung, C. M. M.; Nitta, N.; DeRosa,
   M. L.; Manchester, W.; Ofman, L.; Downs, C.; Petrosian, V.; Omodei,
   N.; Moschou, S. P.; Sokolov, I.
Bibcode: 2019AGUFMSH32A..01J
Altcode:
  As one of the largest flare-CME eruptions during solar cycle 24, the
  2017 September 10 X8.2 flare event is associated with spectacular
  global EUV waves that transverse almost the entire visible solar
  disk, a CME with speed &gt; 3000 km/s, which is one of the fastest
  CMEs ever recorded, and &gt;100 MeV Gamma-ray emission lasting for
  more than 12 hours. All these unique observational features pose new
  challenge on current numerical models to reproduce the multi-wavelength
  observations. To take this challenge, we simulate the September 10
  event using a global MHD model (AWSoM: Alfven Wave Solar Model) within
  the Space Weather Modeling Framework and initiate CMEs by Gibson-Low
  flux rope. We assess several important observed and physical inputs
  (e.g., flux rope properties, polar magnetic field) in the model to
  better reproduce the multi-wavelength observations. We find that the
  simulated EUV wave morphology and kinematics are sensitive to the
  orientation of the initial flux rope introduced to the source active
  region. An orientation with the flux-rope axis in the north-south
  direction produces the best match to the observations, which suggests
  that EUV waves may potentially be used to constrain the flux-rope
  geometry for such limb or behind-the-limb eruptions that lack good
  magnetic field observations. By further combining with the white
  light and radio observations, we demonstrate the flux rope-corona
  interaction can greatly impact the early phase shock evolution (e.g.,
  geometry and shock parameters) therefore plays a significant role
  for particle acceleration near the Sun in this event. By propagating
  the CMEs into the heliosphere and beyond the Earth and Mars orbits, we
  compare the model results with the in-situ measurements and demonstrate
  the importance of input polar magnetic field on the realistic CME
  modeling therefore space weather forecasting.

Title: Asymmetries in the Martian system
Authors: Regoli, L.; Bougher, S. W.; Manchester, W.
Bibcode: 2019AGUFMSM33D3229R
Altcode:
  The induced Martian magnetosphere is a particularly complex system due
  to different dynamic properties that are part of the system. The lack
  of a global dynamo and the presence of a relatively tenuous atmosphere
  causes the induced magnetosphere to be significantly smaller than
  a formal magnetosphere and the boundaries are largely affected by
  changes in the upstream conditions. In addition, the presence of strong
  localized magnetic fields in the southern hemisphere, commonly referred
  to as crustal fields, adds an extra level of complexity, with changes in
  the pressure balance through changes in the local magnetic pressure and
  localized reconnection constantly changing the magnetic topology of the
  induced magnetosphere. This introduces a strong north/south asymmetry
  in the system that affects the location of different boundaries as
  well as the ionospheric escape, by changing the altitude of the main
  ionospheric peak. The dynamical heating of the atmosphere by the solar
  radiation also induces asymmetries in the atmospheric densities, which
  in turn affect the ion production and subsequent ionospheric escape as
  well. These can be north/south asymmetries (depending on the season)
  but also dawn/dusk, creating a particular escape pattern that can
  be observed in simulations under controlled conditions. We present
  results from a coupled set of models with changing parameters based on
  a well-defined parameter space in order to study their effect on the
  asymmetries present in the Martian system. These parameters include
  interplanetary magnetic field (IMF) orientation, solar wind dynamics
  pressure, atmospheric dynamics and location of the crustal fields.

Title: The Sun Radio Interferometer Space Experiment (SunRISE)
    Mission Concept
Authors: Kasper, J. C.; Lazio, J.; Romero-Wolf, A.; Bain, H. M.;
   Bastian, T.; Cohen, C.; Landi, E.; Manchester, W.; Hegedus, A. M.;
   Schwadron, N.; Sokolov, I.; Cecconi, B.; Hallinan, G.; Krupar, V.;
   Maksimovic, M.; Moschou, S. P.; Zaslavsky, A.; Lux, J. P.; Neilsen,
   T. L.
Bibcode: 2019AGUFMSH33A..02K
Altcode:
  The Sun Radio Interferometer Space Experiment (SunRISE) would provide
  an entirely new view on particle acceleration and transport in the
  inner heliosphere by obtaining spatially and temporally resolved
  observations of solar Decametric-Hectometric (DH, &lt; 15 MHz) radio
  bursts. These bursts are produced by electrons energized near expanding
  CMEs (Type II) and released by solar flares (Type III). SunRISE would
  track DH bursts from 2 R<SUB>S</SUB> to 20 R<SUB>S</SUB> in order to
  achieve two science objectives. The first objective is to discriminate
  competing hypotheses for the source mechanism of CME-associated SEPs by
  measuring the location of Type II bursts relative to expanding CMEs. By
  locating Type II emission relative to the overall structure of CMEs,
  SunRISE would reveal where particle acceleration occurs and determine
  if specific properties of CMEs lead to DH bursts. The second objective
  is to determine if a broad magnetic connection between active regions
  and interplanetary space is responsible for the wide longitudinal extent
  of some SEPs by imaging the field lines traced by Type III bursts from
  active regions through the corona. By tracing the radio emission from
  energetic electrons as they travel along magnetic field lines, SunRISE
  would reveal the field line topology, and its time variation, from
  active regions into interplanetary space. <P />SunRISE would consist
  of six 6U small spacecraft in a supersynchronous geosynchronous orbit
  (GEO) in a passive formation. Forming a synthetic aperture and observing
  at frequencies that cannot be observed on Earth due to ionospheric
  absorption, SunRISE would leverage advances in software-defined radios,
  GPS navigation and timing, and small spacecraft technologies. These
  advances have been flown over the past few years, making this concept
  finally affordable and low-risk. <P />An Extended Phase A study
  of the SunRISE mission concept is scheduled to be completed in 2019
  September. This paper presents a summary of the concept study. <P />Part
  of this research was carried out at the Jet Propulsion Laboratory,
  California Institute of Technology, under a contract with the National
  Aeronautics and Space Administration. Some of the information presented
  is pre-decisional and for planning and discussion purposes only.

Title: Predicting Solar Flares using Time Sequence Based Machine
    Learning Models
Authors: Wang, X.; Toth, G.; Chen, Y.; Manchester, W.; Jiao, Z.; Sun,
   H.; Sun, Z.; Hero, A. O.; Gombosi, T. I.
Bibcode: 2019AGUFMSH34A..03W
Altcode:
  In the last few years machine learning methods are becoming popular
  for predicting solar flares. We use the Space-weather HMI Active Region
  Patches (SHARP) dataset to analyze thousands of active regions' magnetic
  field and derived parameters (total unsigned flux, free magnetic
  energy, etc) using various machine learning algorithms. In this work
  we first use the SHARP summary parameters to predict the maximum flare
  intensity in a certain time window through a Long Short-Term Memory
  (LSTM) algorithm, which is a particular type of a recurrent neural
  network. The dataset we are using contains 3399 active regions from
  2010 to 2015. Furthermore, we will use the full vector magnetogram
  images to train a combined LSTM and feature extraction convolutional
  neural network (CNN). This approach allows capturing more detailed
  spatial-temporal features of the magnetic field. Our results show
  that using a time sequence to predict the maximum flare intensity can
  achieve a better Heidke Skill Score (HSS) than using a single frame
  as the input. The HSS for predicting the maximum flare class in the
  next 24 hours is about 0.35 for M/X flares and 0.55 for C/M/X flares.

Title: Interpreting LSTM Prediction on Solar Flare Eruption with
    Time-series Clustering
Authors: Sun, Hu; Manchester, Ward; Jiao, Zhenbang; Wang, Xiantong;
   Chen, Yang
Bibcode: 2019arXiv191212360S
Altcode:
  We conduct a post hoc analysis of solar flare predictions made by
  a Long Short Term Memory (LSTM) model employing data in the form of
  Space-weather HMI Active Region Patches (SHARP) parameters calculated
  from data in proximity to the magnetic polarity inversion line where the
  flares originate. We train the the LSTM model for binary classification
  to provide a prediction score for the probability of M/X class
  flares to occur in next hour. We then develop a dimension-reduction
  technique to reduce the dimensions of SHARP parameter (LSTM inputs) and
  demonstrate the different patterns of SHARP parameters corresponding
  to the transition from low to high prediction score. Our work shows
  that a subset of SHARP parameters contain the key signals that strong
  solar flare eruptions are imminent. The dynamics of these parameters
  have a highly uniform trajectory for many events whose LSTM prediction
  scores for M/X class flares transition from very low to very high. The
  results demonstrate the existence of a few threshold values of SHARP
  parameters that when surpassed indicate a high probability of the
  eruption of a strong flare. Our method has distilled the knowledge
  of solar flare eruption learnt by deep learning model and provides a
  more interpretable approximation, which provides physical insight to
  processes driving solar flares.

Title: Validation of the Alfvén Wave Solar Atmosphere Model (AWSoM)
    with Observations from the Low Corona to 1 au
Authors: Sachdeva, Nishtha; van der Holst, Bart; Manchester, Ward B.;
   Tóth, Gabor; Chen, Yuxi; Lloveras, Diego G.; Vásquez, Alberto M.;
   Lamy, Philippe; Wojak, Julien; Jackson, Bernard V.; Yu, Hsiu-Shan;
   Henney, Carl J.
Bibcode: 2019ApJ...887...83S
Altcode: 2019arXiv191008110S
  We perform a validation study of the latest version of the Alfvén
  Wave Solar atmosphere Model (AWSoM) within the Space Weather Modeling
  Framework. To do so, we compare the simulation results of the model
  with a comprehensive suite of observations for Carrington rotations
  representative of the solar minimum conditions extending from the
  solar corona to the heliosphere up to the Earth. In the low corona
  (r &lt; 1.25 {\text{}}{R}<SUB>⊙ </SUB>), we compare with EUV
  images from both Solar-Terrestrial Relations Observatory-A/EUVI
  and Solar Dynamics Observatory/Atmospheric Imaging Assembly and to
  three-dimensional (3D) tomographic reconstructions of the electron
  temperature and density based on these same data. We also compare the
  model to tomographic reconstructions of the electron density from
  Solar and Heliospheric Observatory/Large Angle and Spectrometric
  Coronagraph observations (2.55 &lt; r &lt; 6.0{\text{}}{R}<SUB>⊙
  </SUB>). In the heliosphere, we compare model predictions of solar wind
  speed with velocity reconstructions from InterPlanetary Scintillation
  observations. For comparison with observations near the Earth, we use
  OMNI data. Our results show that the improved AWSoM model performs
  well in quantitative agreement with the observations between the inner
  corona and 1 au. The model now reproduces the fast solar wind speed
  in the polar regions. Near the Earth, our model shows good agreement
  with observations of solar wind velocity, proton temperature, and
  density. AWSoM offers an extensive application to study the solar
  corona and larger heliosphere in concert with current and future solar
  missions as well as being well suited for space weather predictions.

Title: Nonequilibrium ionization effects on coronal plasma diagnostics
    and elemental abundance measurements
Authors: Shi, T.; Landi, E.; Manchester, W.
Bibcode: 2019AGUFMSH11C3402S
Altcode:
  Plasma diagnostics and elemental abundance measurements are crucial
  to help us understand the formation and dynamics of the solar
  wind. Here we use a theoretical solar wind model to study the effect
  of non-equilibrium ionization (NEI) on plasma diagnostic techniques
  applied to line intensities emitted by the fast solar wind. We find
  that NEI almost always changes the spectral line intensities with up to
  120% difference for the lighter elements and for higher charge states
  of Fe even below 1.5 solar radii (Rs). The measured plasma density,
  temperature, and differential emission measure (DEM) are only slightly
  affected by NEI. However, NEI significantly affects the first ionization
  potential (FIP) bias and abundance ratio measurements, producing up to
  a factor of 4 error at 1.5 Rs for Mg/Ne, Fe/S, and Ar/Fe ratios when
  assuming EI. We conclude that it is very important to consider the
  NEI effect when synthesizing spectral line intensities and measuring
  the FIP bias and elemental abundance.

Title: Improved AWSoM Modeling of the First Two PSP Encounters
Authors: van der Holst, B.; Chandran, B. D. G.; Borovikov, D.;
   Manchester, W.; Klein, K. G.; Kasper, J. C.; Case, A. W.; Korreck,
   K. E.; Larson, D. E.; Livi, R.; Stevens, M. L.; Whittlesey, P. L.;
   Bale, S.; Pulupa, M.; Malaspina, D.; Bonnell, J. W.; Harvey, P.;
   Goetz, K.; Dudok de Wit, T.; MacDowall, R. J.
Bibcode: 2019AGUFMSH13C3438V
Altcode:
  NASA's Parker Solar Probe (PSP) has collected data for the first two
  encounters. We have modeled the solar corona and inner heliosphere of
  these encounters using the Alfvén Wave Solar atmosphere Model (AWSoM,
  van der Holst et al. 2014) with GONG-ADAPT magnetograms. AWSoM allows
  us to interpret the PSP data in the context of coronal heating via
  low-frequency Alfvén wave turbulence with partial wave reflection due
  to Alfvén speed gradients. In van der Holst et al. (2019), we made
  predictions for the first encounter. In our new simulations we show
  how improved partitioning of the wave dissipation to the electron
  and anisotropic proton temperatures and better grid design result
  in significantly improved comparison with the PSP data. We also show
  the simulated distance of PSP to the heliospheric current sheet, the
  magnetic connectivity of PSP to the photosphere, and whether PSP was
  in the fast or slow wind.

Title: Solar Flare Classification and Prediction with Data Science
Authors: Chen, Y.; Manchester, W.; Gombosi, T. I.; Hero, A.; Wang, X.
Bibcode: 2019AGUFMSH34A..05C
Altcode:
  We present our machine learning efforts, which show great promise
  towards early predictions of solar flare events. First, we present
  a data pre-processing pipeline that is built to extract useful data
  from multiple sources -- Geostationary Operational Environmental
  Satellites (GOES) and Solar Dynamics Observatory (SDO)/Helioseismic
  and Magnetic Imager (HMI) and SDO/Atmospheric Imaging Assembly (AIA)
  -- to prepare inputs for machine learning algorithms. Second, we
  adopt deep learning algorithms to extract/select features from raw
  HMI and AIA data. Third, we train deep learning models that capture
  both the spatial and temporal information from HMI magnetogram data
  for strong/weak flare classification and for predictions of flare
  intensities. Fourth, we show that using the ML-derived features gives
  almost as good performance as using active region parameters provided
  in HMI/Space-Weather HMI-Active Region Patch (SHARP) data files,
  i.e. features manually constructed based on physical principles. Last,
  for our strong/weak flare classification model, case studies show a
  significant increase in the prediction score around 20 hours before
  strong solar flare events, which implies that early precursors appear
  at least 20 hours prior to the peak of a flare event.

Title: AWSoM Simulation of waves, turbulence and shocks associated
    with the September 10, 2014 CME/ICME
Authors: Manchester, W.; van der Holst, B.; Jin, M.; Kasper, J. C.
Bibcode: 2019AGUFMSH41A..04M
Altcode:
  We simulate the September 10, 2014 CME/ICME event and its propagation
  to Earth using the Alfven Wave Solar Model (AWSoM) within the Space
  Weather Modeling Framework. This fast CME that reached the Earth with an
  average transit time of 920 km/s and produced wide spread disturbances
  in the corona and heliosphere. We conduct detailed comparisons of this
  CME simulation with observations of a range phenomena including waves
  with SDO/AIA and coronal shocks with LASCO C2/C3 and the corresponding
  type II radio burst. We examine the ICME structure with STEREO/SECCHI
  and in situ observations from ACE and Wind, and we examine the impact
  on low frequency turbulence observed at 1AU with Wind. Furthermore,
  we track the simulated CME-driven shock surfaces and derive the shock
  parameters (plasma frequency, theta BN and compression ratio), which
  we relate to the observed type II radio burst. We finally discuss the
  role of wave reflection, compression and dissipation on the turbulent
  energy changes at the shock and in the sheath and ICME ejecta.

Title: Validating the Alfven Wave Solar Atmosphere (AWSoM) Model
    from the Low Corona to 1 AU
Authors: Sachdeva, N.; van der Holst, B.; Manchester, W.; Toth, G.;
   Lloveras, D. G.; Vásquez, A. M.; Lamy, P.; Jackson, B. V.; Henney,
   C. J.
Bibcode: 2019AGUFMSH51A..04S
Altcode:
  The coronal/solar wind model, the Alfven Wave Solar atmosphere Model
  (AWSoM) a component within the Space Weather Modeling Framework (SWMF)
  follows a self-consistent physics-based global description of coronal
  heating and solar wind acceleration. AWSoM includes a description
  of low-frequency forward and counter-propagating Alfven waves that
  non-linearly interact resulting in a turbulent cascade and dissipative
  heating. In addition, there are separate temperatures for electrons and
  protons with collisional and collisionless heat conduction applied only
  to electrons and radiative losses based on the Chianti model. AWSoM
  extends from the base of the transition region where the strong
  density gradient necessitates self-consistent treatment of Alfven wave
  reflection and balanced turbulence. It includes a stochastic heating
  model as well as a description of proton parallel and perpendicular
  temperatures and kinetic instabilities based on temperature anisotropy
  and plasma beta.To validate AWSoM, we model Carrington rotations
  representative of solar minimum conditions and compare the simulation
  results with a comprehensive suite of observations. In the low corona
  (r &lt; 1.25 Rs), we compare with EUV images from both STEREOA/EUVI
  and SDO/AIA and to three-dimensional tomographic reconstructions of
  the electron temperature and density based on these same data. We
  also compare the model to tomographic reconstructions of the electron
  density from SOHO/LASCO observations (2.55 &lt; r &lt; 6 Rs). In
  the heliosphere, we compare model predictions of solar wind speed
  with velocity reconstructions from Interplanetary Scintillation
  observations. For comparison with observations near the Earth, we
  use OMNI data. Our results show that the AWSoM model performs well
  in quantitative agreement with the observations between the inner
  corona and 1 AU. In the lower corona, the model and the tomographic
  reconstructions agree within 20%-30% on average. The model also
  reproduces the fast solar wind speed in the polar regions. Near the
  Earth, our model shows good agreement with observations of solar wind
  velocity, electron temperature and density. The AWSoM model provides
  a comprehensive tool to study the solar corona and larger heliosphere
  with current and future solar missions as well as being well suited
  for space weather predictions.

Title: Identifying Solar Flare Precursors Using Time Series of
    SDO/HMI Images and SHARP Parameters
Authors: Chen, Yang; Manchester, Ward B.; Hero, Alfred O.; Toth,
   Gabor; DuFumier, Benoit; Zhou, Tian; Wang, Xiantong; Zhu, Haonan;
   Sun, Zeyu; Gombosi, Tamas I.
Bibcode: 2019SpWea..17.1404C
Altcode: 2019arXiv190400125C
  In this paper we present several methods to identify precursors that
  show great promise for early predictions of solar flare events. A data
  preprocessing pipeline is built to extract useful data from multiple
  sources, Geostationary Operational Environmental Satellites and Solar
  Dynamics Observatory (SDO)/Helioseismic and Magnetic Imager (HMI),
  to prepare inputs for machine learning algorithms. Two classification
  models are presented: classification of flares from quiet times
  for active regions and classification of strong versus weak flare
  events. We adopt deep learning algorithms to capture both spatial
  and temporal information from HMI magnetogram data. Effective feature
  extraction and feature selection with raw magnetogram data using deep
  learning and statistical algorithms enable us to train classification
  models to achieve almost as good performance as using active region
  parameters provided in HMI/Space-Weather HMI-Active Region Patch
  (SHARP) data files. Case studies show a significant increase in the
  prediction score around 20 hr before strong solar flare events.

Title: ngGONG: The Next Generation GONG - A New Solar Synoptic
    Observational Network
Authors: Hill, Frank; Hammel, Heidi; Martinez-Pillet, Valentin; de
   Wijn, A.; Gosain, S.; Burkepile, J.; Henney, C. J.; McAteer, J.; Bain,
   H. M.; Manchester, W.; Lin, H.; Roth, M.; Ichimoto, K.; Suematsu, Y.
Bibcode: 2019BAAS...51g..74H
Altcode: 2019astro2020U..74H
  The white paper describes a next-generation GONG, a ground-based
  geographically distributed network of instrumentation to continually
  observe the Sun. This would provide data for solar magnetic field
  research and space weather forecasting, and would extend the time
  coverage of helioseismology.

Title: Tomography of the Solar Corona with the Wide-Field Imager
    for the Parker Solar Probe
Authors: Vásquez, Alberto M.; Frazin, Richard A.; Vourlidas, Angelos;
   Manchester, Ward B.; van der Holst, Bart; Howard, Russell A.; Lamy,
   Philippe
Bibcode: 2019SoPh..294...81V
Altcode:
  The Wide-field Imager for the Parker Solar Probe (PSP/WISPR) comprises
  two telescopes that record white-light total brightness [B ] images of
  the solar corona. Their fields of view cover a widely changing range
  of heliocentric heights over the 24 highly eccentric orbits planned for
  the mission. In this work, the capability of PSP/WISPR data to carry out
  tomographic reconstructions of the three-dimensional (3D) distribution
  of the coronal electron density is investigated. Based on the precise
  orbital information of the mission, B -images for Orbits 1, 12, and 24
  are synthesized from a 3D magnetohydrodynamic model of the corona. For
  each orbit, the time series of synthetic images is used to carry out a
  tomographic reconstruction of the coronal electron density and results
  are compared with the model. As the PSP perihelion decreases, the range
  of heights that can be tomographically reconstructed progressively
  shifts to lower values, and the period required to gather the data
  decreases. For Orbit 1 tomographic reconstruction is not possible. For
  Orbit 12, tomographic reconstruction is possible in the heliocentric
  height range ≈5 -15 R<SUB>⊙</SUB>, over a region spanning up to
  ≈160<SUP>∘</SUP> in Carrington longitude, with data gathered over
  a ≈3.4 day-long period. For Orbit 24, tomographic reconstruction is
  possible in the heliocentric height range ≈3 -10 R<SUB>⊙</SUB>, over
  a region spanning up to ≈170<SUP>∘</SUP> in Carrington longitude,
  with data gathered over a ≈2.8 day-long period.

Title: SPECTRUM: Synthetic Spectral Calculations for Global Space
    Plasma Modeling
Authors: Szente, J.; Landi, E.; Manchester, W. B., IV; Toth, G.;
   van der Holst, B.; Gombosi, T. I.
Bibcode: 2019ApJS..242....1S
Altcode:
  High-resolution spectroscopy is the most accurate tool for measuring
  the properties of the solar corona. However, interpreting measured
  line intensities and line profiles emitted by the optically thin solar
  corona is complicated by line-of-sight (LOS) integration, which leads to
  measuring weighted averages of the plasma properties along the LOS. LOS
  integration effects can be removed by combining CHIANTI spectral
  emissivities with a 3D global model of the solar corona to calculate
  the contribution of all structures along the LOS to the measured
  intensities. In this paper, we describe SPECTRUM, a postprocessing tool
  that can calculate the emission from the optically thin solar corona
  by combining 3D magnetohydrodynamic (MHD) space plasma simulation
  results with the CHIANTI database. Doppler-shifted, nonthermal line
  broadening due to low-frequency Alfvén waves and anisotropic proton
  and isotropic electron temperatures can be individually taken into
  account during calculations. Synthetic spectral calculations can then
  be used for model validation, for interpretation of solar observations,
  and for forward modeling purposes. SPECTRUM is implemented within the
  Space Weather Modeling Framework (SWMF) and is therefore publicly
  available. In this paper, we describe the SPECTRUM module and show
  its applications by comparing synthetic spectra using simulation data
  by the 3D MHD Alfvén Wave Solar Model with observations done by the
  Hinode/Extreme-ultraviolet Imaging Spectrometer during Carrington
  rotations 2063 and 2082.

Title: Synoptic Studies of the Sun as a Key to Understanding Stellar
    Astrospheres
Authors: Martinez Pillet, Valentin; Hill, Frank; Hammel, Heidi B.;
   de Wijn, Alfred G.; Gosain, Sanjay; Burkepile, Joan; Henney, Carl;
   McAteer, R. T. James; Bain, Hazel; Manchester, Ward; Lin, Haosheng;
   Roth, Markus; Ichimoto, Kiyoshi; Suematsu, Yoshinori
Bibcode: 2019BAAS...51c.110M
Altcode: 2019astro2020T.110M; 2019arXiv190306944M
  Ground-based solar observations provide key contextual data (i.e., the
  "big picture") to produce a complete description of the only astrosphere
  we can study in situ: our Sun's heliosphere. This white paper outlines
  the current paradigm for ground-based solar synoptic observations,
  and indicates those areas that will benefit from focused attention.

Title: Magnetohydrodynamic Simulations for the First and Second
    Parker Solar Probe Encounter
Authors: van der Holst, Bart; Chandran, B. D. G.; Borovikov, D.;
   Klein, K. G.; Manchester, W. B., IV; Kasper, J. C.
Bibcode: 2019shin.confE..49V
Altcode:
  We examine Alfvén Wave Solar atmosphere Model (AWSoM) simulations
  of the first and second Parker Solar Probe (PSP) encounter. AWSoM
  allows us to interpret the PSP data in the context of coronal heating
  via Alfvén wave turbulence. The coronal heating and acceleration is
  addressed via outward-propagating low-frequency Alfvén waves that
  are partially reflected by Alfvén speed gradients. The nonlinear
  interaction of these counter-propagating waves results in a turbulent
  energy cascade. To apportion the wave dissipation to the electron and
  anisotropic proton temperatures, we employ an improved version of the
  theories of linear wave damping and nonlinear stochastic heating as
  described by Chandran et al. 2011. Attention is given to the plasma
  mass density, velocity, and magnetic fields, temperature anisotropy,
  and wave turbulence. We will also describe the large-scale structures
  that PSP might have passed through, for instance whether PSP was in the
  fast or slow wind and when PSP crossed the heliospheric current sheet.

Title: Applying Machine Learning and Numerical Simulations to
    Understanding the Physical Processes of Solar Flare Onset
Authors: Manchester, Ward; Sun, Hu; Chen, Yang; Liu, Yang; Jin, Meng
Bibcode: 2019shin.confE.200M
Altcode:
  We apply deep learning algorithms to train binary strong/weak
  classification models using active region parameters provided in
  HMI/Space-Weather HMI-Active Region Patch (SHARP) data files. We
  identify several active regions which show a sudden transition of
  the prediction score indicating near certainty of an M/X class flare
  several hours before the event. We examine the HMI vector magnetogram
  data for these events to determine if there are common features in
  the photospheric magnetic field related to the energy build up and a
  possible eruption threshold. We also compare observed magnetic field
  to simulations of magnetic flux emergence to identify the physical
  processes driving the magnetic evolution toward eruptive behavior.

Title: Nonequilibrium ionization effects on coronal plasma diagnostics
    and elemental abundance measurements
Authors: Shi, Tong; Landi, Enrico; Manchester, Ward
Bibcode: 2019shin.confE..71S
Altcode:
  Plasma diagnostics and elemental abundance measurements are crucial to
  help us understand the formation and dynamics of the solar wind. It
  is commonly assumed that the solar wind is in equilibrium ionization
  (EI). Here we use a theoretical solar wind model to study whether the
  non-equilibrium ionization (NEI) has any effect on the fast solar
  wind. We find that the measured plasma density and temperature are
  only slightly affected, but NEI systematically shifts the differential
  emission measure (DEM) towards lower temperature on all heights. In
  addition, NEI significantly affects the first ionization potential
  (FIP) bias and abundance measurements. The EI assumption can lead
  up to a factor of 4 error at 1.5 solar radii for Mg/Ne, Fe/S, and
  Ar/Fe line pairs. Therefore, it is very important to consider the NEI
  effect when doing the DEM diagnostics and measuring the FIP bias and
  elemental abundance.

Title: Validating the Alfven Wave Solar Model (AWSoM) from the lower
    corona to 1 AU
Authors: Sachdeva, Nishtha; Manchester, Ward; van der Holst, Bart;
   Toth, Gabor; Vasquez, Alberto; Jackson, Bernard; Lloveras, Diego G.;
   Mac Cormack, Cecilia; Yu, Hsiu-Shan
Bibcode: 2019EGUGA..21.1465S
Altcode:
  We examine the steady state three-dimensional MHD simulations of the
  solar corona carried out with the new version of the Alfven Wave Solar
  Model (AWSoM) within the Space Weather Modeling framework (SWMF). AWSoM
  addresses the acceleration and heating of the solar corona via the
  interaction between counter-propagating Alfven waves. This non-linear
  interaction between the outward propagating low-frequency Alfven waves
  and those partially reflected by the speed gradients results in a
  turbulent energy cascade. The model uses physics-based partitioning
  of wave-dissipated heat between isotropic electron and anisotropic
  proton temperatures. To validate the AWSoM model, we select rotations
  representative of the solar minimum and maximum conditions and compare
  our simulation results with a comprehensive suite of observations. We
  use three-dimensional tomographic reconstructions of the electron
  temperature and density in the inner corona (r &lt; 1.25 Rsun) based
  on multi-wavelength extreme ultraviolet images from STEREO/EUVI
  and SDO/AIA. For comparison with observations made near the Earth,
  we compare the model with OMNI data. At different radial distances
  between 20 Rsun and 1 AU, we compare the model with reconstructions
  made with Interplanetary Scintillation (IPS) observations. Observations
  are compared with the simulated model results of plasma mass density,
  velocity, and magnetic fields, temperature anisotropy, and wave
  turbulence. Our results at solar minimum show that the improved AWSoM
  model performs well in agreement with the observations between inner
  corona and 1 AU. In the lower corona the model and the tomographic
  reconstructions match within a 20 % accuracy. Near the Earth, our model
  shows good agreement with observations of solar wind velocity, electron
  temperature and magnetic field. However, the electron density at 1 AU
  is overpredicted by the model for the solar minimum simulations. While
  this model version is already an improvement over previous predictions,
  we plan to validate our model using more Carrington rotations. The AWSoM
  model presents an extensive application to study the solar corona and
  larger heliosphere in concert with current and future solar missions.

Title: Predictions for the First Parker Solar Probe Encounter
Authors: van der Holst, B.; Manchester, W. B., IV; Klein, K. G.;
   Kasper, J. C.
Bibcode: 2019ApJ...872L..18V
Altcode: 2019arXiv190203921V
  We examine Alfvén Wave Solar atmosphere Model (AWSoM) predictions
  of the first Parker Solar Probe (PSP) encounter. We focus on the 12
  day closest approach centered on the first perihelion. AWSoM allows
  us to interpret the PSP data in the context of coronal heating via
  Alfvén wave turbulence. The coronal heating and acceleration is
  addressed via outward-propagating low-frequency Alfvén waves that
  are partially reflected by Alfvén speed gradients. The nonlinear
  interaction of these counter-propagating waves results in a turbulent
  energy cascade. To apportion the wave dissipation to the electron and
  anisotropic proton temperatures, we employ the results of the theories
  of linear wave damping and nonlinear stochastic heating as described
  by Chandran et al. We find that during the first encounter, PSP was
  in close proximity to the heliospheric current sheet (HCS) and in the
  slow wind. PSP crossed the HCS two times, at 2018 November 3 UT 01:02
  and 2018 November 8 UT 19:09, with perihelion occurring on the south of
  side of the HCS. We predict the plasma state along the PSP trajectory,
  which shows a dominant proton parallel temperature causing the plasma
  to be firehose unstable.

Title: Global Magnetohydrodynamics Simulation of EUV Waves and Shocks
    from the X8.2 Eruptive Flare on 2017 September 10
Authors: Jin, Meng; Liu, Wei; Cheung, Mark; Nitta, Nariaki; Manchester,
   Ward; Ofman, Leon; Downs, Cooper; Petrosian, Vahe; Omodei, Nicola
Bibcode: 2018csc..confE..66J
Altcode:
  As one of the largest flare-CME eruptions during solar cycle 24, the
  2017 September 10 X8.2 flare event is associated with spectacular
  global EUV waves that transverse almost the entire visible solar
  disk, a CME with speed &gt; 3000 km/s, which is one of the fastest
  CMEs ever recorded, and &gt;100 MeV Gamma-ray emission lasting for
  more than 12 hours. All these unique observational features pose new
  challenge on current numerical models to reproduce the multi-wavelength
  observations. To take this challenge, we simulate the September 10 event
  using a global MHD model (AWSoM: Alfven Wave Solar Model) within the
  Space Weather Modeling Framework and initiate CMEs by Gibson-Low flux
  rope. We conduct detailed comparisons of the synthesized EUV images with
  SDO/AIA observations of global EUV waves. We find that the simulated
  EUV wave morphology and kinematics are sensitive to the orientation
  of the initial flux rope introduced to the source active region. An
  orientation with the flux-rope axis in the north-south direction
  produces the best match to the observations, which suggests that EUV
  waves may potentially be used to constrain the flux-rope geometry for
  such limb or behind-the-limb eruptions that lack good magnetic field
  observations. We also compare observed and simulated EUV intensities
  in multiple AIA channels to perform thermal seismology of the global
  corona. Furthermore, we track the 3D CME-driven shock surface in the
  simulation and derive the time-varying shock parameters together with
  the dynamic magnetic connectivity between the shock and the surface
  of the Sun, with which we discuss the role of CME-driven shocks in
  the long-duration Gamma-ray events.

Title: Multispecies and Multifluid MHD Approaches for the Study of
    Ionospheric Escape at Mars
Authors: Regoli, L. H.; Dong, C.; Ma, Y.; Dubinin, E.; Manchester,
   W. B.; Bougher, S. W.; Welling, D. T.
Bibcode: 2018JGRA..123.7370R
Altcode:
  A detailed model-model comparison between the results provided by
  a multispecies and a multifluid magnetohydrodynamic (MHD) code for
  the escape of heavy ions in the Martian-induced magnetosphere is
  presented. The results from the simulations are analyzed and compared
  against a statistical analysis of the outflow of heavy ions obtained
  by the Mars Atmosphere and Volatile EvolutioN/Suprathermal and Thermal
  Ion Composition instrument over an extended period of time in order
  to estimate the influence of magnetic forces in the ion escape. Both
  MHD models are run with the same chemical reactions and ion species
  in a steady state mode under idealized solar conditions. Apart from
  being able to reproduce the asymmetries observed in the ion escape,
  it is found that the multifluid approach provides results that are
  closer to those inferred from the ion data. It is also found that the
  j × B force term is less effective in accelerating the ions in the
  models when compared with the Mars Atmosphere and Volatile EvolutioN
  results. Finally, by looking at the contribution of the plume and
  the ion escape rates at different distances along the tail with the
  multifluid model, it is also found that the escape of heavy ions has
  important variabilities along the tail, meaning that the apoapsis
  of a spacecraft studying atmospheric escape can affect the estimates
  obtained.

Title: Global Magnetohydrodynamics Simulation of EUV Waves and Shocks
    from the X8.2 Eruptive Flare on 2017 September 10
Authors: Jin, Meng; Liu, Wei; Cheung, Mark; Nitta, Nariaki; Manchester,
   Ward; Ofman, Leon; Downs, Cooper; Petrosian, Vahe; Omodei, Nicola
Bibcode: 2018shin.confE.207J
Altcode:
  As one of the largest flare-CME eruptions during solar cycle 24, the
  2017 September 10 X8.2 flare event is associated with spectacular
  global EUV waves that transverse almost the entire visible solar
  disk, a CME with speed &gt; 3000 km/s, which is one of the fastest
  CMEs ever recorded, and &gt;100 MeV Gamma-ray emission lasting for
  more than 12 hours. All these unique observational features pose new
  challenge on current numerical models to reproduce the multi-wavelength
  observations. To take this challenge, we simulate the September 10 event
  using a global MHD model (AWSoM: Alfven Wave Solar Model) within the
  Space Weather Modeling Framework and initiate CMEs by Gibson-Low flux
  rope. We conduct detailed comparisons of the synthesized EUV images with
  SDO/AIA observations of global EUV waves. We find that the simulated
  EUV wave morphology and kinematics are sensitive to the orientation
  of the initial flux rope introduced to the source active region. An
  orientation with the flux-rope axis in the north-south direction
  produces the best match to the observations, which suggests that EUV
  waves may potentially be used to constrain the flux-rope geometry for
  such limb or behind-the-limb eruptions that lack good magnetic field
  observations. We also compare observed and simulated EUV intensities
  in multiple AIA channels to perform thermal seismology of the global
  corona. Furthermore, we track the 3D CME-driven shock surface in the
  simulation and derive the time-varying shock parameters together with
  the dynamic magnetic connectivity between the shock and the surface
  of the Sun, with which we discuss the role of CME-driven shocks in
  the long-duration Gamma-ray events.

Title: Coronal magnetic field extrapolation with AWSoM MHD relaxation
Authors: Shi, Tong; Manchester, Ward
Bibcode: 2018shin.confE..87S
Altcode:
  Coronal mass ejections are known to be the major source of disturbances
  in the solar wind capable of affecting geomagnetic environments. In
  order for accurate predictions of such space weather events, a
  data-driven simulation is needed. The first step towards such a
  simulation is to extrapolate the magnetic field from the observed
  field that is only at the solar surface. In this poster, we present
  results of a new code of magnetic field extrapolation with direct
  magnetohydrodynamics (MHD) relaxation using the Alfven Wave Solar Model
  (AWSoM) in the Space Weather Modeling Framework. The obtained field is
  self-consistent with our model and can be used later in time-dependent
  simulations without modifications of the equations. We use the Low
  and Lou analytical solution to test our results and they reach a good
  agreement. We show robustness of our code that the MHD solution can
  be stabilized even with noise applied to the magnetic field at the
  bottom boundary. This new extrapolation method is then applied to the
  magnetic field from the observed data, demonstrating the capabilities
  of this code.

Title: Extended MHD modeling of the steady solar corona and the
    solar wind
Authors: Gombosi, Tamas I.; van der Holst, Bart; Manchester, Ward B.;
   Sokolov, Igor V.
Bibcode: 2018LRSP...15....4G
Altcode: 2018arXiv180700417G
  The history and present state of large-scale magnetohydrodynamic
  modeling of the solar corona and the solar wind with steady or
  quasi-steady coronal physics is reviewed. We put the evolution of
  ideas leading to the recognition of the existence of an expanding solar
  atmosphere into historical context. The development and main features
  of the first generation of global corona and solar wind models are
  described in detail. This historical perspective is also applied to
  the present suite of global corona and solar wind models. We discuss
  the evolution of new ideas and their implementation into numerical
  simulation codes. We point out the scientific and computational
  challenges facing these models and discuss the ways various groups tried
  to overcome these challenges. Next, we discuss the latest, state-of-the
  art models and point to the expected next steps in modeling the corona
  and the interplanetary medium.

Title: Tracking Solar Type II Bursts with the Sun Radio Interferometer
    Space Experiment (SunRISE)
Authors: Hegedus, Alexander; Kasper, Justin; Manchester, Ward;
   Lazio, Joseph
Bibcode: 2018shin.confE.227H
Altcode:
  The Earth's Ionosphere limits radio measurements on its surface,
  blocking out any radiation below 10 MHz. Valuable insight into many
  astrophysical processes could be gained by having a radio interferometer
  in space to image the low frequency window, which has never been
  achieved. One application for such a system is observing type II
  bursts tracking solar energetic particle acceleration Coronal Mass
  Ejection (CME)-driven shocks. In this work we create a simulated data
  processing pipeline for the pathfinder mission SunRISE, a 6 CubeSat
  interferometer to circle the Earth in a GEO graveyard orbit, and
  evaluate its performance in the task of localizing these type II bursts.

Title: Tracking Solar Type II Bursts with Space Based Radio
    Interferometers
Authors: Hegedus, Alexander M.; Kasper, Justin C.; Manchester, Ward B.
Bibcode: 2018AAS...23240501H
Altcode:
  The Earth’s Ionosphere limits radio measurements on its surface,
  blocking out any radiation below 10 MHz. Valuable insight into many
  astrophysical processes could be gained by having a radio interferometer
  in space to image the low frequency window for the first time. One
  application is observing type II bursts tracking solar energetic
  particle acceleration in Coronal Mass Ejections (CMEs). In this work
  we create a simulated data processing pipeline for several space based
  radio interferometer (SBRI) concepts and evaluate their performance
  in the task of localizing these type II bursts.Traditional radio
  astronomy software is hard coded to assume an Earth based array. To
  circumvent this, we manually calculate the antenna separations and
  insert them along with the simulated visibilities into a CASA MS file
  for analysis. To create the realest possible virtual input data, we take
  a 2-temperature MHD simulation of a CME event, superimpose realistic
  radio emission models from the CME-driven shock front, and propagate the
  signal through simulated SBRIs. We consider both probabilistic emission
  models derived from plasma parameters correlated with type II bursts,
  and analytical emission models using plasma emission wave interaction
  theory.One proposed SBRI is the pathfinder mission SunRISE, a 6 CubeSat
  interferometer to circle the Earth in a GEO graveyard orbit. We test
  simulated trajectories of SunRISE and image what the array recovers,
  comparing it to the virtual input. An interferometer on the lunar
  surface would be a stable alternative that avoids noise sources
  that affect orbiting arrays, namely the phase noise from positional
  uncertainty and atmospheric 10s-100s kHz noise. Using Digital Elevation
  Models from laser altimeter data, we test different sets of locations
  on the lunar surface to find near optimal configurations for tracking
  type II bursts far from the sun. Custom software is used to model
  the response of different array configurations over the lunar year,
  combining ephemerides of the sun and moon to correlate the virtual
  data. We analyze the pros and cons of all approaches and offer
  recommendations for SRBIs that track type II bursts.

Title: MHD Modeling of ICMEs and Heliosphere Disturbances with
    Application to Space Weather Forecasting
Authors: Manchester, Ward; Jin, Meng; van der Holst, Bart; Sokolov,
   Igor
Bibcode: 2018tess.conf41103M
Altcode:
  We examine CME simulation results derived from the Eruptive Event
  Generator Gibson-Low EEGGL, which was recently installed at the
  Community Coordinated Modeling Center (CCMC). The EEGGL tool allows us
  to simulate observed CME events by automatically determining parameters
  for the analytical Gibson &amp; Low (GL) flux rope model with data
  from synoptic magnetograms and CME coronagraph observations. The CME
  simulations are carried out with the Alfven Wave Solar Model (AWSoM),
  which allow us to simulate the propagation of ICMEs from the low corona
  through the solar wind to 1 AU. We compare model predictions of the
  spatial structure and time-evolution of heliospheric disturbances to
  in situ observations at 1AU. Attention is given to the ability of the
  simulations to reproduce the observed plasma mass density, velocity,
  and magnetic fields. We probe the validity and capability of the
  numerical models and question their potential to forecast solar wind
  conditions and ICME disturbances, while looking forward to the future
  capabilities of Solar Probe Plus and Solar Orbiter.

Title: Tracking Solar Type II Bursts to .5 AU with Radio
    Interferometers on the Lunar Surface
Authors: Hegedus, Alexander Michael; Kasper, Justin Christophe;
   Manchester, Ward
Bibcode: 2018tess.conf22003H
Altcode:
  The Earth's Ionosphere limits radio measurements on its surface,
  blocking out any radiation below 10 MHz. Valuable insight into various
  astrophysical processes could be gained by having a radio interferometer
  in space to image this frequency window for the first time. One proposed
  incarnation of this is the pathfinder mission SunRISE, an interferometer
  to orbit around the Earth in the form of multiple smallsats working
  to observe Type II bursts tracking solar energetic particle (SEP)
  acceleration in Coronal Mass Ejections (CMEs). An interferometer on
  the lunar surface would be a stable alternative that avoids both the
  positional uncertainty and 10s-100s kHz noise that would affect orbiting
  arrays. Arrays could also be larger, having better resolution at lower
  frequencies, allowing us to image Type II bursts and track gradual SEP
  events out to .5 AU, far further out than a smaller orbiting array. <P
  />Using Digital Elevation Models partially from Lunar Reconnaissance
  Orbiter's Lunar Orbiter Laser Altimeter (LOLA) instrument, we test
  different sets of locations on the lunar surface to find near optimal
  configurations for planar arrays for tracking Solar Radio Bursts far
  from the sun. Custom software is used to model the response of different
  array configurations over the lunar year, combining ephemerides of the
  sun and moon with LOLA data to correctly correlate the virtual data. To
  create the realest possible virtual input data, we take a 2 fluid MHD
  simulation of a CME event, and superimpose realistic radio emission
  models on top of it, and propagate the signal through various simulated
  lunar interferometers. We consider both probabilistic emission models
  derived from data cuts of various Type II burst correlated variables,
  and analytical emission models using plasma emission wave interaction
  theory. We conclude by offering recommendations for the location and
  geometry of a future lunar radio interferometer.

Title: Global Magnetohydrodynamics Simulation of EUV Waves and Shocks
    from the X8.2 Eruptive Flare on 2017 September 10
Authors: Jin, Meng; Liu, Wei; Cheung, Chun Ming Mark; Nitta, Nariaki;
   Manchester, Ward; Ofman, Leon; Downs, Cooper; Petrosian, Vahe;
   Omodei, Nicola
Bibcode: 2018tess.conf31905J
Altcode:
  As one of the largest flare-CME eruptions during solar cycle 24, the
  2017 September 10 X8.2 flare event is associated with spectacular
  global EUV waves that transverse almost the entire visible solar
  disk, a CME with speed &gt; 3000 km/s, which is one of the fastest
  CMEs ever recorded, and &gt;100 MeV Gamma-ray emission lasting for
  more than 12 hours. All these unique observational features pose new
  challenge on current numerical models to reproduce the multi-wavelength
  observations. To take this challenge, we simulate the September 10 event
  using a global MHD model (AWSoM: Alfven Wave Solar Model) within the
  Space Weather Modeling Framework and initiate CMEs by Gibson-Low flux
  rope. We conduct detailed comparisons of the synthesized EUV images with
  SDO/AIA observations of global EUV waves. We find that the simulated
  EUV wave morphology and kinematics are sensitive to the orientation
  of the initial flux rope introduced to the source active region. An
  orientation with the flux-rope axis in the north-south direction
  produces the best match to the observations, which suggests that EUV
  waves may potentially be used to constrain the flux-rope geometry for
  such limb or behind-the-limb eruptions that lack good magnetic field
  observations. We also compare observed and simulated EUV intensities
  in multiple AIA channels to perform thermal seismology of the global
  corona. Furthermore, we track the 3D CME-driven shock surface in the
  simulation and derive the time-varying shock parameters together with
  the dynamic magnetic connectivity between the shock and the surface
  of the Sun, with which we discuss the role of CME-driven shocks in
  the long-duration Gamma-ray events.

Title: The Origin, Early Evolution and Predictability of Solar
    Eruptions
Authors: Green, Lucie M.; Török, Tibor; Vršnak, Bojan; Manchester,
   Ward; Veronig, Astrid
Bibcode: 2018SSRv..214...46G
Altcode: 2018arXiv180104608G
  Coronal mass ejections (CMEs) were discovered in the early 1970s
  when space-borne coronagraphs revealed that eruptions of plasma
  are ejected from the Sun. Today, it is known that the Sun produces
  eruptive flares, filament eruptions, coronal mass ejections and failed
  eruptions; all thought to be due to a release of energy stored in
  the coronal magnetic field during its drastic reconfiguration. This
  review discusses the observations and physical mechanisms behind this
  eruptive activity, with a view to making an assessment of the current
  capability of forecasting these events for space weather risk and impact
  mitigation. Whilst a wealth of observations exist, and detailed models
  have been developed, there still exists a need to draw these approaches
  together. In particular more realistic models are encouraged in order
  to asses the full range of complexity of the solar atmosphere and the
  criteria for which an eruption is formed. From the observational side,
  a more detailed understanding of the role of photospheric flows and
  reconnection is needed in order to identify the evolutionary path that
  ultimately means a magnetic structure will erupt.

Title: Magnetic field extrapolation with MHD relaxation using AWSoM
Authors: Shi, T.; Manchester, W.; Landi, E.
Bibcode: 2017AGUFMSH13A2458S
Altcode:
  Coronal mass ejections are known to be the major source of disturbances
  in the solar wind capable of affecting geomagnetic environments. In
  order for accurate predictions of such space weather events,
  a data-driven simulation is needed. The first step towards such a
  simulation is to extrapolate the magnetic field from the observed field
  that is only at the solar surface. Here we present results of a new
  code of magnetic field extrapolation with direct magnetohydrodynamics
  (MHD) relaxation using the Alfvén Wave Solar Model (AWSoM) in the Space
  Weather Modeling Framework. The obtained field is self-consistent with
  our model and can be used later in time-dependent simulations without
  modifications of the equations. We use the Low and Lou analytical
  solution to test our results and they reach a good agreement. We also
  extrapolate the magnetic field from the observed data. We then specify
  the active region corona field with this extrapolation result in the
  AWSoM model and self-consistently calculate the temperature of the
  active region loops with Alfvén wave dissipation. Multi-wavelength
  images are also synthesized.

Title: A Spectroscopic Study of the Energy Deposition in the Low
Corona: Connecting Global Modeling to Observations
Authors: Szente, J.; Landi, E.; Toth, G.; Manchester, W.; van der
   Holst, B.; Gombosi, T. I.
Bibcode: 2017AGUFMSH41C..06S
Altcode:
  We are looking for signatures of coronal heating process using a
  physically consistent 3D MHD model of the global corona. Our approach is
  based on the Alfvén Wave Solar atmosphere Model (AWSoM), with a domain
  ranging from the upper chromosphere (50,000K) to the outer corona,
  and the solar wind is self-consistently heated and accelerated by the
  dissipation of low-frequency Alfvén waves. Taking into account separate
  electron and anisotropic proton heating, we model the coronal plasma
  at the same time and location as observed by Hinode/EIS, and calculate
  the synthetic spectra that we compare with the observations. With
  the obtained synthetic spectra, we are able to directly calculate
  line intensities, line width, thermal and nonthermal motions, line
  centroids, Doppler shift distributions and compare our predictions
  to real measurements. Our results directly test the extent to which
  Alfvénic heating is present in the low corona.

Title: Tomographic Validation of the AWSoM Model of the Inner Corona
    During Solar Minima
Authors: Manchester, W.; Vásquez, A. M.; Lloveras, D. G.; Mac Cormack,
   C.; Nuevo, F.; Lopez-Fuentes, M.; Frazin, R. A.; van der Holst, B.;
   Landi, E.; Gombosi, T. I.
Bibcode: 2017AGUFMSH51C2512M
Altcode:
  Continuous improvement of MHD three-dimensional (3D) models of the
  global solar corona, such as the Alfven Wave Solar Model (AWSoM) of
  the Space Weather Modeling Framework (SWMF), requires testing their
  ability to reproduce observational constraints at a global scale. To
  that end, solar rotational tomography based on EUV image time-series
  can be used to reconstruct the 3D distribution of the electron density
  and temperature in the inner solar corona (r &lt; 1.25 Rsun). The
  tomographic results, combined with a global coronal magnetic model, can
  further provide constraints on the energy input flux required at the
  coronal base to maintain stable structures. In this work, tomographic
  reconstructions are used to validate steady-state 3D MHD simulations
  of the inner corona using the latest version of the AWSoM model. We
  perform the study for selected rotations representative of solar
  minimum conditions, when the global structure of the corona is more
  axisymmetric. We analyse in particular the ability of the MHD simulation
  to match the tomographic results across the boundary region between the
  equatorial streamer belt and the surrounding coronal holes. The region
  is of particular interest as the plasma flow from that zone is thought
  to be related to the origin of the slow component of the solar wind.

Title: Solar Atmosphere to Earth's Surface: Long Lead Time dB/dt
    Predictions with the Space Weather Modeling Framework
Authors: Welling, D. T.; Manchester, W.; Savani, N.; Sokolov, I.;
   van der Holst, B.; Jin, M.; Toth, G.; Liemohn, M. W.; Gombosi, T. I.
Bibcode: 2017AGUFMSH34B..05W
Altcode:
  The future of space weather prediction depends on the community's
  ability to predict L1 values from observations of the solar
  atmosphere, which can yield hours of lead time. While both
  empirical and physics-based L1 forecast methods exist, it is not
  yet known if this nascent capability can translate to skilled
  dB/dt forecasts at the Earth's surface. This paper shows results
  for the first forecast-quality, solar-atmosphere-to-Earth's-surface
  dB/dt predictions. Two methods are used to predict solar wind and
  IMF conditions at L1 for several real-world coronal mass ejection
  events. The first method is an empirical and observationally based
  system to estimate the plasma characteristics. The magnetic field
  predictions are based on the Bz4Cast system which assumes that the
  CME has a cylindrical flux rope geometry locally around Earth's
  trajectory. The remaining plasma parameters of density, temperature
  and velocity are estimated from white-light coronagraphs via a variety
  of triangulation methods and forward based modelling. The second is
  a first-principles-based approach that combines the Eruptive Event
  Generator using Gibson-Low configuration (EEGGL) model with the Alfven
  Wave Solar Model (AWSoM). EEGGL specifies parameters for the Gibson-Low
  flux rope such that it erupts, driving a CME in the coronal model
  that reproduces coronagraph observations and propagates to 1AU. The
  resulting solar wind predictions are used to drive the operational
  Space Weather Modeling Framework (SWMF) for geospace. Following the
  configuration used by NOAA's Space Weather Prediction Center, this
  setup couples the BATS-R-US global magnetohydromagnetic model to the
  Rice Convection Model (RCM) ring current model and a height-integrated
  ionosphere electrodynamics model. The long lead time predictions
  of dB/dt are compared to model results that are driven by L1 solar
  wind observations. Both are compared to real-world observations from
  surface magnetometers at a variety of geomagnetic latitudes. Metrics
  are calculated to examine how the simulated solar wind drivers
  impact forecast skill. These results illustrate the current state
  of long-lead-time forecasting and the promise of this technology for
  operational use.

Title: The Interaction of Coronal Mass Ejections with Alfvenic
    Turbulence
Authors: Manchester, W.; van der Holst, B.
Bibcode: 2017AGUFMSH42B..06M
Altcode:
  We provide a first attempt to understand the interaction between Alfven
  wave turbulence, kinetic instabilities and temperature anisotropies
  in the environment of a fast coronal mass ejection (CME). The impact
  of a fast CME on the solar corona causes turbulent energy, thermal
  energy and dissipative heating to increase by orders of magnitude, and
  produces conditions suitable for a host of kinetic instabilities. We
  study these CME-induced effects with the recently developed Alfven Wave
  Solar Model, with which we are able to self-consistently simulate the
  turbulent energy transport and dissipation as well as isotropic electron
  heating and anisotropic proton heating. Furthermore, the model also
  offers the capability to address the effects of firehose, mirror mode,
  and cyclotron kinetic instabilities on proton energy partitioning,
  all in a global-scale numerical simulation. We find turbulent energy
  greatly enhanced in the CME sheath, strong wave reflection at the
  shock, which leads to wave dissipation rates increasing by more than
  a factor of 100. In contrast, wave energy is greatly diminished
  by adiabatic expansion in the flux rope. Finally, we find proton
  temperature anisotropies are limited by kinetic instabilities to a
  level consistent with solar wind observations.

Title: The Sun Radio Imaging Space Experiment (SunRISE) Mission
Authors: Kasper, J. C.; Lazio, J.; Alibay, F.; Amiri, N.; Bastian,
   T.; Cohen, C.; Landi, E.; Hegedus, A. M.; Maksimovic, M.; Manchester,
   W.; Reinard, A.; Schwadron, N.; Cecconi, B.; Hallinan, G.; Krupar, V.
Bibcode: 2017AGUFMSH41B2760K
Altcode:
  Radio emission from coronal mass ejections (CMEs) is a direct tracer
  of particle acceleration in the inner heliosphere and potential
  magnetic connections from the lower solar corona to the larger
  heliosphere. Energized electrons excite Langmuir waves, which then
  convert into intense radio emission at the local plasma frequency,
  with the most intense acceleration thought to occur within 20 R_S. The
  radio emission from CMEs is quite strong such that only a relatively
  small number of antennas is required to detect and map it, but many
  aspects of this particle acceleration and transport remain poorly
  constrained. Ground-based arrays would be quite capable of tracking
  the radio emission associated with CMEs, but absorption by the Earth's
  ionosphere limits the frequency coverage of ground-based arrays (nu &gt;
  15 MHz), which in turn limits the range of solar distances over which
  they can track the radio emission (&lt; 3 R_S). The state-of-the-art
  for tracking such emission from space is defined by single antennas
  (Wind/WAVES, Stereo/SWAVES), in which the tracking is accomplished by
  assuming a frequency-to-density mapping; there has been some success
  in triangulating the emission between the spacecraft, but considerable
  uncertainties remain. We describe the Sun Radio Imaging Space Experiment
  (SunRISE) mission concept: A constellation of small spacecraft in a
  geostationary graveyard orbit designed to localize and track radio
  emissions in the inner heliosphere. Each spacecraft would carry a
  receiving system for observations below 25 MHz, and SunRISE would
  produce the first images of CMEs more than a few solar radii from
  the Sun. Part of this research was carried out at the Jet Propulsion
  Laboratory, California Institute of Technology, under a contract with
  the National Aeronautics and Space Administration.

Title: Two-way Effects of an ICME Event at Mars
Authors: Regoli, L.; Fang, X.; Dong, C.; Tenishev, V.; Lee, Y.;
   Bougher, S. W.; Manchester, W.
Bibcode: 2017AGUFMSM33B2644R
Altcode:
  The influence of enhanced solar activity on planetary magnetospheres
  is a subject of great interest. At Mars, given the small size
  of its induced magnetosphere compared to the size of the planet,
  a gravitationally bound oxygen corona extends above the bow shock
  upstream of the planet. These oxygen atoms can be ionized by different
  processes and precipitate into the upper atmosphere of Mars. When they
  deposit their energy, they heat the thermosphere locally according to
  the path they follow which is mainly determined by the magnetic field
  configuration within the induced magnetosphere. While previous studies
  have investigated the energy deposition during interplanetary coronal
  mass ejection (ICME) events, this study focuses on the effect that an
  enhanced thermosphere/ionosphere has in the surrounding environment,
  including the increased escape. For this, we use a combination of
  models comprising a global circulation model of the Martian atmosphere
  (MGITM), a 3D model of the hot oxygen corona (AMPS), a multi-fluid
  magnetohydrodynamics (MHD) model of the induced magnetosphere and a
  test particle code (MCPIT) to propagate the precipitating ions into
  the exobase.

Title: The Physical Processes of CME/ICME Evolution
Authors: Manchester, Ward; Kilpua, Emilia K. J.; Liu, Ying D.; Lugaz,
   Noé; Riley, Pete; Török, Tibor; Vršnak, Bojan
Bibcode: 2017SSRv..212.1159M
Altcode: 2017SSRv..tmp...90M
  As observed in Thomson-scattered white light, coronal mass ejections
  (CMEs) are manifest as large-scale expulsions of plasma magnetically
  driven from the corona in the most energetic eruptions from the
  Sun. It remains a tantalizing mystery as to how these erupting magnetic
  fields evolve to form the complex structures we observe in the solar
  wind at Earth. Here, we strive to provide a fresh perspective on the
  post-eruption and interplanetary evolution of CMEs, focusing on the
  physical processes that define the many complex interactions of the
  ejected plasma with its surroundings as it departs the corona and
  propagates through the heliosphere. We summarize the ways CMEs and
  their interplanetary CMEs (ICMEs) are rotated, reconfigured, deformed,
  deflected, decelerated and disguised during their journey through the
  solar wind. This study then leads to consideration of how structures
  originating in coronal eruptions can be connected to their far removed
  interplanetary counterparts. Given that ICMEs are the drivers of most
  geomagnetic storms (and the sole driver of extreme storms), this work
  provides a guide to the processes that must be considered in making
  space weather forecasts from remote observations of the corona.

Title: Eruptive event generator based on the Gibson-Low magnetic
    configuration
Authors: Borovikov, D.; Sokolov, I. V.; Manchester, W. B.; Jin, M.;
   Gombosi, T. I.
Bibcode: 2017JGRA..122.7979B
Altcode: 2017arXiv170801635B
  Coronal mass ejections (CMEs), a kind of energetic solar eruptions,
  are an integral subject of space weather research. Numerical
  magnetohydrodynamic (MHD) modeling, which requires powerful
  computational resources, is one of the primary means of studying the
  phenomenon. With increasing accessibility of such resources, grows the
  demand for user-friendly tools that would facilitate the process of
  simulating CMEs for scientific and operational purposes. The Eruptive
  Event Generator based on Gibson-Low flux rope (EEGGL), a new publicly
  available computational model presented in this paper, is an effort to
  meet this demand. EEGGL allows one to compute the parameters of a model
  flux rope driving a CME via an intuitive graphical user interface. We
  provide a brief overview of the physical principles behind EEGGL and its
  functionality. Ways toward future improvements of the tool are outlined.

Title: Spectral Analysis of Heating Processes in the Alfvén Wave
    Driven Global Corona Model
Authors: Szente, Judit; Toth, Gabor; Landi, Enrico; Manchester, Ward;
   van der Holst, Bart; Gombosi, Tamas
Bibcode: 2017shin.confE..78S
Altcode:
  Among numerous theories explaining the existence of the hot solar
  corona and continuous solar wind, one of the most successful one is
  based on wave heating. This approach describes Alfvén waves traveling
  along the magnetic field lines carrying sufficient energy to heat the
  corona and accelerate the solar wind. The wave energy is deposited
  through turbulent dissipation, which leaves identifiable traces in the
  plasma. Spectral observations have suggested the existence of wave
  heating: via the decrease of non-thermal spectral line broadening,
  and via charge state ratios of specific minor-ions reflecting the
  heating history of the solar wind plasma. We determine the extent
  to which Alfvén-waves drive the solar corona using a combination of
  spectral modeling and observational techniques. <P />In this study,
  we reevaluate observational evidence of the coronal heating process:
  we simulate observations of the global corona and its spectral line
  emission with the Alfvén Wave Solar Model (AWSoM) and compare the
  synthetic data with observations.

Title: Simulating the Initiation and Liftoff Phases of CMEs
Authors: Shi, Tong; Manchester, Ward; Landi, Enrico
Bibcode: 2017shin.confE..15S
Altcode:
  Coronal mass ejections (CMEs) are known to be the major source of
  disturbances in the solar wind capable of affecting geomagnetic
  environments. However, we are currently lacking in key information
  during the early stage of the CMEs, including the nature of the
  triggering mechanisms, that we are unable to accurately predict CME
  onset, initial propagation, and possible impact on the planetary
  systems. Here we will present preliminary results on a data-driven
  CME simulation with the Space Weather Modeling Framework. Performing
  such a simulation involves several steps: extrapolating the coronal
  magnetic field from active region vector magnetogram observations
  with nonlinear force free field model; using this field as the initial
  condition for a steady state simulation; and then driving the eruption
  by applying converging motion at the polarity inversion line at the
  lower boundary. This data-driven simulation will help us to support
  or restrict the mechanisms that provide reliable magnetic, kinematics,
  and thermal properties of a CME in its early stage, and is a required
  first step towards an accurate space weather forecast.

Title: The Sun Radio Imaging Space Experiment (SunRISE) Mission
Authors: Lazio, Joseph; Kasper, Justin; Maksimovic, Milan; Alibay,
   Farah; Amiri, Nikta; Bastian, Tim; Cohen, Christina; Landi, Enrico;
   Manchester, Ward; Reinard, Alysha; Schwadron, Nathan; Cecconi,
   Baptiste; Hallinan, Gregg; Hegedus, Alex; Krupar, Vratislav; Zaslavsky,
   Arnaud
Bibcode: 2017EGUGA..19.5580L
Altcode:
  Radio emission from coronal mass ejections (CMEs) is a direct tracer
  of particle acceleration in the inner heliosphere and potential
  magnetic connections from the lower solar corona to the larger
  heliosphere. Energized electrons excite Langmuir waves, which then
  convert into intense radio emission at the local plasma frequency,
  with the most intense acceleration thought to occur within 20 RS. The
  radio emission from CMEs is quite strong such that only a relatively
  small number of antennas is required to detect and map it, but many
  aspects of this particle acceleration and transport remain poorly
  constrained. Ground-based arrays would be quite capable of tracking
  the radio emission associated with CMEs, but absorption by the Earth's
  ionosphere limits the frequency coverage of ground-based arrays (ν
  ≳ 15 MHz), which in turn limits the range of solar distances over
  which they can track the radio emission (≲ 3RS). The state-of-the-art
  for tracking such emission from space is defined by single antennas
  (Wind/WAVES, Stereo/SWAVES), in which the tracking is accomplished by
  assuming a frequency-to-density mapping; there has been some success
  in triangulating the emission between the spacecraft, but considerable
  uncertainties remain. We describe the Sun Radio Imaging Space Experiment
  (SunRISE) mission concept: A constellation of small spacecraft in a
  geostationary graveyard orbit designed to localize and track radio
  emissions in the inner heliosphere. Each spacecraft would carry a
  receiving system for observations below 25 MHz, and SunRISE would
  produce the first images of CMEs more than a few solar radii from
  the Sun. Part of this research was carried out at the Jet Propulsion
  Laboratory, California Institute of Technology, under a contract with
  the National Aeronautics and Space Administration.

Title: Coronal Jets Simulated with the Global Alfvén Wave Solar Model
Authors: Szente, J.; Toth, G.; Manchester, W. B., IV; van der Holst,
   B.; Landi, E.; Gombosi, T. I.; DeVore, C. R.; Antiochos, S. K.
Bibcode: 2017ApJ...834..123S
Altcode:
  This paper describes a numerical modeling study of coronal jets to
  understand their effects on the global corona and their contribution
  to the solar wind. We implement jets into a well-established
  three-dimensional, two-temperature magnetohydrodynamic (MHD) solar
  corona model employing Alfvén-wave dissipation to produce a realistic
  solar-wind background. The jets are produced by positioning a compact
  magnetic dipole under the solar surface and rotating the boundary plasma
  around the dipole's magnetic axis. The moving plasma drags the magnetic
  field lines along with it, ultimately leading to a reconnection-driven
  jet similar to that described by Pariat et al. We compare line-of-sight
  synthetic images to multiple jet observations at EUV and X-ray
  bands, and find very close matches in terms of physical structure,
  dynamics, and emission. Key contributors to this agreement are the
  greatly enhanced plasma density and temperature in our jets compared
  to previous models. These enhancements arise from the comprehensive
  thermodynamic model that we use and, also, our inclusion of a dense
  chromosphere at the base of our jet-generating regions. We further
  find that the large-scale corona is affected significantly by the
  outwardly propagating torsional Alfvén waves generated by our polar
  jet, across 40° in latitude and out to 24 R<SUB>⊙</SUB>. We estimate
  that polar jets contribute only a few percent to the steady-state
  solar-wind energy outflow.

Title: Anatomy of Depleted Interplanetary Coronal Mass Ejections
Authors: Kocher, M.; Lepri, S. T.; Landi, E.; Zhao, L.; Manchester,
   W. B., IV
Bibcode: 2017ApJ...834..147K
Altcode:
  We report a subset of interplanetary coronal mass ejections (ICMEs)
  containing distinct periods of anomalous heavy-ion charge state
  composition and peculiar ion thermal properties measured by ACE/SWICS
  from 1998 to 2011. We label them “depleted ICMEs,” identified
  by the presence of intervals where C<SUP>6+</SUP>/C<SUP>5+</SUP>
  and O<SUP>7+</SUP>/O<SUP>6+</SUP> depart from the direct correlation
  expected after their freeze-in heights. These anomalous intervals within
  the depleted ICMEs are referred to as “Depletion Regions.” We find
  that a depleted ICME would be indistinguishable from all other ICMEs in
  the absence of the Depletion Region, which has the defining property
  of significantly low abundances of fully charged species of helium,
  carbon, oxygen, and nitrogen. Similar anomalies in the slow solar wind
  were discussed by Zhao et al. We explore two possibilities for the
  source of the Depletion Region associated with magnetic reconnection
  in the tail of a CME, using CME simulations of the evolution of two
  Earth-bound CMEs described by Manchester et al.

Title: Chromosphere to 1 AU Simulation of the 2011 March 7th Event:
    A Comprehensive Study of Coronal Mass Ejection Propagation
Authors: Jin, M.; Manchester, W. B.; van der Holst, B.; Sokolov, I.;
   Tóth, G.; Vourlidas, A.; de Koning, C. A.; Gombosi, T. I.
Bibcode: 2017ApJ...834..172J
Altcode: 2016arXiv161108897J
  We perform and analyze the results of a global magnetohydrodynamic
  simulation of the fast coronal mass ejection (CME) that occurred
  on 2011 March 7. The simulation is made using the newly developed
  Alfvén Wave Solar Model (AWSoM), which describes the background
  solar wind starting from the upper chromosphere and extends to
  24 R<SUB>⊙</SUB>. Coupling AWSoM to an inner heliosphere model
  with the Space Weather Modeling Framework extends the total domain
  beyond the orbit of Earth. Physical processes included in the model
  are multi-species thermodynamics, electron heat conduction (both
  collisional and collisionless formulations), optically thin radiative
  cooling, and Alfvén-wave turbulence that accelerates and heats the
  solar wind. The Alfvén-wave description is physically self-consistent,
  including non-Wentzel-Kramers-Brillouin reflection and physics-based
  apportioning of turbulent dissipative heating to both electrons and
  protons. Within this model, we initiate the CME by using the Gibson-Low
  analytical flux rope model and follow its evolution for days, in which
  time it propagates beyond STEREO A. A detailed comparison study is
  performed using remote as well as in situ observations. Although the
  flux rope structure is not compared directly due to lack of relevant
  ejecta observation at 1 au in this event, our results show that the
  new model can reproduce many of the observed features near the Sun
  (e.g., CME-driven extreme ultraviolet [EUV] waves, deflection of the
  flux rope from the coronal hole, “double-front” in the white light
  images) and in the heliosphere (e.g., shock propagation direction,
  shock properties at STEREO A).

Title: Data-constrained Coronal Mass Ejections in a Global
    Magnetohydrodynamics Model
Authors: Jin, M.; Manchester, W. B.; van der Holst, B.; Sokolov, I.;
   Tóth, G.; Mullinix, R. E.; Taktakishvili, A.; Chulaki, A.; Gombosi,
   T. I.
Bibcode: 2017ApJ...834..173J
Altcode: 2016arXiv160505360J
  We present a first-principles-based coronal mass ejection (CME)
  model suitable for both scientific and operational purposes by
  combining a global magnetohydrodynamics (MHD) solar wind model with
  a flux-rope-driven CME model. Realistic CME events are simulated
  self-consistently with high fidelity and forecasting capability by
  constraining initial flux rope parameters with observational data from
  GONG, SOHO/LASCO, and STEREO/COR. We automate this process so that
  minimum manual intervention is required in specifying the CME initial
  state. With the newly developed data-driven Eruptive Event Generator
  using Gibson-Low configuration, we present a method to derive Gibson-Low
  flux rope parameters through a handful of observational quantities so
  that the modeled CMEs can propagate with the desired CME speeds near
  the Sun. A test result with CMEs launched with different Carrington
  rotation magnetograms is shown. Our study shows a promising result
  for using the first-principles-based MHD global model as a forecasting
  tool, which is capable of predicting the CME direction of propagation,
  arrival time, and ICME magnetic field at 1 au (see the companion paper
  by Jin et al. 2016a).

Title: The Sun Radio Interferometer Space Experiment (SunRISE)
Authors: Alibay, F.; Lazio, J.; Kasper, J. C.; Amiri, N.; Bastian,
   T.; Cohen, C.; Landi, E.; Manchester, W.; Reinard, A.; Schwadron, N.;
   Hegedus, A. M.; Maksimovic, M.; Zaslavsky, A.; Cecconi, B.; Hallinan,
   G.; Krupar, V.
Bibcode: 2016AGUFMSH41B2540A
Altcode:
  Radio emission from coronal mass ejections (CMEs) is a direct tracer
  of the particle acceleration in the inner heliosphere and potential
  magnetic connections from the lower solar corona to the larger
  heliosphere. However, many aspects of this particle acceleration
  remain poorly constrained. The radio emission from CMEs is quite
  strong such that only a relatively small number of antennas is
  required to map it. However, the state-of-the-art for tracking
  such emission is only defined by single antennas (Wind/WAVES,
  Stereo/SWAVES) in which the tracking is accomplished by assuming
  a frequency-to-density mapping. These are limited to tracking CMEs
  to only a few solar radii before the frequencies of radio emission
  drop below the Earth's ionospheric cutoff. Triangulation between the
  STEREO/SWAVES and Wind/WAVES instruments have provided some initial
  constraints on particle acceleration sites at larger distances (lower
  frequencies), but the uncertainties remain considerable. We present
  the Sun Radio Imaging Space Experiment (SunRISE) mission concept:
  a space-based array designed to localize such radio emissions. This
  low-cost constellation is composed of small spacecraft placed in a
  geostationary graveyard orbit, each carrying an HF radio receiver. In
  this concept, each spacecraft would perform concurrent observations
  below 25 MHz, which would then be correlated on the ground to produce
  the first images of CMEs more than a few solar radii from the Sun. Part
  of this research was carried out at the Jet Propulsion Laboratory,
  California Institute of Technology, under a contract with the National
  Aeronautics and Space Administration.

Title: Studying the thermodynamics of coronal jets through modeling-
    and observational diagnostics techniques
Authors: Szente, J.; Manchester, W.; Landi, E.; Toth, G.; van der
   Holst, B.; Gombosi, T. I.; DeVore, C. R.; Antiochos, S. K.
Bibcode: 2016AGUFMSH21E2577S
Altcode:
  We present a comprehensive study of simulated and observed coronal jets
  using EUV and soft X-ray narrow-band images and EUV high resolution
  spectra. The goal of our study is to understand the thermodynamics
  and time evolution of jets and their impact on the coronal plasma. We
  simulate jets with a full 3D MHD coronal model with separate electron
  and proton temperatures and heating due to Alfvén wave turbulence. Due
  to the fast dynamics of the small-scale eruptive reconnections at the
  footpoint of the jet, it is essential to undertake this effort with a
  model with separate electron and proton temperatures to interpret the
  observed signatures in EUV and soft X-ray bands. The obtained synthetic
  images are compared to observations done by the instrumentations of
  SDO, STEREO and Hinode space crafts. The turbulence in this model is
  ideally suited to analyze the spectroscopic signatures, such as line
  broadening. The 3-hour long simulation of jets interacting with the
  global solar corona shows plasma responses potentially being observed
  with the upcoming Solar Probe Plus mission.

Title: New Capabilities for Adaptive Mesh Simulation Use within
    FORWARD
Authors: Mathews, N.; Flyer, N.; Gibson, S. E.; Kucera, T. A.;
   Manchester, W.
Bibcode: 2016AGUFMSM32A..05M
Altcode:
  The multiscale nature of the solar corona can pose challenges to
  numerical simulations. Adaptive meshes are often used to resolve
  fine-scale structures, such as the chromospheric-coronal interface
  found in prominences and the transition region as a whole. FORWARD is
  a SolarSoft IDL package designed as a community resource for creating
  a broad range of synthetic coronal observables from numerical models
  and comparing them to data. However, to date its interface with
  numerical simulations has been limited to regular grids. We will
  present a new adaptive-grid interface to FORWARD that will enable
  efficient synthesis of solar observations. This is accomplished
  through the use of hierarchical IDL structures designed to enable
  finding nearest-neighbor points quickly for non-uniform grids. This
  facilitates line-of-sight integrations that can adapt to the unequally
  spaced mesh. We will demonstrate this capability for the Alfven-Wave
  driven SOlar wind Model (AWSOM), part of the Space Weather Modeling
  Framework (SWMF). In addition, we will use it in the context of a
  prominence-cavity model, highlighting new capabilities in FORWARD that
  allow treatment of continuum absorbtion as well as EUV line emission
  via dual populations (chromosphere-corona).

Title: Forecasting CMEs at 1AU with a Flux Rope-Driven Model
Authors: Manchester, W.; Jin, M.; van der Holst, B.; Toth, G.;
   Mullinix, R.; Taktakishvili, A.; Chulaki, A.; Gombosi, T. I.
Bibcode: 2016AGUFMSH11C2249M
Altcode:
  Until recently, operational models of coronal mass ejection (CME)
  propagation omitted magnetic drivers and imposed CMEs with field-free
  flows. While capable of predicting the arrival times of solar wind
  disturbances, such models are incapable of predicting the magnetic
  ejecta of a CME, which is the fundamental driver of large geomagnetic
  storms. Here, we report on a significant advancement in the development
  and delivery of a magnetic flux rope-driven operational CME model
  Eruptive Event Generator Gibson-Low EEGGL that was recently installed
  at the Community Coordinated Modeling Center (CCMC). This new model
  simulates the propagation of CMEs from Sun to 1AU by combining the
  analytical Gibson &amp; Low (GL) flux rope model with the state-of-art
  Alfven Wave Solar Model. Using synoptic magnetcogram and coronagraph
  observations, the model can predict the long-term evolution of the CME
  magnetic fields in interplanetary space. Following the work of Jin et
  al. (2016), we examine case studies of CMEs at 1 AU to illustrate the
  capabilities and limitations of this space weather forecasting tool.

Title: Data Constrained Coronal Mass Ejections in A Global
    Magnetohydrodynamics Model
Authors: Jin, M.; Manchester, W. B.; van der Holst, B.; Sokolov, I.;
   Toth, G.; Mullinix, R. E.; Taktakishvili, A.; Chulaki, A.; Gombosi,
   T. I.
Bibcode: 2016usc..confE.120J
Altcode:
  We present a first-principles-based coronal mass ejection (CME)
  model suitable for both scientific and operational purposes by
  combining a global magnetohydrodynamics (MHD) solar wind model with
  a flux rope-driven CME model. Realistic CME events are simulated
  self-consistently with high fidelity and forecasting capability by
  constraining initial flux rope parameters with observational data from
  GONG, SDO/HMI, SOHO/LASCO, and STEREO/COR. We automate this process
  so that minimum manual intervention is required in specifying the CME
  initial state. With the newly developed data-driven Eruptive Event
  Generator Gibson-Low (EEGGL), we present a method to derive Gibson-Low
  (GL) flux rope parameters through a handful of observational quantities
  so that the modeled CMEs can propagate with the desired CME speeds near
  the Sun. A test result with CMEs launched with different Carrington
  rotation magnetograms are shown. Our study shows a promising result
  for using the first-principles-based MHD global model as a forecasting
  tool, which is capable of predicting the CME direction of propagation,
  arrival time, and ICME magnetic field at 1 AU.

Title: Coronal response to EUV jets modeled with the Alfvén Wave
    Solar Model
Authors: Szente, Judith; Toth, Gabor; Manchester, Ward B., IV; van der
   Holst, Bartholomeus; Landi, Enrico; Gombosi, Tamas; DeVore, Carl R.;
   Antiochos, Spiro K.
Bibcode: 2016usc..confE..72S
Altcode:
  We study the thermodynamics of jet phenomena with the use of multiple
  wavelength SDO-AIA observations [e.g. Adams (2014) and Moore (2015)]
  combined with advanced numerical simulations made with AWSoM coronal
  model [van der Holst (2014)]. AWSoM provides a fully three-dimensional,
  magnetohydrodynamic description of the solar atmosphere heated by the
  dissipation of kinetic Alfvén waves in a self-consistent manner. In
  addition, the model's multi-species thermodynamics with electron
  heat conduction provides for the accurate construction of synthetic
  line-of-sight images of phenomena. We implement our jets in the solar
  wind with a magnetic dipole twisted about axis, resulting in EUV jets
  similar in topology and dynamics as being observed. We show that the
  coronal atmosphere responds at a large-scale as torsional Alfvén waves
  propagate into the outer corona (up to 24 solar radii and 40 degrees in
  latitude), introduced by the small-scale eruptive reconnection events
  at the footpoint of the jet.

Title: Threaded-Field-Lines Model for the Low Solar Corona Powered
    by the Alfven Wave Turbulence
Authors: Sokolov, Igor V.; van der Holst, Bart; Manchester, Ward B.;
   Ozturk, Doga Can Su; Szente, Judit; Taktakishvili, Aleksandre; Tóth,
   Gabor; Jin, Meng; Gombosi, Tamas I.
Bibcode: 2016arXiv160904379S
Altcode:
  We present an updated global model of the solar corona, including
  the transition region. We simulate the realistic tree-dimensional
  (3D) magnetic field using the data from the photospheric magnetic
  field measurements and assume the magnetohydrodynamic (MHD) Alfvén
  wave turbulence and its non-linear dissipation to be the only source
  for heating the coronal plasma and driving the solar wind. In closed
  field regions the dissipation efficiency in a balanced turbulence
  is enhanced. In the coronal holes we account for a reflection of
  the outward propagating waves, which is accompanied by generation of
  weaker counter-propagating waves. The non-linear cascade rate degrades
  in strongly imbalanced turbulence, thus resulting in colder coronal
  holes. The distinctive feature of the presented model is the description
  of the low corona as almost-steady-state low-beta plasma motion and
  heat flux transfer along the magnetic field lines. We trace the magnetic
  field lines through each grid point of the lower boundary of the global
  corona model, chosen at some heliocentric distance, $R=R_{b}\sim1.1\
  R_\odot$ well above the transition region. One can readily solve the
  plasma parameters along the magnetic field line from 1D equations for
  the plasma motion and heat transport together with the Alfvén wave
  propagation, which adequately describe physics within the heliocentric
  distances range, $R_{\odot}&lt;R&lt;R_{b}$, in the low solar corona. By
  interfacing this threaded-field-lines model with the full MHD global
  corona model at $r=R_{b}$, we find the global solution and achieve a
  faster-than-real-time performance of the model on $\sim200$ cores.

Title: 3-D Flux Rope Modeling of CME-like Plasma Dynamics in the
    PBEX HelCat Experiment
Authors: Fisher, Dustin Mark; Zhang, Y.; Wallace, B.; Gilmore, M.;
   Manchester, W.; Arge, C. N.
Bibcode: 2016shin.confE..51F
Altcode:
  The Plasma Bubble Expansion Experiment (PBEX) [1] at UNM uses a
  plasma gun to launch jet and spheromak magnetic configurations into
  the Helicon-Cathode (HelCat) [2] basic plasma device. The short
  scale lengths and dense, collisional nature of the plasma allow
  for a parameter regime and dynamics that greatly match those found
  in the lower density plasma of the solar wind. This provides unique
  experimental access to studying possible CME propagation into the solar
  wind. Moreover, the numerous diagnostic capabilities of HelCat allow
  for validation of numerical codes that aim to make predictive models
  of real-time solar events. <P />Preliminary modeling and analysis
  of the PBEX experiment is presented using the highly-developed 3-D,
  MHD, BATS-R-US [3,4] solar coronal model of the Space Weather Modeling
  Framework (SWMF) [3,5] code from the University of Michigan. BATS-R-US
  employs an adaptive mesh refinement (AMR) grid that enables the
  capture and resolution of shock structures and current sheets which
  can subsequently be compared to high-resolution magnetogram data. Such
  modeling may provide insights into the role of heating and reconnection
  in CME-like events. <P />Initial modeling uses the Titov-Demoulin
  (TD)[6] flux rope model to mimic plasma bubbles launched from the
  PBEX gun. A spheromak-based flux model may also be used in the ongoing
  modeling.

Title: Achieving Forecasts in the Thermosphere and Ionosphere with
    Lead Times of a Few Days
Authors: Mannucci, A. J.; Meng, X.; Verkhoglyadova, O. P.; Tsurutani,
   B.; Manchester, W.; Sharma, S.
Bibcode: 2015AGUFMSH11A2374M
Altcode:
  Forecasting space weather requires the development of
  first-principles-based models for the coupled Sun-Earth System. To
  achieve lead times of a few days for disturbances in planetary
  thermospheres and ionospheres, models of the solar wind propagating
  through the heliosphere are required. An active research community
  has achieved a suite of models that describe conditions within, and
  coupling between, the solar wind, the Earth's magnetosphere and the
  ionosphere. At least one version of each model in the suite is available
  for broad community use and investigation. While these models represent
  an important step towards the goal of achieving accurate space weather
  forecasts, it is recognized that certain physical processes are not
  represented in these models, with unknown impact on the forecasts. We
  suggest an approach towards improved space weather forecasts that
  emphasizes model evaluation techniques, providing detailed information
  on how the physical processes represented in the models affect forecasts
  based on those models. Such detailed information permits the models to
  be used for investigating science questions, and permits observations
  to be the basis for improving the models and increasing scientific
  understanding. In this talk, we present upper atmosphere forecasting
  results using community models of the coupled Sun-Earth system. We
  describe our approach to analyzing the physics of ionospheric storms
  as represented in the Global Ionosphere Thermosphere Model developed at
  the University of Michigan. Such analysis involves both an approach to
  model diagnostics and the use of a comprehensive set of observations. We
  compare forecast results for high-speed solar wind stream storms and
  storms initiated by solar coronal mass ejections. First-principle
  and empirically based approaches to coupling between the solar wind
  and ionosphere are compared. These comparisons provide insight into
  the strengths and limitations, and areas for future improvement, of
  first-principles models as they are used to forecast the Sun-Earth
  interaction.

Title: Modeling AWSoM CMEs with EEGGL: A New Approach for Space
    Weather Forecasting
Authors: Jin, M.; Manchester, W.; van der Holst, B.; Sokolov, I.;
   Toth, G.; Vourlidas, A.; de Koning, C. A.; Gombosi, T. I.
Bibcode: 2015AGUFMSH43C..02J
Altcode:
  The major source of destructive space weather is coronal mass ejections
  (CMEs). However, our understanding of CMEs and their propagation in the
  heliosphere is limited by the insufficient observations. Therefore,
  the development of first-principals numerical models plays a vital
  role in both theoretical investigation and providing space weather
  forecasts. Here, we present results of the simulation of CME propagation
  from the Sun to 1AU by combining the analytical Gibson &amp; Low (GL)
  flux rope model with the state-of-art solar wind model AWSoM. We also
  provide an approach for transferring this research model to a space
  weather forecasting tool by demonstrating how the free parameters of
  the GL flux rope can be prescribed based on remote observations via
  the new Eruptive Event Generator by Gibson-Low (EEGGL) toolkit. This
  capability allows us to predict the long-term evolution of the CME
  in interplanetary space. We perform proof-of-concept case studies to
  show the capability of the model to capture physical processes that
  determine CME evolution while also reproducing many observed features
  both in the corona and at 1 AU. We discuss the potential and limitations
  of this model as a future space weather forecasting tool.

Title: Simulation of Active-Region-Scale Flux Emergence
Authors: Manchester, W.; van der Holst, B.
Bibcode: 2015AGUFMSH13A2433M
Altcode:
  Shear flows long observed in solar active regions are now understood
  to be a consequence of the Lorentz force that develops from a complex
  interaction between magnetic fields and the thermal pressure of the
  Sun's gravitationally stratified atmosphere. The shearing motions
  transport magnetic flux and energy from the submerged portion of
  the field to the corona providing the necessary energy for flares,
  filament eruptions and CMEs. To further examine this shearing process,
  we simulate flux emergence on the scale of active regions with a
  large-scale model of the near surface convection zone constructed on
  an adaptive spherical grid. This model is designed to simulate flux
  emerging on the scale of active regions from a depth of 30 Mm. Here,
  we show results of a twisted flux rope emerging through the hierarchy
  of granular convection, and examine the flow patterns that arise as
  the flux approaches the photosphere. We show how these organized flows
  driven by the Lorentz force cause the coronal field evolve to a highly
  non-potential configuration capable of driving solar eruptions such
  as CMEs and flares.

Title: The Physics of CME Propagation
Authors: Manchester, W.
Bibcode: 2015AGUFMSH42A..03M
Altcode:
  Coronal mass ejections (CMEs) have been the subject of intense
  investigation since their discovery more than forty years ago, which
  have produced enormous advances in our understanding of the structure
  and dynamics of CMEs. Here, we examine the results of numerical
  simulations to identify a wide range of physical processes that govern
  the interaction of CMEs with the corona and the larger heliosphere. We
  focus on processes which determine the bulk transport of plasma
  and magnetic flux including kinematic effects, magnetohydrodynamic
  instabilities and magnetic reconnection. We compare simulation
  results to remote-sensing observations and in-situ measurements to
  both verify the models and explain a number of observed properties of
  interplanetary CMEs.

Title: Dynamics of Polar Jets from the Chromosphere to the Corona:
    Mass, Momentum and Energy Transfer
Authors: Szente, J.; Toth, G.; Manchester, W.; van der Holst, B.;
   Landi, E.; DeVore, C. R.; Gombosi, T. I.
Bibcode: 2015AGUFMSH23D..05S
Altcode:
  Coronal jets, routinely observed by multiple instruments at
  multiple wavelengths, provide a unique opportunity to understand
  the relationships between magnetic field topology, reconnection, and
  solar wind heating and acceleration. We simulate coronal jets with the
  Alfvén Wave Solar Model (AWSoM) [van der Holst (2014)] and focus our
  study on the thermodynamical evolution of the plasma. AWSoM solves
  the two-temperature MHD equations with electron heat conduction,
  which not only addresses the thermodynamics of individual species,
  but also allows for the construction of synthetic images from the EUV
  and soft X-ray wavelength range. Our jet model takes the form of a
  slowly rotating bipole field imbedded in the open magnetic field of
  a coronal hole; a topology suggested by observations. We follow the
  formation and evolution of polar jets starting from the chromosphere
  and extending into the outer corona. The simulations show small-scale
  eruptive reconnection events that self-consistently heat and accelerate
  the solar wind. Our results provide a quantitative comparison to
  observations made in the EUV and X-ray spectrum.

Title: New Publicly Available EEGGL Tool for Simulating Coronal
    Mass Ejections.
Authors: Sokolov, I.; Manchester, W.; van der Holst, B.; Gombosi,
   T. I.; Jin, M.; Mullinix, R.; Taktakishvili, A.; Chulaki, A.; Toth, G.
Bibcode: 2015AGUFMSH21B2403S
Altcode:
  We present and demonstrate a new tool, EEGGL (Eruptive Event Generator
  using Gibson-Low configuration) for simulating CMEs (Coronal Mass
  Ejections). CMEs are among the most significant space weather events,
  producing the radiation hazards (via the diffuse shock acceleration
  of the Solar Energetic Particles - SEPs), the interplanetary shock
  waves as well as the geomagnetic activity due to the drastic changes of
  the interplanetary magnetic field within the "magnetic clouds" ("flux
  ropes"). Some of this effects may be efficiently simulated using the
  "cone model", which is employed in the real-time simulations of the
  ongoing CMEs at the NASA-Goddard Space Flight Center. The cone model
  provides a capability to predict the location, time, width and shape of
  the hydrodynamic perturbation in the upper solar corona (at ~0.1 AU),
  which can be used to drive the heliospheric simulation (with the ENLIL
  code, for example). At the same time the magnetic field orientation
  in this perturbation is uncertain within the cone model, which limits
  the capability of the geomagnetic activity forecast. The new EEGGL
  tool http://ccmc.gsfc.nasa.gov/analysis/EEGGL/recently developed at
  the Goddard Space Flight Center in collaboration with the University
  of Michigan provides a new capability for both evaluating the magnetic
  field configuration resulting from the CME and tracing the CME through
  the solar corona. In this way not only the capability to simulate the
  magnetic field evolution at 1 AU may be achieved, but also the more
  extensive comparison with the CME observations in the solar corona may
  be achieved. Based on the magnetogram and evaluation of the CME initial
  location and speed, the user may choose the active region from which
  the CME originates and then the EEGGL tools provides the parameters
  of the Gibson-Low magnetic configuration to parameterize the CME. The
  recommended parameters may be used then to drive the simulation of CME
  propagation from the low solar corona to 1 AU using the global code
  for simulating the solar corona and inner heliosphere. The Community
  Coordinated Modeling Center (CCMC) provides the capability for CME
  runs-on-request, to the heliophysics community.

Title: Heliospheric Propagation of Coronal Mass Ejections: A Review
Authors: Lugaz, Noé; Farrugia, Charles; Schwadron, Nathan; Manchester,
   Ward B.
Bibcode: 2015IAUGA..2237318L
Altcode:
  Coronal mass ejections (CMEs) are the most energetic events from the
  Sun and the major driver of intense geomagnetic activity. Traditionally,
  most research has focused on understanding the causes of CME initiation
  and the specificities of the interaction between CMEs and Earth's
  magnetosphere. In-between these two domains, CMEs propagate in the
  heliosphere, interacting with the solar wind and other transient and
  corotating structures. The heliospheric propagation of CMEs can now
  be directly imaged remotely, making it possible to directly compare
  solar and coronal properties with CME properties measured in situ
  near Earth. In addition, numerical simulations can be used to get a
  more complete, 3-D view of CMEs. Here, I will review progress made
  in the past decade in our understanding of CME propagation and how
  it affects the CME properties as measured near Earth. In particular,
  I will discuss CME radial expansion, CME deflection and rotation as
  well as the interaction of successive CMEs and the interaction of a
  CME with corotating solar wind structures.

Title: A Steady-state Picture of Solar Wind Acceleration and Charge
    State Composition Derived from a Global Wave-driven MHD Model
Authors: Oran, R.; Landi, E.; van der Holst, B.; Lepri, S. T.;
   Vásquez, A. M.; Nuevo, F. A.; Frazin, R.; Manchester, W.; Sokolov,
   I.; Gombosi, T. I.
Bibcode: 2015ApJ...806...55O
Altcode: 2014arXiv1412.8288O
  The higher charge states found in slow (&lt;400 km s<SUP>-1</SUP>)
  solar wind streams compared to fast streams have supported the
  hypothesis that the slow wind originates in closed coronal loops
  and is released intermittently through reconnection. Here we examine
  whether a highly ionized slow wind can also form along steady and open
  magnetic field lines. We model the steady-state solar atmosphere using
  the Alfvén Wave Solar Model (AWSoM), a global MHD model driven by
  Alfvén waves, and apply an ionization code to calculate the charge
  state evolution along modeled open field lines. This constitutes the
  first charge state calculation covering all latitudes in a realistic
  magnetic field. The ratios {{O}<SUP>+7</SUP>}/{{O}<SUP>+6</SUP>}
  and {{C}<SUP>+6</SUP>}/{{C}<SUP>+5</SUP>} are compared to in situ
  Ulysses observations and are found to be higher in the slow wind, as
  observed; however, they are underpredicted in both wind types. The
  modeled ion fractions of S, Si, and Fe are used to calculate
  line-of-sight intensities, which are compared to Extreme-ultraviolet
  Imaging Spectrometer (EIS) observations above a coronal hole. The
  agreement is partial and suggests that all ionization rates are
  underpredicted. Assuming the presence of suprathermal electrons improved
  the agreement with both EIS and Ulysses observations; importantly,
  the trend of higher ionization in the slow wind was maintained. The
  results suggest that there can be a sub-class of slow wind that is
  steady and highly ionized. Further analysis shows that it originates
  from coronal hole boundaries (CHBs), where the modeled electron
  density and temperature are higher than inside the hole, leading to
  faster ionization. This property of CHBs is global and observationally
  supported by EUV tomography.

Title: Forecasting ionospheric space weather with applications to
    satellite drag and radio wave communications and scintillation
Authors: Mannucci, Anthony J.; Tsurutani, Bruce T.; Verkhoglyadova,
   Olga P.; Meng, Xing; Pi, Xiaoqing; Kuang, Da; Wang, Chunming; Rosen,
   Gary; Ridley, Aaron; Lynch, Erin; Sharma, Surja; Manchester, Ward B.;
   van der Holst, Bart
Bibcode: 2015TESS....111202M
Altcode:
  The development of quantitative models that describe physical
  processes from the solar corona to the Earth’s upper atmosphere
  opens the possibility of numerical space weather prediction with a
  lead-time of a few days. Forecasting solar wind-driven variability
  in the ionosphere and thermosphere poses especially stringent
  tests of our scientific understanding and modeling capabilities, in
  particular of coupling processes to regions above and below. We will
  describe our work with community models to develop upper atmosphere
  forecasts starting with the solar wind driver. A number of phenomena
  are relevant, including high latitude energy deposition, its impact
  on global thermospheric circulation patterns and composition, and
  global electrodynamics. Improved scientific understanding of this
  sun to Earth interaction ultimately leads to practical benefits. We
  will focus on two ways the upper atmosphere affects life on Earth:
  by changing satellite orbits, and by interfering with long-range
  radio communications. Challenges in forecasting these impacts will be
  addressed, with a particular emphasis on the physical bases for the
  impacts, and how they connect upstream to the sun and the heliosphere.

Title: Counter-streaming alpha proton plasmas in an eroding magnetic
cloud: new insights into space plasma evolution from Wind
Authors: Szente, J.; Toth, G.; Manchester, W.; van der Holst, B.;
   Landi, E.; DeVore, C. R.; Gombosi, T. I.
Bibcode: 2014AGUFMSH23D..05S
Altcode:
  Coronal jets, routinely observed by multiple instruments at
  multiple wavelengths, provide a unique opportunity to understand
  the relationships between magnetic field topology, reconnection, and
  solar wind heating and acceleration. We simulate coronal jets with the
  Alfvén Wave Solar Model (AWSoM) [van der Holst (2014)] and focus our
  study on the thermodynamical evolution of the plasma. AWSoM solves
  the two-temperature MHD equations with electron heat conduction,
  which not only addresses the thermodynamics of individual species,
  but also allows for the construction of synthetic images from the EUV
  and soft X-ray wavelength range. Our jet model takes the form of a
  slowly rotating bipole field imbedded in the open magnetic field of
  a coronal hole; a topology suggested by observations. We follow the
  formation and evolution of polar jets starting from the chromosphere
  and extending into the outer corona. The simulations show small-scale
  eruptive reconnection events that self-consistently heat and accelerate
  the solar wind. Our results provide a quantitative comparison to
  observations made in the EUV and X-ray spectrum.

Title: Coronal Hole Boundaries as Source Regions of a Steady
Slow Solar Wind: Global Modeling of Charge State Composition and
    Sun-to-Earth Observations
Authors: Oran, R.; Landi, E.; van der Holst, B.; Lepri, S. T.;
   Manchester, W.; Frazin, R. A.; Nuevo, F.; Vásquez, A. M.; Sokolov,
   I.; Gombosi, T. I.
Bibcode: 2014AGUFMSH33A4122O
Altcode:
  We combine the results from a global MHD model of the solar atmosphere
  with a charge state evolution code in order to predict the large-scale
  variation of charge state composition in the fast and slow solar wind
  during solar minimum. The model captures the well-known increase in
  charge state ratios C+6/ C+5 and O+7/O+6 in the slow wind, inline with
  Ulysses observations. We present a theoretical picture explaining
  the formation of these increases, which are related to regions of
  higher electron density and temperature near the boundaries of coronal
  holes. We verify the existence of these regions using a 3D tomographic
  reconstruction of the lower corona. This work establishes that a steady
  slow wind flowing along open magnetic field lines can carry high charge
  states without invoking reconnection with closed field regions. This
  subset of slow wind can play a role explaining the properties of the
  non-steady slow wind, and complement dynamic models of slow solar
  wind formation.

Title: Ensemble Space Weather Forecasting with the SWMF
Authors: Frazin, R. A.; van der Holst, B.; Manchester, W.; Sokolov,
   I.; Huang, Z.; Gombosi, T. I.
Bibcode: 2014AGUFMSH53A4207F
Altcode:
  An accurate, physics-based model of the heliosphere that extends
  from the Sun to the Earth and beyond is the ``holy grail'' of space
  weather forecasting. Global models that start in the corona (or below)
  are driven by representations of the full-Sun photospheric magnetic
  field. Traditionally, the full-Sun magnetic field has been provided
  by synoptic magnetograms, which are created over a 28 day period
  and are not an accurate representation of the magnetic field at any
  given time. Recently, several groups have been producing so-called
  ``synchronic maps,'' which fuse magnetograms and models including
  differential rotation, meridional transport and diffusion to create
  time-dependent full-Sun magnetic field maps. Here, we include a variety
  of synchronic and synoptic maps to create an ensemble space weather
  model and report on the results.

Title: Simulating CME Eruptions from Active Regions
Authors: Manchester, W.; van der Holst, B.
Bibcode: 2014AGUFMSH51E..03M
Altcode:
  Fast coronal mass ejections (CMEs) typically erupt from the filament
  channels of active regions where the magnetic field is in a highly
  non potential state. In this talk, we discuss two numerical models
  under development that will simulate the evolution of active regions
  and the buildup of magnetic energy that leads to filament eruptions
  and CMEs. The first model, the so called regional model simulates
  the area of an active region in a domain that extends from just
  above the photosphere at its base to a height of 100 Mm in the low
  corona. The physics of this model is extended magnetohydrodynamics
  (MHD), which includes such physical processes as field aligned heat
  conduction, radiative losses, and tabular equation of state that
  allow for a self-consistent treatment of the atmosphere including
  the transition region. For this model, boundary conditions for the
  magnetic field fields are specified directly from HMI vector magnetogram
  observations. The second model addresses the buoyant rise of magnetic
  flux from the convection zone through the photosphere to allow for the
  self consistent formation and evolution of active regions that leads
  to the buildup of magnetic free energy. We compare results from this
  second model to SDO/HMI observations of the 7 January 2014 events to
  show that the simulation has captured the basic physics of magnetic
  field evolution an energy build up necessary for large-scale eruptions.

Title: Global MHD Simulation of the Coronal Mass Ejection on 2011
March 7: from Chromosphere to 1 AU
Authors: Jin, M.; Manchester, W.; van der Holst, B.; Sokolov, I.;
   Toth, G.; Vourlidas, A.; de Koning, C. A.; Gombosi, T. I.
Bibcode: 2014AGUFMSH43A4176J
Altcode:
  Performing realistic simulations of solar eruptions and validating
  those simulations with observations are important goals in order
  to achieve accurate space weather forecasts. Here, we perform and
  analyze results of a global magnetohydrodyanmic (MHD) simulation of the
  fast coronal mass ejection (CME) that occurred on 2011 March 7. The
  simulation is made using the newly developed Alfven Wave Solar Model
  (AWSoM), which describes the background solar wind starting from the
  upper chromosphere and expands to 24 Rs. Coupling of AWSoM to an inner
  heliosphere (IH) model with the Space Weather Modeling Framework (SWMF)
  extends the total domain beyond the orbit of Earth. Physical processes
  included in the model are multi-species thermodynamics, electron heat
  conduction (both collisional and collisionless formulations), optically
  thin radiative cooling, and Alfven-wave pressure that accelerates
  the solar wind. The Alfven-wave description is physically consistent,
  including non-WKB reflection and physics-based apportioning of turbulent
  dissipative heating to both electrons and protons. Within this model,
  we initiate the CME by using the Gibson-Low (GL) analytical flux rope
  model and follow its evolution for days, in which time it propagates
  beyond 1 AU. A comprehensive validation study is performed using
  remote as well as in-situ observations from SDO, SOHO, STEREOA/B,
  and OMNI. Our results show that the new model can reproduce many
  of the observed features near the Sun (e.g., CME-driven EUV waves,
  deflection of the flux rope from the coronal hole, "double-front"
  in the white light images) and in the heliosphere (e.g., CME-CIR
  interaction, shock properties at 1 AU). The CME-driven shock arrival
  time is within 1 hour of the observed arrival time, and nearly all the
  in-situ parameters are correctly simulated, which suggests the global
  MHD model as a powerful tool for the space weather forecasting.

Title: Magnetic Flux Erosion and Redistribution during CME Propagation
Authors: Lavraud, B.; Ruffenach, A.; Manchester, W.; Farrugia, C. J.;
   Demoulin, P.; Dasso, S.; Sauvaud, J. A.; Rouillard, A. P.; Foullon,
   C.; Owens, M. J.; Savani, N.; Kajdic, P.; Luhmann, J. G.; Galvin, A. B.
Bibcode: 2014AGUFMSH22A..01L
Altcode:
  We will review recent works which highlight the occurrence of magnetic
  flux erosion and redistribution at the front of coronal mass ejections
  (when they have the structure of a well-defined magnetic cloud). Two
  main processes have been found and will be presented. The first comes
  from the occurrence of magnetic reconnection between the magnetic
  cloud and its sheath ahead, leading to magnetic flux erosion and
  redistribution, with associated large scale topological changes. The
  second may occur when dense filament material in the coronal mass
  ejection pushes its way through the structure and comes in direct
  contact with the shocked plasma in the sheath ahead. This leads to
  diverging non-radial flows in front of the CME which transport poloidal
  flux of the flux rope to the sides of the magnetic cloud.

Title: Predicting ICME Magnetic Fields with a Numerical Flux Rope
    Model
Authors: Manchester, W.; van der Holst, B.; Sokolov, I.
Bibcode: 2014AGUFMSH21C4137M
Altcode:
  Coronal mass ejections (CMEs) are a dramatic manifestation of solar
  activity that release vast amounts of plasma into the heliosphere,
  and have many effects on the interplanetary medium and on planetary
  atmospheres, and are the major driver of space weather. CMEs occur with
  the formation and expulsion of large-scale flux ropes from the solar
  corona, which are routinely observed in interplanetary space. Simulating
  and predicting the structure and dynamics of these ICME magnetic fields
  is essential to the progress of heliospheric science and space weather
  prediction. We combine observations made by different observing
  techniques of CME events to develop a numerical model capable of
  predicting the magnetic field of interplanetary coronal mass ejections
  (ICMES). Photospheric magnetic field measurements from SOHO/MDI and
  SDO/HMI are used to specify a coronal magnetic flux rope that drives
  the CMEs. We examine halo CMEs events that produced clearly observed
  magnetic clouds at Earth and present our model predictions of these
  events with an emphasis placed on the z component of the magnetic
  field. Comparison of the MHD model predictions with coronagraph
  observations and in-situ data allow us to robustly determine the
  parameters that define the initial state of the driving flux rope,
  thus providing a predictive model.

Title: Forecasting Ionospheric Space Weather Due To High Speed Streams
Authors: Mannucci, A. J.; Verkhoglyadova, O. P.; Meng, X.; Tsurutani,
   B. T.; Pi, X.; Lynch, E. M.; Sharma, S.; Ridley, A. J.; Manchester,
   W.; Wang, C.; Rosen, G.
Bibcode: 2014AGUFMSA12A..08M
Altcode:
  The development of quantitative models that describe physical processes
  from the Solar corona to the Earth's upper atmosphere opens the
  possibility of numerical space weather forecasting with a lead time of
  a few days. We will describe our work with community models to develop
  ionospheric forecasts starting with the solar wind driver. Our current
  focus is the daytime ionospheric response to high-speed solar wind
  streams that are prevalent during the declining phase of the solar
  cycle. A number of challenges are addressed, including high latitude
  energy deposition and its impact on global thermospheric circulation
  patterns and composition. The degree to which forecasts are successful
  depends on the manner in which Alfvenic solar wind variability drives
  the ionospheric response. Large-scale and small-scale magnetospheric
  processes are important to consider, including the role of particle
  precipitation in depositing energy into the thermosphere and in changing
  ionospheric conductivities through increased ionization. Accurate
  forecasts require that we address the following question: what are the
  impacts of (less predictable) small-scale processes in determining the
  large-scale daytime ionospheric response, versus the role of larger
  scale magnetospheric processes that may be easier to predict? We
  will compare model-based forecasts with a variety of satellite and
  ground-based data sources to assess the fidelity of physical processes
  represented in the models. Outstanding science questions that are
  relevant to forecasts are described.

Title: Simulation of magnetic cloud erosion during propagation
Authors: Manchester, W. B.; Kozyra, J. U.; Lepri, S. T.; Lavraud, B.
Bibcode: 2014JGRA..119.5449M
Altcode:
  We examine a three-dimensional (3-D) numerical magnetohydrodynamic (MHD)
  simulation describing a very fast interplanetary coronal mass ejection
  (ICME) propagating from the solar corona to 1 AU. In conjunction
  with its high speed, the ICME evolves in ways that give it a unique
  appearance at 1 AU that does not resemble a typical ICME. First,
  as the ICME decelerates far from the Sun in the solar wind, filament
  material at the back of the flux rope pushes its way forward through the
  flux rope. Second, diverging nonradial flows in front of the filament
  transport poloidal flux of the rope to the sides of the ICME. Third,
  the magnetic flux rope reconnects with the interplanetary magnetic
  field (IMF). As a consequence of these processes, the flux rope
  partially unravels and appears to evolve to an entirely unbalanced
  configuration. At the same time, filament material at the base of the
  flux rope moves forward and comes in direct contact with the shocked
  plasma in the CME sheath. We find evidence that such remarkable behavior
  has actually occurred when we examine a very fast CME that erupted
  from the Sun on 2005 January 20. In situ observations of this event
  near 1 AU show very dense cold material impacting the Earth following
  immediately behind the CME sheath. Charge state analysis shows this
  dense plasma is filament material. Consistent with the simulation, we
  find the poloidal flux (B<SUB>z</SUB>) to be entirely unbalanced, giving
  the appearance that the flux rope has eroded. The dense solar filament
  material and unbalanced positive IMF B<SUB>z</SUB> produced a number
  of anomalous features in a moderate magnetic storm already underway,
  which are described in a companion paper by Kozyra et al. (2014).

Title: Solar filament impact on 21 January 2005: Geospace consequences
Authors: Kozyra, J. U.; Liemohn, M. W.; Cattell, C.; De Zeeuw, D.;
   Escoubet, C. P.; Evans, D. S.; Fang, X.; Fok, M. -C.; Frey, H. U.;
   Gonzalez, W. D.; Hairston, M.; Heelis, R.; Lu, G.; Manchester, W. B.;
   Mende, S.; Paxton, L. J.; Rastaetter, L.; Ridley, A.; Sandanger,
   M.; Soraas, F.; Sotirelis, T.; Thomsen, M. W.; Tsurutani, B. T.;
   Verkhoglyadova, O.
Bibcode: 2014JGRA..119.5401K
Altcode:
  On 21 January 2005, a moderate magnetic storm produced a number of
  anomalous features, some seen more typically during superstorms. The
  aim of this study is to establish the differences in the space
  environment from what we expect (and normally observe) for a
  storm of this intensity, which make it behave in some ways like a
  superstorm. The storm was driven by one of the fastest interplanetary
  coronal mass ejections in solar cycle 23, containing a piece of the
  dense erupting solar filament material. The momentum of the massive
  solar filament caused it to push its way through the flux rope as
  the interplanetary coronal mass ejection decelerated moving toward
  1 AU creating the appearance of an eroded flux rope (see companion
  paper by Manchester et al. (2014)) and, in this case, limiting the
  intensity of the resulting geomagnetic storm. On impact, the solar
  filament further disrupted the partial ring current shielding in
  existence at the time, creating a brief superfountain in the equatorial
  ionosphere—an unusual occurrence for a moderate storm. Within 1
  h after impact, a cold dense plasma sheet (CDPS) formed out of the
  filament material. As the interplanetary magnetic field (IMF) rotated
  from obliquely to more purely northward, the magnetotail transformed
  from an open to a closed configuration and the CDPS evolved from
  warmer to cooler temperatures. Plasma sheet densities reached tens
  per cubic centimeter along the flanks—high enough to inflate the
  magnetotail in the simulation under northward IMF conditions despite
  the cool temperatures. Observational evidence for this stretching was
  provided by a corresponding expansion and intensification of both the
  auroral oval and ring current precipitation zones linked to magnetotail
  stretching by field line curvature scattering. Strong Joule heating in
  the cusps, a by-product of the CDPS formation process, contributed to
  an equatorward neutral wind surge that reached low latitudes within 1-2
  h and intensified the equatorial ionization anomaly. Understanding the
  geospace consequences of extremes in density and pressure is important
  because some of the largest and most damaging space weather events
  ever observed contained similar intervals of dense solar material.

Title: Global Magnetohydrodynamics Simulation of the Coronal Mass
Ejection on 2011 March 7: from Chromosphere to 1 AU
Authors: Jin, Meng; Manchester, W. B.; van der Holst, B.; Sokolov,
   I.; Toth, G.; Vourlidas, A.; de Koning, C.; Gombosi, T. I.
Bibcode: 2014shin.confE..10J
Altcode:
  Performing realistic simulations of solar eruptions and validating
  those simulations with observations are important goals in order to
  achieve accurate space weather forecasts. Here, we analyze results
  of a global magnetohydrodyanmic (MHD) simulation of the fast coronal
  mass ejection (CME) that occurred on 2011 March 7. The simulation is
  made using the newly developed Alfven Wave Solar Model (AWSoM), which
  describes the background solar wind starting from the upper chromosphere
  and expends to 24 Rs. Coupling of AWSoM to an inner heliosphere (IH)
  model with the Space Weather Modeling Framework extends the total domain
  beyond the orbit of Earth. Physical processes included in the model are
  multi-species thermodynamics, electron heat conduction (both collisional
  and collisionless formulation), optically thin radiative cooling and
  Alfven-wave pressure that accelerates the solar wind. The Alfven-wave
  description is physically self-consistent, including non-WKB reflection
  and physics-based apportioning of turbulent dissipative heating to both
  electrons and protons. Within this model, we initiate the CME by using
  the Gibson-Low (GL) analytical flux rope model and follow its evolution
  for days, in which time it propagates beyond 1 AU. A comprehensive
  validation study is performed using remote as well as the in situ
  observations from SDO, SOHO, STEREOA/B, and OMNI. Our results show
  that the new model can reproduce many of the observed features near
  the Sun (e.g., CME-driven EUV waves, deflection of the flux rope from
  the coronal hole, double-front in the white light images) and in the
  heliosphere (e.g., CME-CIR interaction, shock properties at 1 AU). By
  fitting the CME speeds near the Sun with observations, the CME-driven
  shock arrival time is within 1 hour of the observed arrival time and
  all the in situ parameters are correctly simulated, which suggests the
  global MHD model as a powerful tool for the space weather forecasting.

Title: Charge State Evolution in the Fast and Slow Wind Predicted
    by a Global Wave-Driven Solar Model
Authors: Oran, Rona; Landi, Enrico; van der Holst, Bart; Lepri, Susan;
   Vásquez, Alberto; Nuevo, Federico; Frazin, Richard; Manchester,
   Ward; Sokolov, Igor; Gombosi, Tamas
Bibcode: 2014shin.confE..66O
Altcode:
  The mechanisms responsible for the formation of the slow solar wind are
  a subject of vigorous debate in the heliospheric community. The heavy
  ion charge state composition measured in-situ at 1AU and beyond depend
  on the plasma conditions along the wind trajectory close to the Sun,
  and are known to be significantly different when measured in either
  the fast or slow solar wind. As such, heavy ion charge states have
  played an important role in testing the various theories concerning
  the formation of the fast and slow wind, and in determining the source
  region of the slow solar wind. <P />We will present results from a
  global MHD model of the solar atmosphere, in which the wind is heated
  and accelerated by Alfven waves. The global model results are used to
  drive a charge state evolution code along open magnetic field lines at
  all heliographic latitudes. The resulting charge state distributions of
  several ions are compared to in-situ Ulysses measurements at 1-2AU as
  well as to high resolution spectra observed in the lower corona. We
  find that the large scale latitudinal variation in charge states
  is captured by the model. In particular, the model can reproduce
  and explain the increase in the O+7/O+6, C+6/C+5 ratios in the slow
  (steady) solar wind compared to the fast wind. We demonstrate that these
  increases are associated with a higher plasma density at the base of
  open field lines whose foot-points are located near the boundary of
  the coronal holes. We show that this density enhancement as predicted
  by the model is consistent with EUV tomographic reconstructions of the
  lower corona. We discuss the possible interpretations and implications
  of our results to our understanding of solar wind formation.

Title: Alfvén Wave Solar Model (AWSoM): Coronal Heating
Authors: van der Holst, B.; Sokolov, I. V.; Meng, X.; Jin, M.;
   Manchester, W. B., IV; Tóth, G.; Gombosi, T. I.
Bibcode: 2014ApJ...782...81V
Altcode: 2013arXiv1311.4093V
  We present a new version of the Alfvén wave solar model, a global model
  from the upper chromosphere to the corona and the heliosphere. The
  coronal heating and solar wind acceleration are addressed with
  low-frequency Alfvén wave turbulence. The injection of Alfvén
  wave energy at the inner boundary is such that the Poynting flux is
  proportional to the magnetic field strength. The three-dimensional
  magnetic field topology is simulated using data from photospheric
  magnetic field measurements. This model does not impose open-closed
  magnetic field boundaries; those develop self-consistently. The
  physics include the following. (1) The model employs three different
  temperatures, namely the isotropic electron temperature and the
  parallel and perpendicular ion temperatures. The firehose, mirror,
  and ion-cyclotron instabilities due to the developing ion temperature
  anisotropy are accounted for. (2) The Alfvén waves are partially
  reflected by the Alfvén speed gradient and the vorticity along the
  field lines. The resulting counter-propagating waves are responsible
  for the nonlinear turbulent cascade. The balanced turbulence due to
  uncorrelated waves near the apex of the closed field lines and the
  resulting elevated temperatures are addressed. (3) To apportion the
  wave dissipation to the three temperatures, we employ the results
  of the theories of linear wave damping and nonlinear stochastic
  heating. (4) We have incorporated the collisional and collisionless
  electron heat conduction. We compare the simulated multi-wavelength
  extreme ultraviolet images of CR2107 with the observations from
  STEREO/EUVI and the Solar Dynamics Observatory/AIA instruments. We
  demonstrate that the reflection due to strong magnetic fields in the
  proximity of active regions sufficiently intensifies the dissipation
  and observable emission.

Title: Geo-effectiveness and radial dependence of magnetic cloud
    erosion by magnetic reconnection
Authors: Lavraud, Benoit; Ruffenach, Alexis; Rouillard, Alexis P.;
   Kajdic, Primoz; Manchester, Ward B.; Lugaz, Noé
Bibcode: 2014JGRA..119...26L
Altcode:
  flux erosion by magnetic reconnection occurs at the front of at least
  some magnetic clouds (MCs). We first investigate how erosion influences
  the geo-effectiveness of MCs in a general sense and using a south-north
  magnetic polarity MC observed on 18-20 October 1995. Although the
  magnetic shear at its front may not be known during propagation,
  measurements at 1 AU show signatures of local reconnection. Using a
  standard MC model, an empirical model of the geomagnetic response (Dst),
  and an observational estimate of the magnetic flux erosion, we find that
  the strength of the observed ensuing storm was ~30% lower than if no
  erosion had occurred. We then discuss the interplay between adiabatic
  compression and magnetic erosion at the front of MCs. We conclude that
  the most geo-effective configuration for a south-north polarity MC
  is to be preceded by a solar wind with southward IMF. This stems not
  only from the formation of a geo-effective sheath ahead of it but also
  from the adiabatic compression and reduced (or lack thereof) magnetic
  erosion which constructively conspire for the structure to be more
  geo-effective. Finally, assuming simple semiempirical and theoretical
  Alfvén speed profiles expected from expansion to 1 AU, we provide
  first-order estimates of the erosion process radial evolution. We
  find that the expected reconnection rates during propagation allow for
  significant erosion, on the order of those reported. Calculations also
  suggest that most of the erosion should occur in the inner heliosphere,
  and up to ~50% may yet occur beyond Mercury's orbit.

Title: Global ICME-Mars Interaction and Induced Atmospheric Loss
Authors: Fang, X.; Ma, Y.; Manchester, W.
Bibcode: 2013AGUFM.P21A1701F
Altcode:
  Without the shielding of a strong intrinsic magnetic field, the
  present-day Mars atmosphere is more vulnerable to external solar
  wind forcing than the Earth's atmosphere. Therefore interplanetary
  coronal mass ejections (ICMEs) are expected to drive disturbances in
  the Mars environment in a profoundly different way, which, however,
  is poorly understood due to the lack of coordinated solar wind and
  Mars observations. In this study, three sophisticated models work in
  concert to simulate the physical domain extending from the solar corona
  to near-Mars space for the 13 May 2005 ICME event. The Space Weather
  Modeling Framework (SWMF) will be used to investigate the interaction
  of the ICME with the ambient solar wind and monitor its propagation
  from the Sun to the planet. A 3-D MHD model for Mars will be applied
  to assess the planetary atmospheric/ionospheric responses during the
  ICME passage of Mars. In the Mars weak magnetic field environment, the
  ion kinetic effects are important and will be included through the use
  of a 3-D Monte Carlo pickup ion transport model. These physics-based
  modeling efforts enable us to provide a global and time series view
  of the Mars response to transient solar wind disturbances and induced
  atmospheric loss, which is currently not possible due to the limitation
  of observations.

Title: The Interaction of Two Coronal Mass Ejections: Influence of
    Relative Orientation
Authors: Lugaz, N.; Farrugia, C. J.; Manchester, W. B., IV;
   Schwadron, N.
Bibcode: 2013ApJ...778...20L
Altcode: 2013arXiv1309.2210L
  We report on a numerical investigation of two coronal mass ejections
  (CMEs) that interact as they propagate in the inner heliosphere. We
  focus on the effect of the orientation of the CMEs relative to each
  other by performing four different simulations with the axis of
  the second CME rotated by 90° from one simulation to the next. Each
  magnetohydrodynamic simulation is performed in three dimensions with the
  Space Weather Modeling Framework in an idealized setting reminiscent of
  solar minimum conditions. We extract synthetic satellite measurements
  during and after the interaction and compare the different cases. We
  also analyze the kinematics of the two CMEs, including the evolution
  of their widths and aspect ratios. We find that the first CME contracts
  radially as a result of the interaction in all cases, but the amount of
  subsequent radial expansion depends on the relative orientation of the
  two CMEs. Reconnection between the two ejecta and between the ejecta
  and the interplanetary magnetic field determines the type of structure
  resulting from the interaction. When a CME with a high inclination
  with respect to the ecliptic overtakes one with a low inclination,
  it is possible to create a compound event with a smooth rotation in
  the magnetic field vector over more than 180°. Due to reconnection,
  the second CME only appears as an extended "tail," and the event
  may be mistaken for a glancing encounter with an isolated CME. This
  configuration differs significantly from the one usually studied of
  a multiple-magnetic-cloud event, which we found to be associated with
  the interaction of two CMEs with the same orientation.

Title: Earth's collision with a solar filament on 21 January 2005:
    Overview
Authors: Kozyra, J. U.; Manchester, W. B.; Escoubet, C. P.; Lepri,
   S. T.; Liemohn, M. W.; Gonzalez, W. D.; Thomsen, M. W.; Tsurutani,
   B. T.
Bibcode: 2013JGRA..118.5967K
Altcode:
  21 January 2005, one of the fastest interplanetary coronal mass
  ejections (ICME) of solar cycle 23, containing exceptionally dense
  plasma directly behind the sheath, hit the magnetosphere. We show from
  charge-state analysis that this material was a piece of the erupting
  solar filament and further, based on comparisons to the simulation
  of a fast CME, that the unusual location of the filament material
  was a consequence of three processes. As the ICME decelerated, the
  momentum of the dense filament material caused it to push through the
  flux rope toward the nose. Diverging nonradial flows in front of the
  filament moved magnetic flux to the sides of the ICME. At the same
  time, reconnection between the leading edge of the ICME and the sheath
  magnetic fields worked to peel away the outer layers of the flux rope
  creating a remnant flux rope and a trailing region of newly opened
  magnetic field lines. These processes combined to move the filament
  material into direct contact with the ICME sheath region. Within 1 h
  after impact and under northward interplanetary magnetic field (IMF)
  conditions, a cold dense plasma sheet formed within the magnetosphere
  from the filament material. Dense plasma sheet material continued to
  move through the magnetosphere for more than 6 h as the filament passed
  by the Earth. Densities were high enough to produce strong diamagnetic
  stretching of the magnetotail despite the northward IMF conditions and
  low levels of magnetic activity. The disruptions from the filament
  collision are linked to an array of unusual features throughout
  the magnetosphere, ionosphere, and atmosphere. These results raise
  questions about whether rare collisions with solar filaments may, under
  the right conditions, be a factor in producing even more extreme events.

Title: Evolution of the Global Temperature Structure of the Solar
    Corona during the Minimum between Solar Cycles 23 and 24
Authors: Nuevo, Federico A.; Huang, Zhenguang; Frazin, Richard;
   Manchester, Ward B., iv; Jin, Meng; Vásquez, Alberto M.
Bibcode: 2013ApJ...773....9N
Altcode:
  The combination of differential emission measure tomography with
  extrapolation of the photospheric magnetic field allows determination
  of the electron density and electron temperature along individual
  magnetic field lines. This is especially useful in quiet-Sun (QS)
  plasmas where individual loops cannot otherwise be identified. In Paper
  I, this approach was applied to study QS plasmas during Carrington
  rotation (CR) 2077 at the minimum between solar cycles (SCs) 23 and
  24. In that work, two types of QS coronal loops were identified: "up"
  loops in which the temperature increases with height, and "down" loops
  in which the temperature decreases with height. While the first ones
  were expected, the latter ones were a surprise and, furthermore, were
  found to be ubiquitous in the low-latitude corona. In the present work,
  we extend the analysis to 11 CRs around the last solar minimum. We
  found that the "down" population, always located at low latitudes,
  was maximum at the time when the sunspot number was minimum, and the
  number of down loops systematically increased during the declining
  phase of SC-23 and diminished during the rising phase of SC-24. "Down"
  loops are found to have systematically larger values of β than do
  "up" loops. These discoveries are interpreted in terms of excitation
  of Alfvén waves in the photosphere, and mode conversion and damping
  in the low corona.

Title: Numerical Simulations of Coronal Mass Ejection on 2011 March 7:
    One-temperature and Two-temperature Model Comparison
Authors: Jin, M.; Manchester, W. B.; van der Holst, B.; Oran, R.;
   Sokolov, I.; Toth, G.; Liu, Y.; Sun, X. D.; Gombosi, T. I.
Bibcode: 2013ApJ...773...50J
Altcode:
  During Carrington rotation (CR) 2107, a fast coronal mass ejection (CME;
  &gt;2000 km s<SUP>-1</SUP>) occurred in active region NOAA 11164. This
  event is also associated with a solar energetic particle event. In
  this study, we present simulations of this CME with one-temperature
  (1T) and two-temperature (2T: coupled thermodynamics of the electron
  and proton populations) models. Both the 1T and 2T models start from
  the chromosphere with heat conduction and radiative cooling. The
  background solar wind is driven by Alfvén-wave pressure and heated
  by Alfvén-wave dissipation in which we have incorporated the balanced
  turbulence at the top of the closed field lines. The magnetic field of
  the inner boundary is set up using a synoptic map from Solar Dynamics
  Observatory/Helioseismic and Magnetic Imager. The Titov-Démoulin
  flux-rope model is used to initiate the CME event. We compare the
  propagation of fast CMEs and the thermodynamics of CME-driven shocks in
  both the 1T and 2T CME simulations. Also, the synthesized white light
  images are compared with the Solar and Heliospheric Observatory/Large
  Angle and Spectrometric Coronagraph observations. Because there is no
  distinction between electron and proton temperatures, heat conduction
  in the 1T model creates an unphysical temperature precursor in front
  of the CME-driven shock and makes the shock parameters (e.g., shock
  Mach number, compression ratio) incorrect. Our results demonstrate
  the importance of the electron heat conduction in conjunction with
  proton shock heating in order to produce the physically correct CME
  structures and CME-driven shocks.

Title: Turbulence Model for Multi-Band EUV Emission in the Solar
    Atmosphere
Authors: van der Holst, Bart; Sokolov, I.; Manchester, W.; Jin, M.;
   Oran, R.; Gombosi, T.
Bibcode: 2013shin.confE.104V
Altcode:
  The low corona is the heart of global solar models, because that is
  where the interplanetary magnetic fields, solar wind, coronal heating,
  and solar flares originate. Multi-wavelength observations obtained by
  SDO/AIA and STEREO/EUVI provide very important detailed information
  on the morphology, thermodynamic status and evolution of the low
  solar corona. Observations from SDO and STEREO can thus be used to
  effectively constrain and validate numerical models of the lower solar
  atmosphere. <P />We present a global model of the lower solar corona
  in which the coronal heating and solar wind acceleration are addressed
  with low-frequency, reflection-driven Alfven wave turbulence. At the
  inner boundary the Poynting flux of the Alfven waves is prescribed to
  be proportional to the magnetic field strength. A unique key feature
  of this model is that the wave dissipation on open and closed field
  lines is incorporated in a unified manner. The model does not impose
  open-closed magnetic field boundaries, those naturally develop from
  the ingested observed photospheric magnetic fields and the used wave
  dissipation mechanism. On open field lines the turbulence is strongly
  imbalanced, so that the turbulent cascade due to the linear wave
  reflection is proportional to the Alfven speed gradients. However,
  near the top of closed field the turbulence is balanced, resulting
  in enhanced nonlinear dissipation. The simulated multi-wavelength EUV
  images are compared with the observations from SDO/AIA and STEREO/EUVI
  instruments to test this turbulence model.

Title: Global Modeling of the July 23, 2012 Coronal Mass Ejection
    and Solar Energetic Particle Event
Authors: Evans, Rebekah Minnel; Kozarev, Kamen A.; Schwadron, Nathan
   A.; Opher, Merav; Manchester, Ward; Sokolov, Igor; van der Holst, Bart
Bibcode: 2013shin.confE...7E
Altcode:
  The CME and SEP event of July 23, 2012 was extreme in many ways - the
  speed of a CME as imaged in coronagraphs, the speed and magnetic field
  strength measured in-situ, and the level of energetic particles. Another
  special feature of this event is that it caused SEP events at Earth,
  STEREO A and STEREO B, which were very separated at the time. The
  extreme and whole-heliosphere nature of this event makes it an
  excellent candidate to study with two recently coupled models: the
  Space Weather Modeling Framework (SWMF) and the Energetic Particle
  Radiation Environment Module (EPREM). The SWMF, which itself couples
  three-dimensional magnetohydrodynamic (MHD) models describing the solar
  corona and heliosphere, is used to simulate the eruption starting
  from the low corona. The MHD output describing the fast CME event
  is coupled to a global kinetic simulation of particle acceleration
  and transport within EPREM. The output of the particle simulation is
  synthetic time-dependent spectra influenced by the dynamics of CME
  structures that form self-consistently during propagation. With these
  simulations, we can probe how the properties of the CME sheath and shock
  vary as the CME interacts with the ambient corona and heliosphere. These
  simulations can test current theories of SEP production, including
  how SEP properties relate to the properties of the associated CME,
  CME-driven shock and coronal environment. Finally, we can trace how
  particles that interacted with the CME near the Sun propagate throughout
  the heliosphere.

Title: CME-CME Interaction: Influence of Relative Orientation
Authors: Lugaz, Noe; Farrugia, C. J.; Manchester, W. B.; Schwadron, N.
Bibcode: 2013shin.confE.146L
Altcode:
  We report on an numerical investigation of the interaction of two
  coronal mass ejections (CMEs) as they propagate between the Sun and the
  Earth. We focus on the effect of the relative orientation of the CMEs
  with respect to each other by performing four different simulations with
  the axis of the second CME rotated by 90 degrees from one simulation to
  the next. The simulations are performed with the SWMF in an idealized
  setting reminiscent of solar minimum conditions. We have extracted
  synthetic satellite measurements in the inner heliosphere at 0.15, 0.3,
  and 1 AU and have compared the different cases. We find significant
  differences in the reconnection between the different ejecta and with
  the interplanetary magnetic field (IMF). In particular, when a CME with
  a high inclination with respect to the ecliptic overtakes one with a
  low inclination, it is possible to create a compound event with smooth
  rotations in the magnetic field vector and an extended tail, which may
  be mistaken for an usual crossing of a single, isolated CME. We also
  analyze the kinematics of the two CMEs in different cases, including
  their expansion rate, and we discuss their expected geo-effectiveness.

Title: Stability of Inverted Temperature Loops in the Quiet Corona
Authors: Huang, Zhenguang; Frazin, Richard A.; van der Holst, Bart;
   Nuevo, Federico A.; Vasquez, Alberto M.; Manchester, Ward B., IV;
   Sokolov, Igor V.; Gombosi, Tamas I.
Bibcode: 2013shin.confE..85H
Altcode:
  Recent investigations of the quiet Corona have revealed the existence
  of inverted temperature

