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Astronomy & Astrophysics
N. A. Schwadron, C. J. Joyce, A. Aly, C. M. S. Cohen, M. Desai, D. J. McComas, J. T. Niehof, E. Mobius, M. Lee, J. Bower, S. Bale, A. Case, E. R. Christian, A. J. Davis, W. de Wet, K. Goetz, J. Giacalone, M. E. Hill, R. Allen, J. C. Kasper, K. Korreck, R. A. Leske, O. Malandraki, W. H. Matthaeus, R. L. McNutt, R. A. Mewaldt, D. G. Mitchell, M. Pulupa, J. S. Rankin, E. C. Roelof, E. C. Stone, J. R. Szalay, M. E. Wiedenbeck
Summary: Early observations from PSP's first orbit reveal recurrent stream interaction regions near the Sun and the presence of energetic particle enhancements. The long duration of energetic particle enhancements suggests direct streaming of particles along magnetic field lines forming a sub-Parker spiral structure.
ASTRONOMY & ASTROPHYSICS
(2021)
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Astronomy & Astrophysics
Allan R. Macneil, Mathew J. Owens, Adam J. Finley, Sean P. Matt
Summary: The study evaluates the heliospheric portion of two-step backmapping, finding that mapping using models can achieve good average agreement with observed data, but with significant standard deviation. It also suggests that previous assumptions about interplanetary acceleration and solar wind corotation height may have been overestimated, and that error cancellation may contribute to the performance of ballistic mapping.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2022)
Article
Astronomy & Astrophysics
Athanasios Papaioannou, Konstantin Herbst, Tobias Ramm, Edward W. Cliver, David Lario, Astrid M. Veronig
Summary: The potential impact of solar superflares on the radiation environment around Earth is assessed by studying the relationship between the peak proton flux and fluence of solar energetic particle (SEP) events and the solar flare soft X-ray peak photon flux.
ASTRONOMY & ASTROPHYSICS
(2023)
Article
Astronomy & Astrophysics
A. Aran, D. Pacheco, M. Laurenza, N. Wijsen, D. Lario, S. Benella, I. G. Richardson, E. Samara, J. L. Freiherr von Forstner, B. Sanahuja, L. Rodriguez, L. Balmaceda, F. Espinosa Lara, R. Gomez-Herrero, K. Steinvall, A. Vecchio, V Krupar, S. Poedts, R. C. Allen, G. B. Andrews, V Angelini, L. Berger, D. Berghmans, S. Boden, S. Bottcher, F. Carcaboso, I Cernuda, R. De Marco, S. Eldrum, V Evans, A. Fedorov, J. Hayes, G. C. Ho, T. S. Horbury, N. P. Janitzek, Yu Khotyaintsev, A. Kollhoff, P. Kuehl, S. R. Kulkarni, W. J. Lees, P. Louarn, J. Magdalenic, M. Maksimovic, O. Malandraki, A. Martinez, G. M. Mason, C. Martin, H. O'Brien, C. Owen, P. Parra, M. Prieto Mateo, A. Ravanbakhsh, J. Rodriguez-Pacheco, O. Rodriguez Polo, S. Sanchez Prieto, C. E. Schlemm, H. Seifert, J. C. Terasa, K. Tyagi, C. Verbeeck, R. F. Wimmer-Schweingruber, Z. G. Xu, M. K. Yedla, A. N. Zhukov
Summary: This study presents in situ particle measurements of the first proton event observed by the Energetic Particle Detector suite on the Solar Orbiter mission. The findings suggest that the observed galactic cosmic ray decrease was due to a solar wind stream interaction region. Additionally, the study highlights the recurrent nature of this interaction and the possible complexities of the interplanetary structure.
ASTRONOMY & ASTROPHYSICS
(2021)
Article
Astronomy & Astrophysics
M. Liu, K. Issautier, N. Meyer-Vernet, M. Moncuquet, M. Maksimovic, J. S. Halekas, J. Huang, L. Griton, S. Bale, J. W. Bonnell, A. W. Case, K. Goetz, P. R. Harvey, J. C. Kasper, R. J. MacDowall, D. M. Malaspina, M. Pulupa, M. L. Stevens
Summary: The study investigates the solar wind energy flux in the inner heliosphere using data from Parker Solar Probe observations. The results show that the energy flux values are similar to those derived from observations by various satellites over a 24-year period.
ASTRONOMY & ASTROPHYSICS
(2021)
Article
Astronomy & Astrophysics
N. Dresing, L. Rodriguez-Garcia, I. C. Jebaraj, A. Warmuth, S. Wallace, L. Balmaceda, T. Podladchikova, R. D. Strauss, A. Kouloumvakos, C. Palmroos, V. Krupar, J. Gieseler, Z. Xu, J. G. Mitchell, C. M. S. Cohen, G. A. de Nolfo, E. Palmerio, F. Carcaboso, E. K. J. Kilpua, D. Trotta, U. Auster, E. Asvestari, D. da Silva, W. Droge, T. Getachew, R. Gomez-Herrero, M. Grande, D. Heyner, M. Holmstroem, J. Huovelin, Y. Kartavykh, M. Laurenza, C. O. Lee, G. Mason, M. Maksimovic, J. Mieth, G. Murakami, P. Oleynik, M. Pinto, M. Pulupa, I. Richter, J. Rodriguez-Pacheco, B. Sanchez-Cano, F. Schuller, H. Ueno, R. Vainio, A. Vecchio, A. M. Veronig, N. Wijsen
Summary: On April 17, 2021, a complex and long-lasting solar eruption produced a widespread solar energetic particle event that was observed by five well-separated observers in the inner heliosphere. The event was the second of its kind in solar cycle 25 and produced relativistic electrons and protons. The aim of this study was to understand the reasons for the wide spread of elevated SEP intensities and identify the source regions of the observed particles.
ASTRONOMY & ASTROPHYSICS
(2023)
Article
Astronomy & Astrophysics
Pedro Osuna Alcalaya, Ioannis Zouganelis, Javier Rodriguez Pacheco
Summary: A new model is proposed for kinetic collisionless modeling of the solar wind, which does not separate populations into different trajectories for integrals calculation. This model provides an analytic solution for the electrostatic potential of the solar wind valid for all distances. The results show a non-monotonic total potential, similar to other models, indicating the importance of electron distribution functions in shaping the electrostatic potential of thermal solar-like outflows.
ASTRONOMY & ASTROPHYSICS
(2021)
Article
Astronomy & Astrophysics
J. M. Schroeder, S. Boldyrev, P. Astfalk
Summary: This study presents a kinetic stability analysis of the solar wind electron distribution, revealing instabilities in the core-strahl electron distribution at specific heliospheric distances induced by various modes. These instabilities are primarily driven by the relative drift between electron and ion cores.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2021)
Article
Astronomy & Astrophysics
R. Laker, T. S. Horbury, L. Matteini, S. D. Bale, J. E. Stawarz, L. D. Woodham, T. Woolley
Summary: Switchbacks are magnetic fluctuations in the solar wind that exhibit large rotations. This study re-examines the deflection direction of switchbacks and finds a systematic deflection direction consistent with interchange reconnection.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2022)
Article
Astronomy & Astrophysics
S. D. Korolkov, V. V. Izmodenov
Summary: The study aims to demonstrate that shock-wave heating is sufficient to explain the nonadiabatic radial profile of the solar wind proton temperature. By using a high-resolution data-driven solar wind model, the numerical simulations show good agreement with the observations obtained by Voyager-2.
ASTRONOMY & ASTROPHYSICS
(2022)
Article
Astronomy & Astrophysics
N. Wijsen, A. Aran, C. Scolini, D. Lario, A. Afanasiev, R. Vainio, B. Sanahuja, J. Pomoell, S. Poedts
Summary: We simulated the ESP event on 14 July 2012 using the PARADISE and EUHFORIA models. The results show both the capabilities and limitations of the models. The simulations and observations diverge in some aspects, and we discuss the sources of errors and potential mitigation strategies.
ASTRONOMY & ASTROPHYSICS
(2022)
Article
Astronomy & Astrophysics
Allan R. Macneil, Mathew J. Owens, Robert T. Wicks, Mike Lockwood
Summary: Research shows that HMF inversions observed by the Parker Solar Probe are typically characterized by anticorrelated field and velocity perturbations, exhibiting Alfvenic properties. As the distance from the Sun increases, these inversions depart further from the 'ideal' Alfvenic case.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2021)
Article
Astronomy & Astrophysics
R. F. Wimmer-Schweingruber, N. P. Janitzek, D. Pacheco, I Cernuda, F. Espinosa Lara, R. Gomez-Herrero, G. M. Mason, R. C. Allen, Z. G. Xu, F. Carcaboso, A. Kollhoff, P. Kuehl, J. L. Freiherr von Forstner, L. Berger, J. Rodriguez-Pacheco, G. C. Ho, G. B. Andrews, V Angelini, A. Aran, S. Boden, S. Bottcher, A. Carrasco, N. Dresing, S. Eldrum, R. Elftmann, V Evans, O. Gevin, J. Hayes, B. Heber, T. S. Horbury, S. R. Kulkarni, D. Lario, W. J. Lees, O. Limousin, O. E. Malandraki, C. Martin, H. O'Brien, M. Prieto Mateo, A. Ravanbakhsh, O. Rodriguez-Polo, S. Sanchez Prieto, C. E. Schlemm, H. Seifert, J. C. Terasa, K. Tyagi, R. Vainio, A. Walsh, M. K. Yedla
Summary: During its first year of operations, Solar Orbiter's Energetic Particle Detector (EPD) has collected data on multiple particle events at distances ranging from 0.5 to 1 au from the Sun, showcasing the energy spectra of ions and electrons, as well as analyzing and illustrating the enrichment of heavy ions and electron anisotropy in certain events.
ASTRONOMY & ASTROPHYSICS
(2021)
Article
Astronomy & Astrophysics
L. Rodriguez-Garcia, R. Gomez-Herrero, I Zouganelis, L. Balmaceda, T. Nieves-Chinchilla, N. Dresing, M. Dumbovic, N. Nitta, F. Carcaboso, L. F. G. dos Santos, L. K. Jian, L. Mays, D. Williams, J. Rodriguez-Pacheco
Summary: The study aims to explain the reasons for the different intensity-time profiles observed by spacecraft and to identify the solar source related to the widespread SEP event. Analysis of in situ data and remote-sensing observations suggests that a shock driven by the CME is the solar source of the SEP event, while differences in intensity-time profiles can be attributed to particle scattering beyond Mercury's orbit.
ASTRONOMY & ASTROPHYSICS
(2021)
Article
Astronomy & Astrophysics
R. Laker, T. S. Horbury, S. D. Bale, L. Matteini, T. Woolley, L. D. Woodham, S. T. Badman, M. Pulupa, J. C. Kasper, M. Stevens, A. W. Case, K. E. Korreck
Summary: Researchers investigated the characteristics of magnetic switchbacks in different solar wind streams and found that they are typically aligned along the local Parker spiral rather than the background flow direction. The switchbacks had a mean width of 50,000 km and an aspect ratio of about 10.
ASTRONOMY & ASTROPHYSICS
(2021)