Observations of the Source Region of Whistler Mode Waves in Magnetosheath Mirror Structures
| العنوان: | Observations of the Source Region of Whistler Mode Waves in Magnetosheath Mirror Structures |
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| المؤلفون: | Per-Arne Lindqvist, Barbara L. Giles, Scott A. Boardsen, W. R. Paterson, D. J. Gershman, Christopher T. Russell, C. J. Pollock, Shoichiro Yokota, Yoshiharu Omura, N. Kitamura, Takanobu Amano, Robert E. Ergun, James L. Burch, Robert J. Strangeway, O. Le Contel, Narges Ahmadi, Shota Nakamura, Yoshitaka Saito |
| المساهمون: | Radio Science Center for Space and Atmosphere [Kyoto] (RASC), Kyoto University [Kyoto], GSFC Cryospheric Sciences Laboratory, NASA Goddard Space Flight Center (GSFC), Laboratoire de Physique des Plasmas (LPP), Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-École polytechnique (X)-Sorbonne Université (SU)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), Laboratory for Atmospheric and Space Physics [Boulder] (LASP), University of Colorado [Boulder], Institute of Space and Astronautical Science (ISAS), Japan Aerospace Exploration Agency [Sagamihara] (JAXA), Denali Scientific, NASA Headquarters, Department of Earth, Planetary and Space Sciences [Los Angeles] (EPSS), University of California [Los Angeles] (UCLA), University of California-University of California, Institute of Geophysics and Planetary Physics [Los Angeles] (IGPP), Space Science Division [San Antonio], Southwest Research Institute [San Antonio] (SwRI) |
| المصدر: | Journal of Geophysical Research Space Physics Journal of Geophysical Research Space Physics, American Geophysical Union/Wiley, 2020, 125 (5), ⟨10.1029/2019JA027488⟩ |
| بيانات النشر: | HAL CCSD, 2020. |
| سنة النشر: | 2020 |
| مصطلحات موضوعية: | Physics, 010504 meteorology & atmospheric sciences, [PHYS.ASTR.EP]Physics [physics]/Astrophysics [astro-ph]/Earth and Planetary Astrophysics [astro-ph.EP], Mode (statistics), whistler mode waves, mirror mode structures, 01 natural sciences, Computational physics, Magnetic field, Geophysics, Magnetosheath, Space and Planetary Science, wave generation, Physics::Space Physics, MMS spacecraft, Whistler mode, 0105 earth and related environmental sciences |
| الوصف: | International audience; In the magnetosheath, intense whistler mode waves, called “Lion roars,” are often detected in troughs of magnetic field intensity in mirror mode structures. Using data obtained by the four Magnetospheric Multiscale (MMS) spacecraft, we show that reversals of gradient of magnetic field intensity along the magnetic field correspond to reversals of the field‐aligned component of Poynting flux of whistler mode waves in the troughs. Such a characteristic is consistent with the idea that the whistler mode waves are effectively generated near the local minima of magnetic field intensity because of the smallest cyclotron resonance velocity and propagate toward regions of larger magnetic field intensity along the magnetic field lines on both sides. We use the reversal of the Poynting flux as an indicator of wave source regions. In these regions, we find that pancake or an outer edge of butterfly electron distributions above ~100 eV are good candidates for wave generation. Unclear correlations of phase difference and amplitude variations of whistler mode waves in cases of ~40 km spacecraft separation indicate that a simple plane wave approximation with a constant amplitude is not valid at this spatial scale that is much smaller than the ion gyroradius. The whistler mode waves consist of small coherent wave packets from multiple sources with spatial scales smaller than tens of electron gyroradii transverse to the background magnetic field in a mirror mode structure.Publication cover image |
| اللغة: | English |
| تدمد: | 2169-9380 2169-9402 |
| DOI: | 10.1029/2019JA027488⟩ |
| URL الوصول: | https://explore.openaire.eu/search/publication?articleId=doi_dedup___::d1cd2abb7a310a9e8da28977f595df4a https://hal.archives-ouvertes.fr/hal-02863627 |
| Rights: | CLOSED |
| رقم الانضمام: | edsair.doi.dedup.....d1cd2abb7a310a9e8da28977f595df4a |
| قاعدة البيانات: | OpenAIRE |
| تدمد: | 21699380 21699402 |
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| DOI: | 10.1029/2019JA027488⟩ |