Open AccessAlfvén waves in the magnetosphere generated by shock wave / plasmapause interaction
Author(s) -
A. S. Leonovich,
A. S. Leonovich,
Цюган Цзун,
Qiugang Zong,
Д. А. Козлов,
Д. А. Козлов,
Юнфу Ван,
Yongfu Wang
Publication year - 2019
Publication title -
solnečno-zemnaâ fizika
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.11
H-Index - 2
ISSN - 2412-4737
DOI - 10.12737/szf-52201902
Subject(s) - physics , magnetosphere , plasmasphere , polarization (electrochemistry) , shock wave , toroid , whistler , computational physics , oscillation (cell signaling) , field line , plasma , quantum electrodynamics , geophysics , mechanics , chemistry , quantum mechanics , biology , genetics
We study Alfvén waves generated in the magnetosphere during the passage of an interplanetary shock wave. After shock wave passage, the oscillations with typical Alfvén wave dispersion have been detected in spacecraft observations inside the magnetosphere. The most frequently observed oscillations are those with toroidal polarization; their spatial structure is described well by the field line resonance (FLR) theory. The oscillations with poloidal polarization are observed after shock wave passage as well. They cannot be generated by FLR and cannot result from instability of high-energy particle fluxes because no such fluxes were detected at that time. We discuss an alternative hypothesis suggesting that resonant Alfvén waves are excited by a secondary source: a highly localized pulse of fast magnetosonic waves, which is generated in the shock wave/plasmapause contact region. The spectrum of such a source contains oscillation harmonics capable of exciting both the toroidal and poloidal resonant Alfvén waves.