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Title: Bi-Kappa Proton Mirror and Cyclotron Instabilities in the Solar Wind
The charged particles in the solar wind are often observed to possess a nonthermal tail in the velocity distribution function, a feature that can be fitted with the Kappa model. The anisotropic, or bi-Kappa, model of protons, electrons, and other charged particles is thus adopted in the literature for interpreting the data as well as in the context of the analysis of wave–particle interactions. The present paper develops an approximate but efficient theory of the mirror and cyclotron instabilities excited by the bi-Kappa protons in the solar wind. A velocity moment-based quasi-linear theory of these instabilities is also formulated in order to investigate the saturation behavior. Applications of the formalism are made for instabilities close to the marginally unstable state, which is typical of the solar wind near 1 au.  more » « less
Award ID(s):
2203321
PAR ID:
10494267
Author(s) / Creator(s):
; ;
Publisher / Repository:
IOP Publishing, AAS
Date Published:
Journal Name:
The Astrophysical Journal
Volume:
950
Issue:
2
ISSN:
0004-637X
Page Range / eLocation ID:
131
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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