Scalings for the Alfvén-cyclotron instability in a bi-kappa plasma

作     者：YueQun Lou Xing Cao MingYu Wu BinBin Ni TieLong Zhang YueQun Lou;Xing Cao;MingYu Wu;BinBin Ni;TieLong Zhang

作者机构：Shenzhen Key Laboratory of Numerical Prediction for Space StormInstitute of Space Science and Applied TechnologyHarbin Institute of TechnologyShenzhen 518055China Key Laboratory of Solar Activity and Space WeatherNational Space Science CenterChinese Academy of SciencesBeijing 100190China Department of Space PhysicsSchool of Electronic InformationWuhan UniversityWuhan 430072China Chinese Academy of Sciences Center for Excellence in Comparative PlanetologyHefei 230026China Space Research InstituteAustrian Academy of SciencesGraz 8042Austria 

出 版 物：《Earth and Planetary Physics》 (地球与行星物理（英文版）)

年 卷 期：2023年第7卷第6期

页      面：631-639页

核心收录：

学科分类：070802[理学-空间物理学] 07[理学] 0708[理学-地球物理学] 

基　　金：This work was supported by the National Natural Science Foundation of China(Grant Nos.42204163,42188101,42025404,42241143,41774167,41774171,41974205,41804157,41904156,42130204,and 42241133) the B-type Strategic Priority Program of the Chinese Academy of Sciences(Grant No.XDB41000000) the National Key R&D Program of China(Grant Nos.2022YFF0503700 and 2022YFF0503900) the pre-research projects on Civil Aerospace Technologies(Grant No.D020103)funded by the China National Space Administration the Macao Foundation,the Fundamental Research Funds for the Central Universities(Grant No.2042022kf1012 the Shenzhen Key Laboratory Launching Project(Grant No.ZDSYS20210702140800001).TieLong Zhang was supported by the Chinese Academy of Sciences Center for Excellence in Comparative Planetology 

主　　题：Alfvén-cyclotron instability kappa distribution kinetic linear dispersion theory scaling formula 

摘      要：The particle velocity distribution in space plasma usually exhibits a non-Maxwellian high-energy tail that can be well modeled by kappa *** this study,we focus on the growth rates of the Alfvén-cyclotron instability driven by ion temperature anisotropy in a kappa *** solving the kinetic linear dispersion equation,we explore the sensitivity of growth rates to the spectral indexκof a bi-kappa distribution under different plasma conditions,including a variety of plasma beta β_(hp) and temperature anisotropy A_(hp) values of hot ***,a concise,analytic scaling formula is derived that relates the dimensionless maximum growth rate to three independent variables:the spectral index and the plasma beta and temperature anisotropy of hot *** results show that as theκ-value increases,the instability bandwidth narrows and the maximum growth rate increases *** higherβ_(hp)and A_(hp)′the maximum instability undergoes a sharp increase as *** our fits of dimensionless maximum growth rates are compared with solutions to kinetic linear dispersion theory,the results generally exhibit good agreement between *** under the circumstances of largeκ-values and highβ_(hp)and A_(hp)′the scalings of maximum growth rates primarily accurately model the numerical *** analytic expressions can readily be used in large-scale models of the Earth’s magnetosphere to understand wave generation due to the Alfvén-cyclotron instability.