The velocity particle distributions measured in-situ in space plasmas deviate from Maxwellian (thermal) equilibrium, showing enhanced suprathermal tails which are well described by the standard Kappa-distribution (SKD). Despite its successful application, the SKD is frequently disputed due to a series of unphysical implications like diverging velocity moments, preventing a macroscopic description of the plasma. The regularized Kappa-distribution (RKD) has been introduced to overcome these limitations, but the dispersion properties of RKD-plasmas are not explored yet. In the present paper we compute the wavenumber dispersion of the frequency and damping or growth rates for the electromagnetic modes in plasmas characterized by the RKD. This task is accomplished by using the grid-based kinetic dispersion solver LEOPARD developed for arbitrary gyrotropic distributions [P. Astfalk and F. Jenko, J. Geophys. Res. 122, 89 (2017)]. By reproducing previous results obtained for the SKD and Maxwellian, we validate the functionality of the code. Furthermore, we apply the isotropic as well as the anisotropic RKDs to investigate stable electromagnetic electron-cyclotron (EMEC) and ion-cyclotron (EMIC) modes as well as temperature-anisotropy-driven instabilities, both for the case $T_\perp / T_\parallel > 1$ (EMEC and EMIC instabilities) and for the case $T_\perp / T_\parallel < 1$ (proton and electron firehose instabilities), where $\parallel$ and $\perp$ denote directions parallel and perpendicular to the local time-averaged magnetic field. Provided that the cutoff parameter $α$ is small enough, the results show that the RKDs reproduce the dispersion curves of the SKD plasmas at both qualitative and quantitative levels. For higher values, however, physically significant deviation occurs.
Loading non-Maxwellian Velocity Distributions in Particle Simulations
Space Research Institute, Austrian Academy of Sciences（奥地利科学院空间研究所）；National Institute for Fusion Science（国立研究开发法人核聚变科学研究所）；Faculty of Engineering Sciences, Kyushu University（九州大学工学研究院）
Kinetic-based macro-modeling of the solar wind at large heliocentric distances: Kappa electrons at the exobase
KU Leuven（荷语鲁汶大学）；European Space Agency (ESA), European Space Astronomy Centre (ESAC)（欧洲航天局（ESA）欧洲航天天文中心（ESAC））；Ruhr-University Bochum（波鸿鲁尔大学）；Royal Belgian Institute for Space Aeronomy (BIRA-IASB)（比利时皇家空间气动力学研究所（BIRA-IASB））；Université Catholique de Louvain（天主教鲁汶大学）；University of Maria Curie-Skłodowska（玛丽亚·居里-斯可罗多夫斯卡大学）
Modeling complex plasma instabilities in space plasmas - Three-component electron formalism of heat-flux instabilities
Ruhr-Universität Bochum（波鸿鲁尔大学）；KU Leuven（荷语鲁汶大学）；Comisión Chilena de Energía Nuclear（智利核能委员会）；Universidad Andres Bello（安德烈斯贝略大学）；University of Maria Curie-Skłodowska（玛丽亚·居里-斯克沃多夫斯卡大学）
