Simulation of radiation belt wave-particle interactions in an MHD-particle framework

Frontiers in Astronomy and Space Sciences

Astronomy and Space Sciences

Jay M. Albert¹  Qianli Ma²  Wen Li²  Shah S. Alam³  Anthony A. Chan³  Suhail A. Aldhurais⁴  William J. Longley⁵  Allison N. Jaynes⁶  Scot R. Elkington⁷  David M. Malaspina⁸ 

[1] Air Force Research Laboratory, Kirtland AFB, NM, United States;Center for Space Physics, Boston University, Boston, MA, United States;Department of Physics and Astronomy, Rice University, Houston, TX, United States;Department of Physics and Astronomy, Rice University, Houston, TX, United States;Applied Physics Graduate Program, Smalley-Curl Institute, Rice University, Houston, TX, United States;Physics Department, King Fahd University of Petroleum and Minerals, Dhahran, Saudi Arabia;Department of Physics and Astronomy, Rice University, Houston, TX, United States;Center for Solar-Terrestrial Research, New Jersey Institute of Technology, Newark, NJ, United States;Department of Physics and Astronomy, University of Iowa, Iowa, IA, United States;Laboratory for Atmospheric and Space Physics, University of Colorado, Boulder, CO, United States;Laboratory for Atmospheric and Space Physics, University of Colorado, Boulder, CO, United States;Astrophysical and Planetary Sciences Department, University of Colorado, Boulder, CO, United States;

关键词: radiation belts of magnetized planets;    wave-particle interaction;    energetic particles;    magnetospheric plasma waves;    quasilinear and non-linear theory;    numerical simulation;   

DOI  :  10.3389/fspas.2023.1239160

 received in 2023-06-12, accepted in 2023-08-21,  发布年份 2023

来源: Frontiers

【 摘 要 】

In this paper we describe K2, a comprehensive simulation model of Earth’s radiation belts that includes a wide range of relevant physical processes. Global MHD simulations are combined with guiding-center test-particle methods to model interactions with ultra low-frequency (ULF) waves, substorm injections, convective transport, drift-shell splitting, drift-orbit bifurcations, and magnetopause shadowing, all in self-consistent MHD fields. Simulation of local acceleration and pitch-angle scattering due to cyclotron-scale interactions is incorporated by including stochastic differential equation (SDE) methods in the MHD-particle framework. The SDEs are driven by event-specific bounce-averaged energy and pitch-angle diffusion coefficients. We present simulations of electron phase-space densities during a simplified particle acceleration event based on the 17 March 2013 event observed by the Van Allen Probes, with a focus on demonstrating the capabilities of the K2 model. The relative wave-particle effects of global scale ULF waves and very-low frequency (VLF) whistler-mode chorus waves are compared, and we show that the primary acceleration appears to be from the latter. We also show that the enhancement with both ULF and VLF processes included exceeds that of VLF waves alone, indicating a synergistic combination of energization and transport processes may be important.

【 授权许可】

Unknown   
Copyright © 2023 Chan, Elkington, Longley, Aldhurais, Alam, Albert, Jaynes, Malaspina, Ma and Li.