Mirror instability driven by pickup ions in the outer heliosheath
- 1Southern University of Science and Technology, Department of Earth and Space Sciences, Shenzhen, China (mousavi@sustech.edu.cn)
- 2Department of Astronomy and Space Science, Chungnam National University, Daejeon, South Korea
Kinetic linear instability analysis and hybrid simulations are carried out to examine the role of mirror instability in scattering the pickup ions in the outer heliosheath. The dynamics of these pickup ions is essential to
the understanding of the energetic neutral atom (ENA) ribbon observed by the Interstellar Boundary EXplorer
(IBEX). While most previous studies have focused on the ion cyclotron instability driven by the pickup ions,
recent work based on a simple ring velocity distribution of the pickup ions suggested that the mirror mode can
also be unstable and contribute to the scattering of the pickup ions. The present study performs linear analysis
as well as hybrid simulations for a more realistic, multi-component pickup ion velocity distribution given by the
global modeling of neutral atoms in the heliosphere. The linear theory results indicate unstable mirror modes
with considerable growth rates. The corresponding hybrid simulations further confirm that the mirror modes can
grow and aid the pitch-angle broadening of the pickup ions. So the role of mirror mode should not be ignored in
the stability study of the outer heliosheath pickup ions.
How to cite: Mousavianzehaie, A., Liu, K., and Min, K.: Mirror instability driven by pickup ions in the outer heliosheath, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-2107, https://doi.org/10.5194/egusphere-egu2020-2107, 2020.
