[P-EM25] 太陽圏・惑星間空間

[PEM25-01] 高ベータ低マッハ数衝撃波のおける電子加速

*松清 修一¹、松本 洋介² (1.九州大学、2.千葉大学)

キーワード：無衝突衝撃波, 数値実験, 粒子加速

Voyager spacecraft revealed that the solar wind termination shock is a rather weak shock since the upstream plasma beta is high and effective Mach number of the shock is low due to the presence of pickup ions. Nevertheless, the fluxes of non-thermal electrons and ions (the latter are called as termination shock particles) are enhanced when crossing the termination shock. Electron acceleration at a weak shock is also reported in terms of galaxy cluster merger shocks. In this study we perform two-dimensional full particle-in-cell simulation to discuss microstructure of the high beta and low Mach number shock and the associated electron acceleration. Unlike a one-dimensional simulation, electrons are not reflected at the shock when a shock angle is close to 90 deg. due to the effect of rippling. Nevertheless, some electrons are accelerated locally at the transition region. Wave-particle interactions appear to play a role.