Impact of Shock Front Rippling and Self-reformation on the Electron Dynamics at Low-Mach-number Shocks

	Impact of Shock Front Rippling and Self-reformation on the Electron Dynamics at Low-Mach-number Shocks
	Yang, ZW ; Lu, QM ; Liu, YD ; Wang, R
刊名	ASTROPHYSICAL JOURNAL
	2018
卷号	857 期号:1 页码:36
关键词	Acceleration Of Particles Shock Waves Sun: Heliosphere
ISSN号	0004-637X
英文摘要	Electron dynamics at low-Mach-number collisionless shocks are investigated by using two-dimensional electromagnetic particle-in-cell simulations with various shock normal angles. We found: (1) The reflected ions and incident electrons at the shock front provide an effective mechanism for the quasi-electrostatic wave generation due to the charge-separation. A fraction of incident electrons can be effectively trapped and accelerated at the leading edge of the shock foot. (2) At quasi-perpendicular shocks, the electron trapping and reflection is non-uniform due to the shock rippling along the shock surface and is more likely to take place at some locations accompanied by intense reflected ion-beams. The electron trapping process has a periodical evolution over time due to the shock front self-reformation, which is controlled by ion dynamics. Thus, this is a cross-scale coupling phenomenon. (3) At quasi-parallel shocks, reflected ions can travel far back upstream. Consequently, quasi-electrostatic waves can be excited in the shock transition and the foreshock region. The electron trajectory analysis shows these waves can trap electrons at the foot region and reflect a fraction of them far back upstream. Simulation runs in this paper indicate that the micro-turbulence at the shock foot can provide a possible scenario for producing the reflected electron beam, which is a basic condition for the type II radio burst emission at low-Mach-number interplanetary shocks driven by Coronal Mass Ejections (CMEs).
语种	英语
内容类型	期刊论文
源URL	[http://ir.nssc.ac.cn/handle/122/6405]
专题	国家空间科学中心_空间科学部
推荐引用方式 GB/T 7714	Yang, ZW ; Lu, QM ; Liu, YD ; Wang, R. Impact of Shock Front Rippling and Self-reformation on the Electron Dynamics at Low-Mach-number Shocks[J]. ASTROPHYSICAL JOURNAL,2018,857(1):36.
APA	Yang, ZW ; Lu, QM ; Liu, YD ; Wang, R.(2018).Impact of Shock Front Rippling and Self-reformation on the Electron Dynamics at Low-Mach-number Shocks.ASTROPHYSICAL JOURNAL,857(1),36.
MLA	Yang, ZW ; Lu, QM ; Liu, YD ; Wang, R."Impact of Shock Front Rippling and Self-reformation on the Electron Dynamics at Low-Mach-number Shocks".ASTROPHYSICAL JOURNAL 857.1(2018):36.