Effects of Shock and Turbulence Properties on Electron Acceleration

doi:10.3847/1538-4357/aac26f

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	Effects of Shock and Turbulence Properties on Electron Acceleration
	Qin,G.2; Kong,F.-J.1,3; Zhang,L.-H.3,4
刊名	The Astrophysical Journal
	2018-06-06
卷号	860 期号:1
关键词	acceleration of particles plasmas shock waves Sun: coronal mass ejections (CMEs) Sun: particle emission turbulence
ISSN号	0004-637X
DOI	10.3847/1538-4357/aac26f
英文摘要	Abstract Using test particle simulations, we study electron acceleration at collisionless shocks with a two-component model turbulent magnetic field with slab component including dissipation range. We investigate the importance of the shock-normal angle θBn, magnetic turbulence level , and shock thickness on the acceleration efficiency of electrons. It is shown that at perpendicular shocks the electron acceleration efficiency is enhanced with the decrease of , and at the acceleration becomes significant due to a strong drift electric field with long time particles staying near the shock front for shock drift acceleration (SDA). In addition, at parallel shocks the electron acceleration efficiency is increasing with the increase of , and at the acceleration is very strong due to sufficient pitch-angle scattering for first-order Fermi acceleration, as well as due to the large local component of the magnetic field perpendicular to the shock-normal angle for SDA. On the other hand, the high perpendicular shock acceleration with is stronger than the high parallel shock acceleration with , the reason might be the assumption that SDA is more efficient than first-order Fermi acceleration. Furthermore, for oblique shocks, the acceleration efficiency is small no matter whether the turbulence level is low or high. Moreover, for the effect of shock thickness on electron acceleration at perpendicular shocks, we show that there exists the bendover thickness, Ldiff,b. The acceleration efficiency does not noticeably change if the shock thickness is much smaller than Ldiff,b. However, if the shock thickness is much larger than Ldiff,b, the acceleration efficiency starts to drop abruptly.
语种	英语
出版者	The American Astronomical Society
WOS记录号	IOP:0004-637X-860-1-AAC26F
内容类型	期刊论文
源URL	[http://ir.bao.ac.cn/handle/114a11/21750]
专题	中国科学院国家天文台
作者单位	1.College of Earth Sciences, University of Chinese Academy of Sciences, Beijing 100049, People’s Republic of China 2.School of Science, Harbin Institute of Technology, Shenzhen 518055, People’s Republic of China; qingang@hit.edu.cn 3.State Key Laboratory of Space Weather, National Space Science Center, Chinese Academy of Sciences, Beijing 100190, People’s Republic of China 4.Key Laboratory of Solar Activity, National Astronomical Observatories, Chinese Academy of Sciences, Beijing 100012, People’s Republic of China
推荐引用方式 GB/T 7714	Qin,G.,Kong,F.-J.,Zhang,L.-H.. Effects of Shock and Turbulence Properties on Electron Acceleration[J]. The Astrophysical Journal,2018,860(1).
APA	Qin,G.,Kong,F.-J.,&Zhang,L.-H..(2018).Effects of Shock and Turbulence Properties on Electron Acceleration.The Astrophysical Journal,860(1).
MLA	Qin,G.,et al."Effects of Shock and Turbulence Properties on Electron Acceleration".The Astrophysical Journal 860.1(2018).