NUMERICAL EXPERIMENTS ON THE DETAILED ENERGY CONVERSION AND SPECTRUM STUDIES IN A CORONA CURRENT SHEET

	NUMERICAL EXPERIMENTS ON THE DETAILED ENERGY CONVERSION AND SPECTRUM STUDIES IN A CORONA CURRENT SHEET
	Ni L(倪蕾)1,2 ; Lin J(林隽)1 ; Mei ZX(梅志星)1 ; Li Y(李燕)1
刊名	ASTROPHYSICAL JOURNAL
	2015-10-20
卷号	812 期号:2
关键词	magnetic reconnection methods: numerical magnetohydrodynamics (MHD) shock waves Sun: corona
ISSN号	0004-637X
通讯作者	Ni, L (reprint author), Chinese Acad Sci, Yunnan Observ, POB 110, Kunming 650011, Yunnan, Peoples R China.
产权排序	第一完成单位
英文摘要	In this paper, we study the energy conversion and spectra in a corona current sheet (CS) by 2.5 dimensional MHD numerical simulations. Numerical results show that many Petschek-like fine structures with slow-mode shocks mediated by plasmoid instabilities develop during the magnetic reconnection process. The termination shocks can also be formed above the primary magnetic island and at the head of secondary islands. These shocks play important roles in generating thermal energy in a corona CS. For a numerical simulation with initial conditions close to the solar corona environment, the ratio of the generated thermal energy to the total dissipated magnetic energy is around 1/5 before secondary islands appear. After secondary islands appear, the generated thermal energy starts to increase sharply and this ratio can reach a value of about 3/5. In an environment with a relatively lower plasma density and plasma beta, the plasma can be heated to a much higher temperature. After secondary islands appear, the one-dimensional energy spectra along the CS do not behave as a simple power law and the spectrum index increases with the wave number. The average spectrum index for the magnetic energy spectrum along the CS is about 1.8. The two-dimensional spectra intuitively show that part of the high energy is cascaded to large kx and ky space after secondary islands appear. The plasmoid distribution function calculated from numerical simulations behaves as a power law closer to f (psi) similar to psi(-1) in the intermediate psi regime. By using eta(eff) = v(inflow) . L, the effective magnetic diffusivity is estimated to be about 10(11) similar to 10(12) m(2) s(-1).
学科主题	Astronomy & Astrophysics
WOS标题词	Science & Technology ; Physical Sciences
类目[WOS]	Astronomy & Astrophysics
研究领域[WOS]	Astronomy & Astrophysics
关键词[WOS]	CURRENT-LAYER FRAGMENTATION ; EJECTION CURRENT SHEETS ; BAND DM-SPIKES ; X-RAY SOURCE ; SOLAR-FLARE ; MAGNETIC RECONNECTION ; CASCADING RECONNECTION ; KELVIN-HELMHOLTZ ; SUPRA-ARCADE ; ERUPTION
收录类别	SCI
原文出处	http://iopscience.iop.org/article/10.1088/0004-637X/812/2/92/meta
语种	英语
WOS记录号	WOS:000365206600004
内容类型	期刊论文
源URL	[http://ir.ynao.ac.cn/handle/114a53/6262]
专题	云南天文台_太阳物理研究组
作者单位	1.Yunnan Observatories, Chinese Academy of Sciences, P.O. Box 110, Kunming, Yunnan 650011, China 2.Key Laboratory of Solar Activity, National Astronomical Observatories, Chinese Academy of Sciences, Beijing 100012, China
推荐引用方式 GB/T 7714	Ni L,Lin J,Mei ZX,et al. NUMERICAL EXPERIMENTS ON THE DETAILED ENERGY CONVERSION AND SPECTRUM STUDIES IN A CORONA CURRENT SHEET[J]. ASTROPHYSICAL JOURNAL,2015,812(2).
APA	Ni L,Lin J,Mei ZX,&Li Y.(2015).NUMERICAL EXPERIMENTS ON THE DETAILED ENERGY CONVERSION AND SPECTRUM STUDIES IN A CORONA CURRENT SHEET.ASTROPHYSICAL JOURNAL,812(2).
MLA	Ni L,et al."NUMERICAL EXPERIMENTS ON THE DETAILED ENERGY CONVERSION AND SPECTRUM STUDIES IN A CORONA CURRENT SHEET".ASTROPHYSICAL JOURNAL 812.2(2015).