Traces of the dynamic current sheet during a solar flare

CORC > 紫金山天文台 > 中国科学院紫金山天文台 > 太阳活动的多波段观测研究团组

	Traces of the dynamic current sheet during a solar flare
	Ji, HS; Wang, HM ; Goode, PR ; Jiang, YC ; Yurchyshyn, V
刊名	ASTROPHYSICAL JOURNAL
	2004-05-20
卷号	607 期号:1 页码:L55-L58
关键词	Sun : activity Sun : flares Sun : magnetic fields
ISSN号	0004-637X
英文摘要	High-cadence and high-resolution time sequences of far Halpha off-band images provide a unique tool to study the evolution of the fine structure of flare kernels. The fine structure contains important information on flare topology and the triggering mechanism. In this Letter, we concentrate on the rapid changes of the relative positions of two conjugate flare footpoints. In order to carry out this study with the highest physical precision, we use r(c) = Sigmar(j)I(j)/SigmaI(j) (I-j is the Halpha brightness at r(j)) to compute the centroid of an Halpha bright kernel region caused by solar flares. Using this, we probe the fine temporal structures connected to the distance between the centroids of two conjugate kernels of an M2.3 flare. The flare, which occurred on 2002 September 9 in NOAA Active Region 0105, was observed at Big Bear Solar Observatory at the far off-band center wavelength of Halpha - 1.3 Angstrom, with a cadence of similar to40 ms. The flare was also observed by RHESSI. The time profile of the separation distance shows an excellent anticorrelation to that of the hard X-ray (HXR) emissions in 25-50 keV, which exhibit a number of separate spikes ( the linear Pearson correlation coefficient is found to be similar to-0.83). The separation between the two centroids decreases at the rising periods of four HXR spikes, then it increases after the peak time of the flare to show the expected separation motion. The most obvious decreasing, which occurred during the first HXR peak, was confirmed by corresponding images. This implies that during the impulsive phases, the energy transported from the corona is deposited increasingly inwardly between the two kernels. This new and perhaps surprising tendency for the energy deposition can be explained as being caused by current sheet pinch motions, which, at the same time, enhance the magnetic energy reconnection rate to produce the observed HXR spikes.
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]	MODEL ; FILAMENT ; ERUPTION
收录类别	SCI
语种	英语
WOS记录号	WOS:000221524100014
公开日期	2012-12-22
内容类型	期刊论文
源URL	[http://libir.pmo.ac.cn/handle/332002/7733]
专题	紫金山天文台_太阳活动的多波段观测研究团组
作者单位	1.New Jersey Inst Technol, Big Bear Solar Observ, Big Bear City, CA 92314 USA 2.Acad Sinica, Purple Mt Observ, Nanjing 210008, Peoples R China 3.New Jersey Inst Technol, Ctr Solar & Terr Res, Newark, NJ 07102 USA
推荐引用方式 GB/T 7714	Ji, HS,Wang, HM,Goode, PR,et al. Traces of the dynamic current sheet during a solar flare[J]. ASTROPHYSICAL JOURNAL,2004,607(1):L55-L58.
APA	Ji, HS,Wang, HM,Goode, PR,Jiang, YC,&Yurchyshyn, V.(2004).Traces of the dynamic current sheet during a solar flare.ASTROPHYSICAL JOURNAL,607(1),L55-L58.
MLA	Ji, HS,et al."Traces of the dynamic current sheet during a solar flare".ASTROPHYSICAL JOURNAL 607.1(2004):L55-L58.