Quasi-periodic reversals of radio polarization at 17 GHz observed in the 2002 April 21 solar event

	Quasi-periodic reversals of radio polarization at 17 GHz observed in the 2002 April 21 solar event
	Huang, GL 1; Lin J(林隽)2,3
刊名	ASTROPHYSICAL JOURNAL
	2006-03-10
卷号	639 期号:2 页码:L99-L102
关键词	polarization Sun : activity Sun : radio radiation
ISSN号	0004-637X
通讯作者	Huang, GL (reprint author), Chinese Acad Sci, Purple Mt Observ, 2 W Beijing Rd, Nanjing 210008, Peoples R China.
产权排序	第二完成单位
英文摘要	We investigate high spatial resolution radio polarization data obtained by the Nobeyama Radioheliograph (NoRH) and high time resolution data observed with the Nobeyama Radio Polarimeters (NoRP) during the well-studied flare/CME event of 2002 April 21. A 17 GHz radio source at the loop top was seen by NoRH to move upward together with the expanding flare loops at a speed of around 10 km s(-1). In the 5 minutes before the source began its upward motion, the Stokes V of the radio signals at 17 GHz showed quasi-periodic reversals between left-circular polarization (LCP) and right-circular polarization (RCP). Following this interval, the polarizations gradually turned to LCP. During this period, the polarization of the corresponding footpoint source maintained the RCP sense. The reversal of Stokes V between RCP and LCP was also detected at lower frequencies (1-2 GHz) by NoRP, without spatial resolution. The observed reversals between RCP and LCP of the radio signals from the top of the flare loop system can be taken as evidence that magnetic energy is released or energetic particles are produced at the magnetic reconnection site in a quasi-periodic fashion.
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]	CORONAL MASS EJECTION ; NOBEYAMA RADIOHELIOGRAPH ; MAGNETIC-FIELD ; X1.5 FLARE ; RHESSI ; RECONNECTION ; MICROWAVE ; BURSTS ; EMISSION ; TRACE
收录类别	SCI
原文出处	http://iopscience.iop.org/1538-4357/639/2/L99/
语种	英语
WOS记录号	WOS:000235837200014
公开日期	2016-05-03
内容类型	期刊论文
源URL	[http://ir.ynao.ac.cn/handle/114a53/6093]
专题	云南天文台_太阳物理研究组
作者单位	1.Purple Mountain Observatory, Chinese Academy of Sciences, 2 West Beijing Road, 210008 Nanjing, China 2.Yunnan Astronomical Observatory, National Astronomical Observatories, Chinese Academy of Sciences, P.O. Box 110, 650011 Kunming, China 3.Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138
推荐引用方式 GB/T 7714	Huang, GL,Lin J. Quasi-periodic reversals of radio polarization at 17 GHz observed in the 2002 April 21 solar event[J]. ASTROPHYSICAL JOURNAL,2006,639(2):L99-L102.
APA	Huang, GL,&Lin J.(2006).Quasi-periodic reversals of radio polarization at 17 GHz observed in the 2002 April 21 solar event.ASTROPHYSICAL JOURNAL,639(2),L99-L102.
MLA	Huang, GL,et al."Quasi-periodic reversals of radio polarization at 17 GHz observed in the 2002 April 21 solar event".ASTROPHYSICAL JOURNAL 639.2(2006):L99-L102.