FROM LARGE-SCALE LOOPS TO THE SITES OF DENSE FLARING LOOPS: PREFERENTIAL CONDITIONS FOR LONG-PERIOD PULSATIONS IN SOLAR FLARES

	FROM LARGE-SCALE LOOPS TO THE SITES OF DENSE FLARING LOOPS: PREFERENTIAL CONDITIONS FOR LONG-PERIOD PULSATIONS IN SOLAR FLARES
	Foullon, C.1; Fletcher, L.2; Hannah, I. G.2; Verwichte, E.1; Cecconi, B.3; Nakariakov, V. M.1; Phillips, K. J. H.4; Tan, B. L.5
刊名	ASTROPHYSICAL JOURNAL
	2010-08-10
卷号	719 期号:1 页码:151-165
关键词	Sun: corona Sun: flares Sun: oscillations Sun: particle emission Sun: radio radiation Sun: X-rays, gamma rays
英文摘要	Long-period quasi-periodic pulsations (QPPs) of solar flares are a class apart from shorter period events. By involving an external resonator, the mechanism they call upon differs from traditional QPP models, but has wider applications. We present a multi-wavelength analysis of spatially resolved QPPs, with periods around 10 minutes, observed in the X-ray spectrum primarily at energies between 3 and 25 keV. Complementary observations obtained in H alpha and radio emission in the kHz to GHz frequency range, together with an analysis of the X-ray plasma properties provide a comprehensive picture that is consistent with a dense flaring loop subject to periodic energization and thermalization. The QPPs obtained in H alpha and type III radio bursts, with similar periods as the QPPs in soft X-rays, have the longest periods ever reported for those types of data sets. We also report 1-2 GHz radio emission, concurrent with but unrestricted to the QPP time intervals, which is multi-structured at regularly separated narrowband frequencies and modulated with similar to 18 minute periods. This radio emission can be attributed to the presence of multiple "quiet" large-scale loops in the background corona. Large scale but shorter inner loops below may act as preferential resonators for the QPPs. The observations support interpretations consistent with both inner and outer loops subject to fast kink magnetohydrodynamic waves. Finally, X-ray imaging indicates the presence of double coronal sources in the flaring sites, which could be the particular signatures of the magnetically linked inner loops. We discuss the preferential conditions and the driving mechanisms causing the repeated flaring.
收录类别	SCI
语种	英语
WOS记录号	WOS:000280653100014
内容类型	期刊论文
源URL	[http://ir.bao.ac.cn/handle/114a11/7685]
专题	国家天文台_太阳物理研究部
作者单位	1.Univ Warwick, Dept Phys, Ctr Fus Space & Astrophys, Coventry CV4 7AL, W Midlands, England 2.Univ Glasgow, Dept Phys & Astron, Glasgow G12 8QQ, Lanark, Scotland 3.Univ Paris Diderot, Observ Paris, UPMC, CNRS,LESIA, F-92190 Meudon, France 4.Univ Coll London, Mullard Space Sci Lab, Dorking RH5 6NT, Surrey, England 5.Chinese Acad Sci, Natl Astron Observ, Key Lab Solar Act, Beijing 100012, Peoples R China
推荐引用方式 GB/T 7714	Foullon, C.,Fletcher, L.,Hannah, I. G.,et al. FROM LARGE-SCALE LOOPS TO THE SITES OF DENSE FLARING LOOPS: PREFERENTIAL CONDITIONS FOR LONG-PERIOD PULSATIONS IN SOLAR FLARES[J]. ASTROPHYSICAL JOURNAL,2010,719(1):151-165.
APA	Foullon, C..,Fletcher, L..,Hannah, I. G..,Verwichte, E..,Cecconi, B..,...&Tan, B. L..(2010).FROM LARGE-SCALE LOOPS TO THE SITES OF DENSE FLARING LOOPS: PREFERENTIAL CONDITIONS FOR LONG-PERIOD PULSATIONS IN SOLAR FLARES.ASTROPHYSICAL JOURNAL,719(1),151-165.
MLA	Foullon, C.,et al."FROM LARGE-SCALE LOOPS TO THE SITES OF DENSE FLARING LOOPS: PREFERENTIAL CONDITIONS FOR LONG-PERIOD PULSATIONS IN SOLAR FLARES".ASTROPHYSICAL JOURNAL 719.1(2010):151-165.