Energetic electrons in loop top and footpoint microwave sources

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

	Energetic electrons in loop top and footpoint microwave sources
	Zhou, AH ; Su, YN; Huang, GL
刊名	SOLAR PHYSICS
	2005-02-01
卷号	226 期号:2 页码:327-336
关键词	HARD X-RAY SOLAR-FLARES FLARING LOOP GYROSYNCHROTRON RADIATION IMPULSIVE PHASE EMISSION BURSTS FIELD CONFIGURATION POLARIZATION
ISSN号	0038-0938
英文摘要	We have studied two microwave events with one-loop top (LT) and two-footpoint (FP) sources observed at 17 and 34 GHz by the Nobeyama Radioheliograph (NoRH). The microwave brightness peak is located near the FPs of the flare loop for one event, but near the LT for the other event. The microwave spectra of the FP sources are considerably softer (by Delta alpha approximate to 2.0) than that of the LTs for both events. We assume that the microwave emission is gyro-synchrotron radiation from energetic electrons trapped in a magnetic dipole field and the energetic electron distribution is isotropic in pitch angle and power law. In the gyro-synchrotron calculations, the self-absorption and gyro-resonance absorption are taken into account simultaneously. The numerical calculations based on the general equation of radiative transfer show that the distributions of energetic electrons along a flare loop are highly inhomogeneous: accelerated electrons are concentrated in the FPs for both events. Even for the event with brightness maximum near the LT the electron number density of the LT source is still an order of magnitude lower than that of the FP sources. The emission peak near LT results mainly from the much harder spectral index of the energetic electrons in the LT source.
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]	HARD X-RAY ; SOLAR-FLARES ; FLARING LOOP ; GYROSYNCHROTRON RADIATION ; IMPULSIVE PHASE ; EMISSION ; BURSTS ; FIELD ; CONFIGURATION ; POLARIZATION
收录类别	SCI
语种	英语
WOS记录号	WOS:000229188200008
公开日期	2012-03-07
内容类型	期刊论文
源URL	[http://159.226.72.40/handle/332002/4144]
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.Chinese Acad Sci, Purple Mt Observ, Nanjing 210008, Peoples R China 2.Chinese Acad Sci, Grad Sch, Beijing 100864, Peoples R China
推荐引用方式 GB/T 7714	Zhou, AH,Su, YN,Huang, GL. Energetic electrons in loop top and footpoint microwave sources[J]. SOLAR PHYSICS,2005,226(2):327-336.
APA	Zhou, AH,Su, YN,&Huang, GL.(2005).Energetic electrons in loop top and footpoint microwave sources.SOLAR PHYSICS,226(2),327-336.
MLA	Zhou, AH,et al."Energetic electrons in loop top and footpoint microwave sources".SOLAR PHYSICS 226.2(2005):327-336.