A solar type U burst in the decimetric range

	A solar type U burst in the decimetric range
	Yao, JX ; Yu, XF ; Tlamicha, A ; Wei, FS ; Antonucci, E ; Shea, MA
刊名	SUN AND ITS ATMOSPHERE
	1997
卷号	20 期号:12 页码:2351-2354
ISSN号	0273-1177
英文摘要	This paper analyzes a Type U burst at 1.0-2.8 GHz which occurred between 12:36:26 - 12:36:32 UT on 1992 August 22, observed by Ondfejov Observatory, Czech Republic. This may be the first example of Type U bursts in the decimetric range, as far as we know. From analysis we came to the following conclusion: (1) The frequency-drift rates of the ascending and descending branches are 1.25 and 0.225 GHz/s, respectively, and the velocities of the electron beam are 0.38 c and 0.26 c, respectively; (2) The burst decay of the ascending branch is larger than that of the descending branch; (3) The variations of the maximum frequencies of instantaneous spectra with time appear as from the highest (1.92 GHz) to the lowest (1.0 GHz), then toward higher frequency (1.53 GHz) (this is consistent with that predicted by plasma emission theory); (4) The bandwidths of the ascending branch are about twice that of the descending branch (this may be caused by the larger drift rates of the ascending branch); (5) The temperature of the coronal loop apex is 6.3 x 10(6) K; (6) The magnetic field at the top of the loop is greater than 9.2 G; (7) This U burst emission is plasma radiation at the second harmonic (C) 1997 COSPAR. Published by Elsevier Science Ltd.
学科主题	Engineering ; Astronomy & Astrophysics ; Geology ; Meteorology & Atmospheric Sciences
WOS标题词	Science & Technology ; Technology ; Physical Sciences
类目[WOS]	Engineering, Aerospace ; Astronomy & Astrophysics ; Geosciences, Multidisciplinary ; Meteorology & Atmospheric Sciences
研究领域[WOS]	Engineering ; Astronomy & Astrophysics ; Geology ; Meteorology & Atmospheric Sciences
收录类别	ISTP ; SCI
语种	英语
WOS记录号	WOS:000071955600025
公开日期	2013-02-05
内容类型	期刊论文
源URL	[http://libir.pmo.ac.cn/handle/332002/8427]
专题	紫金山天文台_期刊（老文献）
作者单位	1.Chinese Acad Sci, Purple Mt Observ, Nanjing 210008, Peoples R China 2.Astron Inst Ondrejov Observ, Ondrejov 25165, Czech Republic 3.Chinese Acad Sci, Lab Numer Study Heliospher Phys, Beijing 100080, Peoples R China
推荐引用方式 GB/T 7714	Yao, JX,Yu, XF,Tlamicha, A,et al. A solar type U burst in the decimetric range[J]. SUN AND ITS ATMOSPHERE,1997,20(12):2351-2354.
APA	Yao, JX,Yu, XF,Tlamicha, A,Wei, FS,Antonucci, E,&Shea, MA.(1997).A solar type U burst in the decimetric range.SUN AND ITS ATMOSPHERE,20(12),2351-2354.
MLA	Yao, JX,et al."A solar type U burst in the decimetric range".SUN AND ITS ATMOSPHERE 20.12(1997):2351-2354.