Millisecond microwave spikes: Statistical study and application for plasma diagnostics

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

	Millisecond microwave spikes: Statistical study and application for plasma diagnostics
	Rozhansky, I. V.1,2; Fleishman, G. D.2,3; Huang, G. -L.1
刊名	ASTROPHYSICAL JOURNAL
	2008-07-10
卷号	681 期号:2 页码:1688-1697
关键词	acceleration of particles radiation mechanisms : nonthermal sun : flares sun : radio radiation turbulence
ISSN号	0004-637X
英文摘要	We analyze a dense cluster of solar radio spikes registered at 4.5-6 GHz by the Purple Mountain Observatory spectrometer (Nanjing, China), operating in the 4.5-7.5 GHz range with 5 ms temporal resolution. To handle the data from the spectrometer, we developed a new technique that uses a nonlinear multi-Gaussian spectral fit based on X-2 criteria to extract individual spikes from the originally recorded spectra. Applying this method to the experimental raw data, we eventually identified about 3000 spikes for this event, which allows us to make a detailed statistical analysis. Various statistical characteristics of the spikes have been evaluated, including the intensity distributions, the spectral bandwidth distributions, and the distribution of the spike mean frequencies. The most striking finding of this analysis is the distributions of the spike bandwidth, which are remarkably asymmetric. To reveal the underlaying microphysics, we explore the local-trap model with the renormalized theory of spectral profiles of the electron cyclotron maser (ECM) emission peak in a source with random magnetic irregularities. The distribution of the solar spike relative bandwidths calculated within the local-trap model represents an excellent fit to the experimental data. Accordingly, the developed technique may offer a new tool with which to study very low levels of magnetic turbulence in the spike sources, when the ECM mechanism of the spike cluster is confirmed.
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]	ELECTRON-CYCLOTRON MASER ; BAND DM-SPIKES ; AURORAL KILOMETRIC RADIATION ; QUASI-LINEAR DIFFUSION ; RADIO SPIKES ; SOLAR-FLARES ; LOSS-CONE ; FINE-STRUCTURE ; APRIL 10 ; EMISSION
收录类别	SCI
语种	英语
WOS记录号	WOS:000257516000075
公开日期	2011-12-30
内容类型	期刊论文
源URL	[http://159.226.72.40/handle/332002/2021]
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.Natl Astron Observ, Purple Mt Observ, Nanjing 210008, Peoples R China 2.Ioffe Inst Phys & Technol, St Petersburg 194021, Russia 3.New Jersey Inst Technol, Newark, NJ 07102 USA
推荐引用方式 GB/T 7714	Rozhansky, I. V.,Fleishman, G. D.,Huang, G. -L.. Millisecond microwave spikes: Statistical study and application for plasma diagnostics[J]. ASTROPHYSICAL JOURNAL,2008,681(2):1688-1697.
APA	Rozhansky, I. V.,Fleishman, G. D.,&Huang, G. -L..(2008).Millisecond microwave spikes: Statistical study and application for plasma diagnostics.ASTROPHYSICAL JOURNAL,681(2),1688-1697.
MLA	Rozhansky, I. V.,et al."Millisecond microwave spikes: Statistical study and application for plasma diagnostics".ASTROPHYSICAL JOURNAL 681.2(2008):1688-1697.