Statistical study of photospheric bright points in an active region and quiet Sun

	Statistical study of photospheric bright points in an active region and quiet Sun
	Feng, S 1,2,3; Deng LH(邓林华)4,5 ; Yang, YF 1,2,3; Ji, KF1
刊名	ASTROPHYSICS AND SPACE SCIENCE
	2013-11
卷号	348 期号:1 页码:17-24
关键词	Techniques: image processing Sun: granulation Sun: photosphere Methods: statistical analysis
ISSN号	0004-640X
通讯作者	Ji, KF (reprint author), Kunming Univ Sci & Technol, Comp Technol Applicat Key Lab Yunnan Prov, Kunming 650500, Peoples R China.
产权排序	第四完成单位
英文摘要	The statistical properties of photospheric bright points (PBPs) in active regions (ARs) and the quiet Sun (QS) are investigated using two data sets obtained with the Dutch Open Telescope. Data for AR NOAA 10642 (July 12, 2004) and the QS (October 19, 2005) near the disk center are analyzed. For extracting PBPs, an automatic algorithm, employing Laplacian and morphological dilation (LMD) technique, is developed. The statistical properties of PBPs such as size distribution, contrast between maximum of PBPs and mean photospheric intensity, area coverage, number coverage and geometric shape are quantified. We then use goodness-of-fit to evaluate the fit of the size distribution of PBPs in the two regions. Finally, the Kolmogorov-Smirnov test is used to analyze the statistical difference in the AR and the QS. The following results are obtained: (1) the size distributions (probability density function) of PBPs in the two regions follow a lognormal distribution, moreover they are from the same size distribution; (2) the number coverage and the area coverage in the AR are about twice larger than those in the QS, respectively; (3) the geometrical shape of PBPs is quantified by the ratio of the length of major axis to the length of minor axis by the center of gravity. The ratio of about 50 % PBPs is less than 1.5, and their geometrical shapes are exactly alike in the two regions; (4) the ratio of maximum intensity of PBPs to their corresponding mean photospheric intensity is larger in the AR than in the QS. The results suggest that size and shape of PBPs in the AR and the QS are just the same, but the brightness of PBPs in the AR is different from that in the QS.
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]	G-BAND STRUCTURES ; FINE-STRUCTURE ; MAGNETIC-FLUX ; SIZE ; TELESCOPE ; FEATURES ; ELEMENTS
收录类别	SCI
原文出处	http://link.springer.com/article/10.1007%2Fs10509-013-1555-6
语种	英语
WOS记录号	WOS:000326598500003
内容类型	期刊论文
源URL	[http://ir.ynao.ac.cn/handle/114a53/4689]
专题	云南天文台_抚仙湖太阳观测站
作者单位	1.Computer Technology Application Key Lab of Yunnan Province, Kunming University of Science and Technology, Kunming, 650500, China 2.Key Laboratory of Solar Activity, National Astronomical Observatories, Chinese Academy of Sciences, Beijing, 100012, China 3.Key Laboratory of Modern Astronomy and Astrophysics (Nanjing University), Ministry of Education, Nanjing, 210093, China 4.Yunnan Astronomical Observatory, Chinese Academy of Sciences, Kunming, 650011, China 5.University of Chinese Academy of Sciences, Beijing, 100049, China
推荐引用方式 GB/T 7714	Feng, S,Deng LH,Yang, YF,et al. Statistical study of photospheric bright points in an active region and quiet Sun[J]. ASTROPHYSICS AND SPACE SCIENCE,2013,348(1):17-24.
APA	Feng, S,Deng LH,Yang, YF,&Ji, KF.(2013).Statistical study of photospheric bright points in an active region and quiet Sun.ASTROPHYSICS AND SPACE SCIENCE,348(1),17-24.
MLA	Feng, S,et al."Statistical study of photospheric bright points in an active region and quiet Sun".ASTROPHYSICS AND SPACE SCIENCE 348.1(2013):17-24.