Molecular lines and continuum from W51A (I) - CO and NH3 spectra and 3 mm continuum

CORC > 紫金山天文台 > 中国科学院紫金山天文台 > 分子云与恒星形成研究团组

	Molecular lines and continuum from W51A (I) - CO and NH3 spectra and 3 mm continuum
	Pei, CC ; Mao, RQ; Zeng, Q
刊名	SCIENCE IN CHINA SERIES A-MATHEMATICS PHYSICS ASTRONOMY
	2001-09-01
卷号	44 期号:9 页码:1209-1215
关键词	massive star formation molecular cloud collapse interstellar molecular lines continuum
ISSN号	1006-9283
英文摘要	As for the 5' x 4'( similar to 11pc x 9pc) region centered at W51 IRS1 the observations of the 3.4 mm continuum, CO ( J = 1-0) line and simultaneous NH3 (1,1) (2,2), (3,3), (4,4) inverse lines were made for studying the massive star formation region located in the main spiral arms of the Galaxy. In the directions of W51 IRS1, IRS2 and e1/e2 in 3.4 mm continuum, analyses of the line profiles show that the absorption lines of ammonia, which arise from the gas in front of the HII region, are red-shifted with respect to the emission lines, which arise from the surrounding cloud. Furthermore, a radiation transfer and statistical equilibrium calculation of ammonia molecules show that the densities increase by 3-10 times from the eastern border to the center. These points hint that the collapse is happening in the molecular cloud core obscured in optical wavelengths. The effects of the radiation fields from radio, infrared and UCHII sources is non-negligible on the excitation of various molecules (e.g. NH3) within the circle of radius 40" centered at IRS1. The profiles of the CO J = 1-0 line in the circle change from double peaks ( similar to 60, similar to 68 km (.) s(-1)) to triple peaks, i. e. the component similar to 53 km (.) s(-1), which associates with UCHII, also appears in the spectra. There are indications that the circle of radius 40" centered at IRS1 is a region of massive star forming activity.
学科主题	Astronomy & Astrophysics
WOS标题词	Science & Technology ; Physical Sciences
类目[WOS]	Mathematics, Applied ; Mathematics
研究领域[WOS]	Mathematics
关键词[WOS]	DYNAMICAL COLLAPSE ; MASSIVE CORES
收录类别	SCI
语种	英语
WOS记录号	WOS:000174374500017
公开日期	2013-01-31
内容类型	期刊论文
源URL	[http://libir.pmo.ac.cn/handle/332002/8182]
专题	紫金山天文台_分子云与恒星形成研究团组
作者单位	1.Chinese Acad Sci, Purple Mtn Observ, Nanjing 210008, Peoples R China 2.Chinese Acad Sci, Natl Astronom Observ, Beijing 100080, Peoples R China
推荐引用方式 GB/T 7714	Pei, CC,Mao, RQ,Zeng, Q. Molecular lines and continuum from W51A (I) - CO and NH3 spectra and 3 mm continuum[J]. SCIENCE IN CHINA SERIES A-MATHEMATICS PHYSICS ASTRONOMY,2001,44(9):1209-1215.
APA	Pei, CC,Mao, RQ,&Zeng, Q.(2001).Molecular lines and continuum from W51A (I) - CO and NH3 spectra and 3 mm continuum.SCIENCE IN CHINA SERIES A-MATHEMATICS PHYSICS ASTRONOMY,44(9),1209-1215.
MLA	Pei, CC,et al."Molecular lines and continuum from W51A (I) - CO and NH3 spectra and 3 mm continuum".SCIENCE IN CHINA SERIES A-MATHEMATICS PHYSICS ASTRONOMY 44.9(2001):1209-1215.