The global star formation law of galaxies revisited in the radio continuum

CORC > 紫金山天文台 > 中国科学院紫金山天文台 > 星系中的恒星形成研究团组

	The global star formation law of galaxies revisited in the radio continuum
	Liu LiJie 1,2; Gao Yu1
刊名	SCIENCE CHINA-PHYSICS MECHANICS & ASTRONOMY
	2012-02-01
卷号	55 期号:2 页码:347-353
关键词	galaxies: evolation galaxies: ISM radio lines: galaxies stars: fromation
ISSN号	1674-7348
英文摘要	We study the global star formation law, the relation between the gas and star formation rate (SFR) in a sample of 130 local galaxies with infrared (IR) luminosities spanning over three orders of magnitude (10(9)-10(12) L-aS (TM)), which includes 91 normal spiral galaxies and 39 (ultra)luminous IR galaxies [(U)LIRGs]. We derive their total (atomic and molecular) gas and dense molecular gas masses using newly available HI, CO and HCN data from the literature. The SFR of galaxies is determined from total IR (8-1000 mu m) and 1.4 GHz radio continuum (RC) luminosities. The galaxy disk sizes are defined by the de-convolved elliptical Gaussian FWHM of the RC maps. We derive the galaxy disk-averaged SFRs and various gas surface densities, and investigate their relationships. We find that the galaxy disk-averaged surface density of dense molecular gas mass has the tightest correlation with that of SFR (scatter similar to 0.26 dex), and is linear in log-log space (power-law slope of N=1.03 +/- 0.02) across the full galaxy sample. The correlation between the total gas and SFR surface densities for the full sample has a somewhat larger scatter (similar to 0.48 dex), and is best fit by a power-law with slope 1.45 +/- 0.02. However, the slope changes from similar to 1 when only normal spirals are considered, to similar to 1.5 when more and more (U)LIRGs are included in the fitting. When different CO-to-H-2 conversion factors are used to infer molecular gas masses for normal galaxies and (U)LIRGs, the bi-modal relations claimed recently in CO observations of high-redshift galaxies appear to also exist in local populations of star-forming galaxies.
学科主题	Astronomy & Astrophysics
WOS标题词	Science & Technology ; Physical Sciences
类目[WOS]	Physics, Multidisciplinary
研究领域[WOS]	Physics
关键词[WOS]	DENSE MOLECULAR GAS ; ULTRALUMINOUS INFRARED GALAXIES ; HIGH-REDSHIFT ; FORMING GALAXIES ; NEARBY GALAXIES ; SPIRAL GALAXIES ; HCN ; STARBURSTS ; SAMPLE ; CO
收录类别	SCI
语种	英语
WOS记录号	WOS:000299295500023
公开日期	2013-01-31
内容类型	期刊论文
源URL	[http://libir.pmo.ac.cn/handle/332002/8076]
专题	紫金山天文台_星系中的恒星形成研究团组
作者单位	1.Chinese Acad Sci, Purple Mt Observ, Nanjing 210008, Peoples R China 2.Chinese Acad Sci, Grad Univ, Beijing 100039, Peoples R China
推荐引用方式 GB/T 7714	Liu LiJie,Gao Yu. The global star formation law of galaxies revisited in the radio continuum[J]. SCIENCE CHINA-PHYSICS MECHANICS & ASTRONOMY,2012,55(2):347-353.
APA	Liu LiJie,&Gao Yu.(2012).The global star formation law of galaxies revisited in the radio continuum.SCIENCE CHINA-PHYSICS MECHANICS & ASTRONOMY,55(2),347-353.
MLA	Liu LiJie,et al."The global star formation law of galaxies revisited in the radio continuum".SCIENCE CHINA-PHYSICS MECHANICS & ASTRONOMY 55.2(2012):347-353.