Characterizing uniform star formation efficiencies with marginally stable galactic discs

	Characterizing uniform star formation efficiencies with marginally stable galactic discs
	Wong, O. Ivy 1,2; Meurer, G. R.1,3; Zheng, Z.4 ; Heckman, T. M.5; Thilker, D. A.5; Zwaan, M. A.6
刊名	MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
	2016-07-21
卷号	460 期号:1 页码:1106-1118
关键词	galaxies: dwarf galaxies: evolution galaxies: formation galaxies: ISM galaxies: spiral galaxies: structure
英文摘要	We examine the HI-based star formation efficiency (SFEHI), the ratio of star formation rate to the atomic hydrogen (H I) mass, in the context of a constant stability star-forming disc model. Our observations of HI-selected galaxies show SFEHI to be fairly constant (log SFEHI = -9.65 yr(-1) with a dispersion of 0.3 dex) across similar to 5 orders of magnitude in stellar masses. We present a model to account for this result, whose main principle is that the gas within galaxies forms a uniform stability disc and that stars form within the molecular gas in this disc. We test two versions of the model differing in the prescription that determines the molecular gas fraction, based on either the hydrostatic pressure or the stellar surface density of the disc. For high-mass galaxies such as the Milky Way, we find that either prescription predicts SFEHI similar to the observations. However, the hydrostatic pressure prescription is a more accurate SFEHI predictor for low-mass galaxies. Our model is the first model that links the uniform SFEHI observed in galaxies at low redshifts to star-forming discs with constant marginal stability. While the rotational amplitude Vmax is the primary driver of disc structure in our model, we find that the specific angular momentum of the galaxy may play a role in explaining a weak correlation between SFEHI and effective surface brightness of the disc.
收录类别	SCI
语种	英语
WOS记录号	WOS:000379835200075
内容类型	期刊论文
源URL	[http://ir.bao.ac.cn/handle/114a11/5294]
专题	国家天文台_星系宇宙学研究部
作者单位	1.Int Ctr Radio Astron Res, ICRAR M468,35 Stirling Highway, Crawley, WA 6009, Australia 2.ARC Ctr Excellence All Sky Astrophys CAASTRO, Redfern, NSW, Australia 3.Univ Western Australia, Sch Phys, 35 Stirling Highway, Crawley, WA 6009, Australia 4.Chinese Acad Sci, Natl Astron Observ, 20A Datun Rd, Beijing 100012, Peoples R China 5.Johns Hopkins Univ, Dept Phys & Astron, 3701 San Martin Dr, Baltimore, MD 21218 USA 6.European Southern Observ, Karl Schwarzschild Str 2, D-85748 Garching, Germany
推荐引用方式 GB/T 7714	Wong, O. Ivy,Meurer, G. R.,Zheng, Z.,et al. Characterizing uniform star formation efficiencies with marginally stable galactic discs[J]. MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY,2016,460(1):1106-1118.
APA	Wong, O. Ivy,Meurer, G. R.,Zheng, Z.,Heckman, T. M.,Thilker, D. A.,&Zwaan, M. A..(2016).Characterizing uniform star formation efficiencies with marginally stable galactic discs.MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY,460(1),1106-1118.
MLA	Wong, O. Ivy,et al."Characterizing uniform star formation efficiencies with marginally stable galactic discs".MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY 460.1(2016):1106-1118.