Observational evidence for the evolution of nuclear metallicity and star formation rate with the merger stage

	Observational evidence for the evolution of nuclear metallicity and star formation rate with the merger stage
	Guo, Rui1,2,3 ; Hao, Cai-Na 3; Xia, Xiao-Yang 3; Wei, Peng2,4 ; Guo, Xin 3
刊名	RESEARCH IN ASTRONOMY AND ASTROPHYSICS
	2016-07-01
卷号	16 期号:7
关键词	galaxies: abundances galaxies: evolution galaxies: interactions galaxies: starburst galaxies: star formation infrared: galaxies
英文摘要	We investigate the evolution of nuclear gas-phase oxygen abundance and star formation rate (SFR) of local far-infrared selected star-forming galaxies along the merger sequence, as traced by their optical morphologies. The sample was drawn from a cross-correlation analysis of the IRAS Point Source Catalog Redshift Survey and 1 Jy ultraluminous infrared galaxy sample with the Sloan Digital Sky Survey Data Release 7 database. The investigation is done by comparing our sample to a control sample matched in the normalized redshift distribution in two diagnostics, which are the nuclear gas-phase metallicity vs. stellar mass and the nuclear SFR vs. stellar mass diagrams. Galaxies with different morphological types show different mass-metallicity relations (MZRs). Compared to the MZR defined by the control sample, isolated spirals have comparable metallicities with the control sample at a given stellar mass. Spirals in pairs and interacting galaxies with projected separations of r(p) > 2 0 kpc show a mild metallicity dilution of 0.02-0.03 dex. Interacting galaxieswith r(p) < 2 0 kpc, pre-mergers and advanced mergers are underabundant by similar to 0. 0 6, similar to 0. 0 5 and similar to 0. 0 4 dex, respectively. This shows an evolutionary trend that the metallicity is increasingly depressed as the merging proceeds and it is diluted most dramatically when two galaxies are closely interacting. Afterwards, the interstellar medium (ISM) is enriched when the galaxies coalesce. This is the first time that such ISM enrichment at the final coalescence stage has been observed, which demonstrates the importance of supernova explosions in affecting the nuclear metallicity. Moreover, the central SFR enhancement relative to the control sample evolves simultaneously with the nuclear gas-phase oxygen abundance. Our results support the predictions from numerical simulations.
收录类别	SCI
语种	英语
WOS记录号	WOS:000379555500013
内容类型	期刊论文
源URL	[http://ir.bao.ac.cn/handle/114a11/5297]
专题	国家天文台_光学天文研究部
作者单位	1.Chinese Acad Sci, Natl Astron Observ, Beijing 100012, Peoples R China 2.Univ Chinese Acad Sci, Beijing 100049, Peoples R China 3.Tianjin Normal Univ, Tianjin Astrophys Ctr, Tianjin 300387, Peoples R China 4.Nanjing Univ, Sch Astron & Space Sci, Nanjing 210093, Jiangsu, Peoples R China
推荐引用方式 GB/T 7714	Guo, Rui,Hao, Cai-Na,Xia, Xiao-Yang,et al. Observational evidence for the evolution of nuclear metallicity and star formation rate with the merger stage[J]. RESEARCH IN ASTRONOMY AND ASTROPHYSICS,2016,16(7).
APA	Guo, Rui,Hao, Cai-Na,Xia, Xiao-Yang,Wei, Peng,&Guo, Xin.(2016).Observational evidence for the evolution of nuclear metallicity and star formation rate with the merger stage.RESEARCH IN ASTRONOMY AND ASTROPHYSICS,16(7).
MLA	Guo, Rui,et al."Observational evidence for the evolution of nuclear metallicity and star formation rate with the merger stage".RESEARCH IN ASTRONOMY AND ASTROPHYSICS 16.7(2016).