The mass–metallicity relation of Lyman-break analogues and its dependence on galaxy properties

• Published in: Monthly notices of the Royal Astronomical Society Vol. 446; no. 2; pp. 1449 - 1457
• Main Authors: Lian, J. H., Li, J. R., Yan, W., Kong, X.
• Format: Journal Article
• Language: English
• Published: London Oxford University Press 11.01.2015
• Subjects: Astronomy; Luminosity; Physical properties; Red shift; Stars & galaxies; Universe
• ISSN: 0035-8711; 1365-2966
• DOI: 10.1093/mnras/stu2184

We investigate the mass-metallicity relation and its dependence on galaxy physical properties with a sample of 703 Lyman-break analogues (LBAs) in local Universe, which have similar properties to high-redshift star-forming galaxies. The sample is selected according to Hα luminosity,L(Hα) > 10... erg...s..., and surface brightness, I(Hα) > 10... erg...s... kpc..., criteria. The mass-metallicity relation of LBAs harmoniously agrees with that of star-forming galaxies at z ... 1.4-1.7 in stellar mass range of 10... M... < M... < 10... M... The relation between stellar mass, metallicity and star formation rate of our sample is roughly consistent with the local fundamental metallicity relation. We find that the mass-metallicity relation shows a strong correlation with the 4000 A break; galaxies with higher 4000 A break typically have higher metallicity at a fixed mass, by 0.06 dex in average. This trend is independent of the methodology of metallicity. We also use the metallicity estimated by T...-method to confirm it. The scatter in mass-metallicity relation can be reduced from 0.091 to 0.077 dex by a three-dimensional relation between stellar mass, metallicity and 4000 A break. The reduction of scatter in mass-metallicity relation suggests that the galaxy stellar age plays an important role as the second parameter in the mass-metallicity relation of LBAs. (ProQuest: ... denotes formulae/symbols omitted.)