Galaxy And Mass Assembly (GAMA): bivariate functions of Hα star-forming galaxies

Gunawardhana, M.L.P.; Hopkins, A.M.; Taylor, E.N.; Bland-Hawthorn, J.; Norberg, P.; Baldry, I.K.; Loveday, J.; Owers, M.S.; Wilkins, S.M.; Colless, M.; Brown, M.J.I.; Driver, S.P.; Alpaslan, M.; Brough, S.; Cluver, M.; Croom, S.; Kelvin, L.; Lara-López, M.A.; Liske, J.; López-Sánchez, A.R.; Robotham, A.S.G.

Abstract

We present bivariate luminosity and stellar mass functions of Hα star-forming galaxies drawn from the Galaxy And Mass Assembly (GAMA) survey. While optically deep spectroscopic observations of GAMA over a wide sky area enable the detection of a large number of 0.001 < SFRHα (M⊙ yr−1) < 100 galaxies, the requirement for an Hα detection in targets selected from an r-band magnitude-limited survey leads to an incompleteness due to missing optically faint star-forming galaxies. Using z < 0.1 bivariate distributions as a reference we model the higher-z distributions, thereby approximating a correction for the missing optically faint star-forming galaxies to the local star formation rate (SFR) and M M densities. Furthermore, we obtain the r-band luminosity functions (LFs) and stellar mass functions of Hα star-forming galaxies from the bivariate LFs. As our sample is selected on the basis of detected Hα emission, a direct tracer of ongoing star formation, this sample represents a true star-forming galaxy sample, and is drawn from both photometrically classified blue and red subpopulations, though mostly from the blue population. On average 20–30 per cent of red galaxies at all stellar masses are star forming, implying that these galaxies may be dusty star-forming systems.

Citation

Gunawardhana, M., Hopkins, A., Taylor, E., Bland-Hawthorn, J., Norberg, P., Baldry, I., …Robotham, A. (2015). Galaxy And Mass Assembly (GAMA): bivariate functions of Hα star-forming galaxies. Monthly Notices of the Royal Astronomical Society, 447(1), 875-901. https://doi.org/10.1093/mnras/stu2232

• Journal Article Type: Article
• Publication Date: Feb 11, 2015
• Deposit Date: Feb 3, 2016
• Publicly Available Date: Feb 11, 2016
• Journal: Monthly Notices of the Royal Astronomical Society
• Print ISSN: 0035-8711
• Electronic ISSN: 1365-2966
• Publisher: Royal Astronomical Society
• Peer Reviewed: Peer Reviewed
• Volume: 447
• Issue: 1
• Pages: 875-901
• DOI: https://doi.org/10.1093/mnras/stu2232
• Keywords: Surveys, Galaxies: evolution, Galaxies: luminosity function, mass function, Galaxies: star formation.
• Public URL: https://durham-repository.worktribe.com/output/1421029