The galaxy stellar mass function and low surface brightness galaxies from core-collapse supernovae

• Published in: Monthly notices of the Royal Astronomical Society Vol. 484; no. 4; pp. 5278 - 5295
• Main Authors: Sedgwick, Thomas M, Baldry, Ivan K, James, Philip A, Kelvin, Lee S
• Format: Journal Article
• Language: English
• Published: Oxford University Press 21-04-2019
• Subjects: methods: statistical; galaxies: luminosity function, mass function; supernovae: general; galaxies: distances and redshifts; galaxies: star formation
• ISSN: 0035-8711; 1365-2966
• DOI: 10.1093/mnras/stz186

Abstract
We introduce a method for producing a galaxy sample unbiased by surface brightness and stellar mass, by selecting star-forming galaxies via the positions of core-collapse supernovae (CCSNe). Whilst matching ∼2400 supernovae from the SDSS-II Supernova Survey to their host galaxies using IAC Stripe 82 legacy coadded imaging, we find ∼150 previously unidentified low surface brightness galaxies (LSBGs). Using a sub-sample of ∼900 CCSNe, we infer CCSN-rate and star formation rate densities as a function of galaxy stellar mass, and the star-forming galaxy stellar mass function. Resultant star-forming galaxy number densities are found to increase following a power law down to our low-mass limit of ∼106.4 M⊙ by a single Schechter function with a faint-end slope of α = −1.41. Number densities are consistent with those found by the EAGLE simulations invoking a Λ cold dark matter cosmology. Overcoming surface brightness and stellar mass biases is important for assessment of the sub-structure problem. In order to estimate galaxy stellar masses, a new code for the calculation of galaxy photometric redshifts, zMedIC, is also presented, and shown to be particularly useful for small samples of galaxies.