We have determined K-band luminosity functions for 13,325 local universe galaxies as a function of morphology and color (for Ktot≤10.75). Our sample is drawn from the Two Micron All Sky Survey Extended Source Catalog, with all sample galaxies having measured morphologies and distances (including 4219 archival redshift-independent distances). The luminosity function for our total sample is in good agreement with previous works, but is relatively smooth at faint magnitudes (due to bulk flow distance corrections). We investigated the differences due to morphological and color selection using 5417 sample galaxies with NASA Sloan Atlas optical colors and find that red spirals comprise 20%–50% of all spirals with −25 ≤ MK < −20. Fainter than MK = −24, red spirals are as common as early types, explaining the different faint end slopes (α = −0.87 and −1.00 for red and early-types, respectively). While we find red spirals comprise more than 50% of all MK < −25 spiral galaxies, they do not dominate the bright end of the overall red galaxy luminosity function, which is dominated by early-type galaxies. The brightest red spirals have ongoing star formation and those without are frequently misclassified as early-types. The faintest ones have an appearance and Sersic indices consistent with faded disks, rather than true bulge-dominated galaxies.
Bibliographical noteCopyright 2015 The American Astronomical Society. First published in the Astrophysical journal, 799(2), 160, 2015, published by IOP Publishing. The original publication is available at http://www.doi.org/10.1088/0004-637X/799/2/160. Version archived for private and non-commercial use with the permission of the author/s and according to publisher conditions. For further rights please contact the publisher.
- galaxies: evolution
- galaxies: luminosity function, mass function
- galaxies: star formation