2007/01/26 by Sheila J. Kannappan, Eric Gawiser · 1 citation
Physics and Astronomy · #astro-ph
paper · pdf · doi:10.1086/512974
published as Astrophys.J.657:L5-L8,2007 · 5 pages including 2 enlarged figures, ApJ Letters, accepted
arxiv created 2007/01/26 · arxiv updated 2009/12/01
We show that different stellar-mass estimation methods yield overall mass scales that disagree by factors up to ~2 for the z=0 galaxy population, and more importantly, relative mass scales that sometimes disagree by factors >~3 between distinct classes of galaxies (spiral/irregular types, classical E/S0s, and E/S0s whose colors reflect recent star formation). This comparison considers stellar mass estimates based on (a) two different calibrations of the correlation between K-band mass-to-light ratio and B-R color (Bell et al., Portinari et al.) and (b) detailed fitting of UBRJHK photometry and optical spectrophotometry using two different population synthesis models (Bruzual-Charlot, Maraston), with the same initial mass function in all cases. We also compare stellar+gas masses with dynamical masses. This analysis offers only weak arguments for preferring a particular stellar-mass estimation method, given the plausibility of real variations in dynamical properties and dark matter content. These results help to calibrate the systematic uncertainties inherent in mass-based evolutionary studies of galaxies, including comparisons of low and high redshift galaxies.