Using the 1.6[mu]m bump to study rest-frame H-band selected galaxies at redshift 2

Abstract

In this work, we set out to test the feasibility and limitations of using the 1.6[mu]m bump as a photometric redshift indicator and selection technique using publicly available Spitzer/IRAC images in the GOODS fields. We find that color selection with IRAC bandpasses is comparable in completeness and contamination to BzK selection. Using model SEDs, we find that the shape of the 1.6[mu]m bump is robust, and photometric redshifts are not greatly affected by choice of model parameters. Comparison with spectroscopic redshifts shows photometric redshifts to be reliable. We create a rest-frame NIR selected catalog of galaxies at z ~ 2 and construct a galaxy stellar mass function (SMF). Comparisons with other SMFs at approximately the same redshift show similar results. This suggests that selection at bluer wavelengths does not miss a significant amount of stellar mass in passive galaxies. Comparison with SMFs at other redshifts shows evidence for the downsizing scenario of galaxy evolution.