PHOTOMETRIC SELECTION OF A MASSIVE GALAXY CATALOG WITH z >= 0.55

Abstract

We present the development of a photometrically selected massive galaxy catalog, targeting Luminous Red Galaxies (LRGs) and massive blue galaxies at redshifts of z. >= 0.55. Massive galaxy candidates are selected using infrared/optical color-color cuts, with optical data from the. Sloan Digital Sky Survey (SDSS) and infrared data from "unWISE" forced photometry derived from the Wide-field Infrared Survey Explorer (WISE). The selection method is based on previously developed techniques to select LRGs with z > 0.5, and is optimized using receiver operating characteristic curves. The catalog contains 16,191,145 objects, selected over the full SDSS DR10 footprint. The redshift distribution of the resulting catalog is estimated using spectroscopic redshifts from the DEEP2 Galaxy Redshift Survey and photometric redshifts from COSMOS. Restframe U - B colors from DEEP2 are used to estimate LRG selection efficiency. Using DEEP2, the resulting catalog has an. average redshift of z - 0.65, with a. standard deviation of sigma = 2.0, and an. average restframe of. U - B = 1.0, with a. standard deviation of sigma = 0.27. Using COSMOS, the resulting catalog has an. average redshift of z = 0.60, with a standard deviation of sigma = 1.8. We estimate 34% of the catalog to be blue galaxies with z >= 0.55. An estimated 9.6% of selected objects are blue sources with redshift z < 0.55. Stellar contamination is estimated to be 1.8%.