Discovery of an extremely red galaxy at z=0.65 with dusty star formation and nuclear activity

In the course of the follow-up multiwavelength study of a deep radio survey, we have discovered that the millijansky radio source PDF J011423 is a low-redshift (z = 0.65) extremely red galaxy (ERG) with K = 15.3, R-K = 5.8, and J-K = 3.1. Optical, infrared, and radio photometry, together with optical and near-infrared spectroscopy, reveal a heavily obscured galaxy (A(v) = 5-6, from the observed Balmer decrement) undergoing vigorous star formation and presenting an active galactic nucleus. PDF J011423 is a representative member of the dusty ERG population, providing a local counterpart for studying more distant ERGs.