2015ApJ...815..104D

We use Hectospec mounted on the 6.5 m MMT to carry out a redshift survey of red (,,) galaxies in the Cosmological Evolution Survey (COSMOS) field to measure the environments of massive compact quiescent galaxies at intermediate redshift. The complete magnitude limited survey includes redshifts for 1766 red galaxies with covering the central square degree of the field; 65% of the redshifts in this sample are new. We select a complete magnitude limited quiescent sample based on the rest-frame UVJ colors. When the density distribution is sampled on a scale of 2 Mpc, massive compact galaxies inhabit systematically denser regions than the parent quiescent galaxy population. Noncompact quiescent galaxies with the same stellar masses as their compact counterparts populate a similar distribution of environments. Thus the massive nature of quiescent compacts accounts for the environment dependence and appears fundamental to their history.