Halo Occupation Distribution of Massive Galaxies since z = 1
  We present a clustering analysis of ~60,000 massive (stellar mass Mstar >
10^{11} Msun) galaxies out to z = 1 drawn from 55.2 deg2 of the UKIRT Infrared
Deep Sky Survey (UKIDSS) and the Sloan Digital Sky Survey (SDSS) II Supernova
Survey. Strong clustering is detected for all the subsamples of massive
galaxies characterized by different stellar masses (Mstar = 10^{11.0-11.5}
Msun, 10^{11.5-12.0} Msun) or rest-frame colors (blue: U - V < 1.0, red: U - V
> 1.0). We find that more mature (more massive or redder) galaxies are more
clustered, which implies that more mature galaxies have started stellar-mass
assembly earlier within the highly-biased region where the structure formation
has also started earlier. By means of halo occupation distribution (HOD) models
fitted to the observed angular correlation function, we infer the properties of
the underlying host dark halos. We find that the estimated bias factors and
host halo masses are systematically larger for galaxies with larger stellar
masses, which is consistent with the general agreement that the capability of
hosting massive galaxies depends strongly on halo mass. The estimated effective
halo masses are ~10^{14} Msun, which gives the stellar-mass to halo-mass ratios
of ~0.003. The observed evolution of bias factors indicates rapid evolution of
spatial distributions of cold dark matter relative to those traced by the
massive galaxies, while the transition of host halo masses might imply that the
fractional mass growth rate of halos is less than those of stellar systems. The
inferred halo masses and high fractions of central galaxies indicate that the
massive galaxies in the current sample are possibly equivalent to central
galaxies of galaxy clusters.
