Galaxy Populations in Massive Galaxy Clusters to z=1.1: Color
  Distribution, Concentration, Halo Occupation Number and Red Sequence Fraction
  We study the galaxy populations in 74 Sunyaev Zeldovich Effect (SZE) selected
clusters from the South Pole Telescope (SPT) survey that have been imaged in
the science verification phase of the Dark Energy Survey (DES). The sample
extends up to $z\sim 1.1$ with $4 \times 10^{14} M_{\odot}\le M_{200}\le
3\times 10^{15} M_{\odot}$. Using the band containing the 4000~\AA\ break and
its redward neighbor, we study the color-magnitude distributions of cluster
galaxies to $\sim m_*+2$, finding: (1) the intrinsic rest frame $g-r$ color
width of the red sequence (RS) population is $\sim$0.03 out to $z\sim0.85$ with
a preference for an increase to $\sim0.07$ at $z=1$ and (2) the prominence of
the RS declines beyond $z\sim0.6$. The spatial distribution of cluster galaxies
is well described by the NFW profile out to $4R_{200}$ with a concentration of
$c_{\mathrm{g}} = 3.59^{+0.20}_{-0.18}$, $5.37^{+0.27}_{-0.24}$ and
$1.38^{+0.21}_{-0.19}$ for the full, the RS and the blue non-RS populations,
respectively, but with $\sim40$\% to 55\% cluster to cluster variation and no
statistically significant redshift or mass trends. The number of galaxies
within the virial region $N_{200}$ exhibits a mass trend indicating that the
number of galaxies per unit total mass is lower in the most massive clusters,
and shows no significant redshift trend. The red sequence (RS) fraction within
$R_{200}$ is $(68\pm3)$\% at $z=0.46$, varies from $\sim$55\% at $z=1$ to
$\sim$80\% at $z=0.1$, and exhibits intrinsic variation among clusters of
$\sim14$\%. We discuss a model that suggests the observed redshift trend in RS
fraction favors a transformation timescale for infalling field galaxies to
become RS galaxies of 2 to 3~Gyr.
