  The correlation between active galactic nuclei (AGN) and environment provides
important clues to AGN fueling and the relationship of black hole growth to
galaxy evolution. In this paper, we analyze the fraction of galaxies in
clusters hosting AGN as a function of redshift and cluster richness for X-ray
detected AGN associated with clusters of galaxies in Dark Energy Survey (DES)
Science Verification data. The present sample includes 33 AGN with L_X > 10^43
ergs s^-1 in non-central, host galaxies with luminosity greater than 0.5 L*
from a total sample of 432 clusters in the redshift range of 0.1<z<0.95.
Analysis of the present sample reveals that the AGN fraction in red-sequence
cluster members has a strong positive correlation with redshift such that the
AGN fraction increases by a factor of ~8 from low to high redshift, and the
fraction of cluster galaxies hosting AGN at high redshifts is greater than the
low-redshift fraction at 3.6 sigma. In particular, the AGN fraction increases
steeply at the highest redshifts in our sample at z>0.7. This result is in good
agreement with previous work and parallels the increase in star formation in
cluster galaxies over the same redshift range. However, the AGN fraction in
clusters is observed to have no significant correlation with cluster mass.
Future analyses with DES Year 1 through Year 3 data will be able to clarify
whether AGN activity is correlated to cluster mass and will tightly constrain
the relationship between cluster AGN populations and redshift.
