KYDISC: Galaxy Morphology, Quenching, and Mergers in the Cluster
  Environment
  We present the KASI-Yonsei Deep Imaging Survey of Clusters (KYDISC) targeting
14 clusters at 0.015 < z < 0.144 using the Inamori Magellan Areal Camera and
Spectrograph on the 6.5-meter Magellan Baade telescope and the MegaCam on the
3.6-meter Canada-France-Hawaii Telescope. We provide a catalog of cluster
galaxies that lists magnitudes, redshifts, morphologies, bulge-to-total ratios,
and local density. Based on the 1409 spectroscopically-confirmed cluster
galaxies brighter than -19.8 in the r-band, we study galaxy morphology, color,
and visual features generated by galaxy mergers. We see a clear trend between
morphological content and cluster velocity dispersion, which was not presented
by previous studies using local clusters. Passive spirals are preferentially
found in a highly dense region (i.e., cluster center), indicating that they
have gone through the environmental quenching. In deep images (mu_r ~ 27
mag/"^2), 20% of our sample show signatures of recent mergers, which is not
expected from theoretical predictions and a low frequency of ongoing mergers in
our sample (~ 4%). Such a high fraction of recent mergers in the cluster
environment supports a scenario that the merger events that made the features
have preceded the galaxy accretion into the cluster environment. We conclude
that mergers affect a cluster population mainly through the pre-processing on
recently accreted galaxies.
