First results on the cluster galaxy population from the Subaru Hyper
  Suprime-Cam survey. I. The role of group or cluster environment in star
  formation quenching from z = 0.2 to 1.1
  We utilize the HSC CAMIRA cluster catalog and the photo-$z$ galaxy catalog
constructed in the HSC wide field (S16A), covering $\sim$ 174 deg$^{2}$, to
study the star formation activity of galaxies in different environments over
0.2 $<$ $z$ $<$ 1.1. We probe galaxies down to $i \sim$ 26, corresponding to a
stellar mass limit of log$_{10}$(M$_*$/M$_{\odot}$) $\sim$ 8.2 and $\sim$ 8.6
for star-forming and quiescent populations, respectively, at $z$ $\sim$ 0.2.
The existence of the red sequence for low stellar mass galaxies in clusters
suggests that the environmental quenching persists to halt the star formation
in the low-mass regime. In addition, star-forming galaxies in groups or
clusters are systematically biased toward lower values of specific star
formation rate by 0.1 -- 0.3 dex with respect to those in the field and the
offsets shows no strong redshift evolution over our redshift range, implying a
universal slow quenching mechanism acting in the dense environments since $z$
$\sim$ 1.1. Moreover, the environmental quenching dominates the mass quenching
in low mass galaxies, and the quenching dominance reverses in high mass ones.
The transition mass is greater in clusters than in groups, indicating that the
environmental quenching is more effective for massive galaxies in clusters
compared to groups.
