Extended Ionized Gas Clouds in the Abell 1367 Cluster ∗

Abstract

We surveyed a central 0.6 deg 2 region of the Abell 1367 cluster for extended ionized gas clouds (EIGs) using the Subaru prime-focus camera (Suprime-Cam) with a narrowband filter that covers H α . We discovered six new EIGs in addition to five known EIGs. We also found that the H α tail from the blue infalling group is extended to about 330 kpc in projected distance, which is about twice longer than previously reported. Candidates of star-forming blobs in the tail are detected. The properties of the EIG parent galaxies in Abell 1367 basically resemble those in the Coma cluster. A noticeable difference is that there are significantly fewer detached EIGs in Abell 1367, while the fraction of blue member galaxies is higher. The results suggest a difference in the evolutionary stage of the clusters; Abell 1367 is at an earlier stage than the Coma cluster.