Suzaku Observation of Nearby On-Going Merger Cluster Abell 3627

Abstract

We present the results of the Suzaku observation of a nearby (z = 0.016), on-going merger cluster, Abell 3627. The overall temperature of the ICM is around 7 keV, and we found a cool region with kT ∼ 4-5 keV at the position corresponding to the brightness excess from a spherically symmetrical β-model found by ROSAT. This structure seems to be a subcluster colliding into the main body. In the temperature and density profiles, no apparent jump associated with a shock is confirmed at the colliding position; therefore, the velocity of the subcluster seems to be subsonic. On the other hand, the line-of-sight velocity of the subcluster is strictly restricted to be less than 800 km s^-1 using the Doppler shift of the Fe-K lines. Moreover, our ICM temperature map also suggests the possibility of another merging subcluster in the north-west region. A 3627 is now in the process of an aggressive cluster merger, associated with the formation of a large-scale structure.