Large-scale Motions in the Perseus Galaxy Cluster
  By combining large-scale mosaics of ROSAT PSPC, XMM-Newton, and Suzaku X-ray observations, we present evidence for large-scale motions in the intracluster medium of the nearby, X-ray bright Perseus Cluster. These motions are suggested by several alternating and interleaved X-ray bright, low-temperature, low-entropy arcs located along the east-west axis, at radii ranging from ~10 kpc to over a Mpc. Thermodynamic features qualitatively similar to these have previously been observed in the centers of cool core clusters, and were successfully modeled as a consequence of the gas sloshing/swirling motions induced by minor mergers. Our observations indicate that such sloshing/swirling can extend out to larger radii than previously thought, on scales approaching the virial radius. 
A. Simionescu, N. Werner, O. Urban, S. W. Allen, A. C. Fabian, J. S.   Sanders, A. Mantz, P. E. J. Nulsen, Y. Takei
astro-ph.CO astro-ph.HE