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We present results from recent Suzaku and Chandra X-ray, and MMT optical observations of the strongly merging double cluster A1750 out to its virial radius, both along and perpendicular to a putative large-scale structure filament. Some previous studies of individual clusters have found evidence for ICM entropy profiles that flatten at large cluster radii, as compared with the self-similar prediction based on purely gravitational models of hierarchical cluster formation, and gas fractions that rise above the mean cosmic value. Weakening accretion shocks and the presence of unresolved cool gas clumps, both of which are expected to correlate with large scale structure filaments, have been invoked to explain these results. In the outskirts of A1750, we find entropy profiles that are consistent with self-similar expectations, and gas fractions that are consistent with the mean cosmic value, both along and perpendicular to the putative large scale filament. Thus, we find no evidence for gas clumping in the outskirts of A1750, in either direction. This may indicate that gas clumping is less common in lower temperature (kT~4keV), less massive systems, consistent with some (but not all) previous studies of low mass clusters and groups. Cluster mass may therefore play a more important role in gas clumping than dynamical state. Finally, we find evidence for diffuse, cool (<1 keV) gas at large cluster radii (R200) along the filament, which is consistent with the expected properties of the denser, hotter phase of the WHIM.
We present results from Suzaku Key Project observations of the Virgo Cluster, the nearest galaxy cluster to us, mapping its X-ray properties along four long `arms extending beyond the virial radius. The entropy profiles along all four azimuths increa
We present results from Chandra and XMM-Newton observations of Abell 98 (A98), a galaxy cluster with three major components: a relatively bright subcluster to the north (A98N), a disturbed subcluster to the south (A98S), and a fainter subcluster to t
Diffuse radio emission associated with the intra-cluster medium (ICM) is observed in a number of merging galaxy clusters. It is currently believed that in mergers a fraction of the kinetic energy is channeled into non-thermal components, such as turb
Structure formation in the current Universe operates through the accretion of group-scale systems onto massive clusters. The detection and study of such accreting systems is crucial to understand the build-up of the most massive virialized structures
The observational features of the massive galaxy cluster El Gordo (ACT-CL J0102-4915), such as the X-ray emission, the Sunyaev-Zeldovich (SZ) effect, and the surface mass density distribution, indicate that they are caused by an exceptional ongoing h