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Though feedback from central active galactic nuclei provides an attractive solution to the problem of overcooling in galaxy cluster cores, another possible source of heating may come from ``sloshing of the cluster core gas initiated by mergers. We present a set of simulations of galaxy cluster mergers with subclusters in order to determine the amount of heating provided by the mechanism of sloshing, exploring a parameter space over mass ratio, impact parameter, and viscosity of the intracluster medium (ICM). Our results show that for sloshing caused by mergers with gasless subclusters cooling may be partially offset by heating from sloshing, but this mechanism is less effective if the ICM is viscous.
Diffuse radio emission has been found in many galaxy clusters, predominantly in massive systems which are in the state of merging. The radio emission can usually be classified as relic or halo emission, which are believed to be related to merger shoc
We present a detailed analysis from new multi-wavelength observations of the exceptional galaxy cluster ACT-CL J0102-4915 El Gordo, likely the most massive, hottest, most X-ray luminous and brightest Sunyaev-Zeldovich (SZ) effect cluster known at z>0
Primordial black holes (PBHs) from the early Universe constitute a viable dark matter (DM) candidate and can span many orders of magnitude in mass. Light PBHs with masses around $10^{15}$ g contribute to DM and will efficiently evaporate through Hawk
The sloshing of the cold gas in the cores of relaxed clusters of galaxies is a widespread phenomenon, evidenced by the presence of spiral-shaped cold fronts in X-ray observations of these systems. In simulations, these flows of cold gas readily form
We present a detailed analysis of the velocity structure of the Virgo cluster using {it XMM-Newton} observations. Using a novel technique which uses uses the Cu K$alpha$ instrumental line to calibrate the EPIC-pn energy scale, we are able to obtain v