| Description |
Clusters of galaxies are the largest known gravitationally bound objects in the universe and are believed to be formed in a hierarchical sequence of structure formation. Most of the baryonic mass of the clusters resides in the very hot (kT~1-10keV) and diffuse (n~10^(-3) cm^-3) intracluster medium (ICM), which emits mainly in X-rays through Bremsstrahlung and line emission. A large fraction (~40%) of the clusters show evidence for the presence of substructures in the otherwise uniform centrally peaked X-ray surface brightness maps. Many of these clusters also show signatures of mergers. Clusters are therefore believed to be dynamically young objects. I will present a detailed imaging and spectral analysis of two such merging cluster systems viz., the bimodal cluster A3395 and the cluster pair A3532-A3530. The cluster A3395 shows three additional X-ray components besides the main NE and SW components corresponding to the already known bimodal structure. An X-ray filament is seen to be connecting the the NE component to the SW component. There is evidence for a possible heating of all the components of A3395 by the ongoing mergers. In the radio, in both the cluster systems, one of the two Brightest Cluster galaxies (BCG) is seen to host a Wide-Angle-Tailed (WAT) radio source (radio source with jets bent in C-shape) in it, which also confirms the merging environments of the clusters. Depressions in the X-ray surface brightness maps of the clusters are often found to be associated with these radio sources and are believed to be formed by the buoyantly rising radio plasma bubbles. However, while A3532 shows a large number of cavities (depressions) in its X-ray surface-brightness maps, A3395 does not show any deficit close to the location of the WAT source. I will discuss the different merging environments of these cluster systems with the help of the results obtained so far.
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