While studies of sedimentation of metals to the center of the cluster could account, at least in part, for the excess metals, inclusion of the intracluster magnetic field gives a prohibitively long time for this process. However, cluster radial metallicity profiles show a central peak of Fe as well as other elements. The elements have an average global abundance of 0.3 Solar for rich clusters with kT ~5 keV. These elements are formed in stars and their presence in the ICM implies a connection to star formation, which takes place predominately in galaxies. The X-ray spectra from the plasma have a thermal bremsstrahlung continuum with emission lines from high ionization states of elements such as O, Fe, Si, and S. A hot (10 7−8 K), X-ray emitting intracluster medium (ICM) permeates all galaxy clusters. ![]() These large structures are typically ~3 million light years or more in radius and are roughly circular in projection. ![]() From this result, we infer that the duration of the starburst phase must be very brief so that: 1) at any time only a small fraction of the galaxies in a high ram pressure environment show this effect, and 2) most post-starburst galaxies are in an environment of low ram pressure due to their continued orbital motion in the cluster.Īn estimated 20% of all galaxies are in clusters of galaxies. However, both starburst and post-starburst galaxies are equally likely to be in a low or high ram pressure environment. This is consistent with increased star formation due to the merger. We find that post-starburst galaxies, classified as E + A, occur at a higher frequency in this merging cluster than in the Coma cluster and at a comparable rate to intermediate redshift clusters. Using archival X-ray observations and published optical data, we cross-correlate optical spectral properties (), indicative of starburst and post-starburst, respectively with ram-pressure, ρv 2, calculated from the X-ray and optical data. ![]() These phenomena should all contribute to making Abell 3266 an optimum cluster to see the global effects of RPS induced star formation. Abell 3266 (z = 0.0594) is a high mass cluster that features a high velocity dispersion, an infalling subcluster near to the line of sight, and a strong shock front. We have selected Abell 3266 to search for ram-pressure induced star formation as a global property of a merging cluster. Examples of galaxies undergoing RPS induced star formation in clusters experiencing a merger have been identified in high resolution optical images supporting the existence of a star formation phase. Some, but not all of the observations and simulations show a phase of increased star formation compared to normal spirals. Interaction between the intracluster medium and the interstellar media of galaxies via ram-pressure stripping (RPS) has ample support from both observations and simulations of galaxies in clusters.
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