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تسجيل مستخدم جديدAbell 1451 and 1RXS J131423.6-251521: a multi-wavelength study of two dynamically perturbed clusters of galaxies
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I.Valtchanov
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We present results from optical, X-ray and radio observations of two X-ray bright (L_X ~ 10^{45} erg/s) galaxy clusters. A1451 is at redshift z=0.1989 and has line-of-sight velocity dispersion sigma_v = 1330 km/s as measured from 57 cluster galaxies. It has regular X-ray emission without signs of substructure, a Gaussian velocity distribution, lack of a cooling flow region and significant deviations from the observed scaling laws between luminosity, temperature and velocity dispersion, indicating a possible merging shock. There is only one spectroscopically confirmed cluster radio galaxy, which is close to the X-ray peak. 1RXS J131423.6-251521 has z=0.2474 and sigma_v = 1100 km/s from 37 galaxies. There are two distinct galaxy groups with a projected separation of ~700 kpc. The velocity histogram is bi-modal with a redshift-space separation of ~1700 km/s, and the X-ray emission is double peaked. Although there are no spectroscopically confirmed cluster radio galaxies, we have identified a plausible relic source candidate.
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