X-ray constraints on the dark matter profile of a very relaxed cluster   of galaxies
  We have analyzed an XMM-Newton observation of the cluster Abell 2589. Apart from a low-level asymmetry in the central region, the cluster appears very relaxed and does not show presence of a central AGN. We derived constraints for the radial temperature, density and, assuming hydrostatic equilibrium, mass profiles. We find that the best fit to the dark matter profile is given by the Sersic-like profile proposed by Navarro et al. (2004). The NFW model does not provide a good fit. We also tested whether the central stellar component could affect the profile through the adiabatic contraction model but were unable to distinguish it from a simple "dark matter + stars" modeling. 
L. Zappacosta (1), D.A. Buote (1), F. Gastaldello (1), P.J. Humphrey   (1), J. Bullock (1), F. Brighenti (2 and 3), W. Mathe...