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We investigate the role of radiative cooling within the core of large X-ray clusters using multi-phase hydrodynamics. We developed for that purpose a spherically symmetric hydrodynamical code, coupled to a fluid model that describes accurately the dark matter component. Cooling is included using a self-consistent multi-phase approach, leading to cooled gas mass deposition throughout the flow. We simulate the collapse and the subsequent evolution of a Coma-like X-ray cluster, avoiding the well-known cooling catastrophe. The total mass profile of our simulated cluster is very similar to the universal profile proposed by Navarro, Frenk & White (1995). More interestingly, we also obtain a quasi-isothermal temperature profile, which is a direct consequence of multi-phase cooling within such a potential well.
It is widely believed that structure in the Universe evolves hierarchically, as primordial density fluctuations, amplified by gravity, collapse and merge to form progressively larger systems. The structure and evolution of X-ray clusters, however, se
The current paradigm of cosmic formation and evolution of galaxy clusters foresees growth mostly through merging. Galaxies in the infall region or in the core of a cluster undergo transformations owing to different environmental stresses. For two X-r
We present a new model for the X-ray properties of the intracluster medium that explicitly includes heating of the gas by the energy released during the evolution of cluster galaxies. We calculate the evolution of clusters by combining the semi-analy
Chandra observations of the Cartwheel galaxy reveal a population of ultraluminous X-ray sources (ULXs) with lifetimes < 10^7 yr associated with a spreading wave of star formation which began some 3 x 10^8 yr ago. A population of high-mass X-ray binar
The features and make up of the population of X-ray sources in Galactic star clusters reflect the properties of the underlying stellar environment. Cluster age, mass, stellar encounter rate, binary frequency, metallicity, and maybe other properties a