The effect of radiative cooling on the radial density and temperature profiles of galaxy clusters

In this paper we use state-of-the-art N-body hydrodynamic simulations of a cosmological volume of side 100Mpc to produce many large clusters simultaneously in both the standard cold dark matter (SCDM) cosmology and a cosmology with a positive cosmological constant (ΛCDM). We have performed simulations of the same volume both with and without the effects of radiative cooling, but in all cases neglect the effects of star formation and feedback. We show that the effects of radiative cooling alone cannot produce a large constant density core in either the gas or the dark matter distributions. With radiative cooling clusters are on average five times less luminous than the same cluster simulated without cooling. In addition, clusters which contain a significant amount of substructure exhibit larger gas cores and, in agreement with the observations, are slightly less luminous than those without. In both the radiative and non-radiative cases the gaseous material is more extended than the dark matter out to the virial radius.