Radiative cooling in SPH hydrodynamical simulations of X-ray clusters

The results from hydrodynamical TREESPH simulations of galaxy clusters are used to investigate the dependence of the final cluster X-ray properties upon the numerical resolution and the assumed star formation models for the cooled gas. When cold gas particles are allowed to convert into stars the final gas profiles show a well defined core radius and the temperature profiles are nearly flat. Final X-ray luminosities are found to be numerically stable, with uncertainties of a factor 2.