Simulations of the effects of stripping and accretion on galaxy haloes in clusters

We present results from a series of hydrodynamic simulations investigating ram pressure stripping of galactic haloes as the host galaxy falls radially into a cluster. We perform a parameter study comprising variations in initial gas content, gas injection rate (via stellar mass loss processes), galaxy mass and amplitude of infall. From the simulation results we track variations in both physical quantities (e.g. gas mass) and directly observable quantities (e.g. X-ray luminosities). The luminosity of the X-ray halo of the galaxy is found to compare favourably with the observationally determined correlation with the optical blue-band luminosity (L (X) : L-B ) relation. Factors affecting the X-ray luminosity are explored and it is found that the gas injection rate is a dominant factor in determining the integrated luminosity. Observational properties of the material stripped from the galaxy, which forms an X-ray wake, are investigated and it is found that wakes are most visible around galaxies with a substantial initial gas content, during their first passage though the cluster. We define a statistical skewness measure that may be used to determine the direction of motion of a galaxy using X-ray observations. Structures formed in these simulations are similar to the cold fronts seen in observations of cluster mergers where a sharp increase in surface brightness is accompanied by a transition to a cooler region.