INFLUENCE OF COOLING FLOWS AND GALACTIC MOTION ON THE IRON DISTRIBUTION IN CLUSTERS OF GALAXIES

Iron abundance distributions are now known for 14 clusters of galaxies. For some clusters (e.g., Centaurus), the observed abundance increases toward the cluster center, while for the others (e.g., Coma and Hydra A) no significant inhomogeneity was observed. In order to understand this difference, we investigate the influence of cooling flow and turbulence produced by intracluster galactic motion on the iron abundance distribution by simple spherical models. We show that the cooling flow significantly flattens the iron abundance distribution produced in the early phase of a cluster if the flow velocity is sufficiently large. This effect makes the present iron distribution dependent on the flow velocity. We also show that the metal supply from a central cD galaxy is crucial in producing the observed strong central peaks of the iron abundance. Further, by applying our analysis to the above clusters, we show that the combination of these effects, contribution of the central cD galaxy, and the velocity-dependent modification of the abundance distribution by the cooling flow can qualitatively explain the observed variety at least except for clusters whose flat abundance distributions can be regarded as the result of recent merging phenomena.