Gas deficiency in cluster galaxies - A comparison of nine clusters

Abstract

Using a combined sample of previously published results and new high-sensitivity observations, the neutral hydrogen contents of galaxies in nine clusters have been compared with those of isolated galaxies. Of the nine clusters, six show substantial H I deficiency, to varying degrees. The three clusters whose galaxies contain normal H I masses contain a higher proportion of spirals, and are not X-ray sources. In the clusters which show H I deficiency, the depletion of H I gas, exceeding factors of 10, strongly correlates with the radial distance of a galaxy from the cluster center. The data lead to the conclusion that the occurrence of H I deficiency is correlated with the presence of a hot X-ray intracluster medium, and that while perhaps not responsible for the complete mechanism of morphological segregation in clusters, an ongoing interaction process is active through the cores of X-ray clusters.