Identification of Abell Cluster 754 with the X-ray source 3U0901–09 by Ariel V

Abstract

THE faint, high galactic latitude X-ray source 3U0901–09 (ref. 1) has been previously associated², on positional grounds, with the rich cluster of galaxies, Abell 754 (distance class 3, richness class 2)³. Since the Uhuru 90%-confidence positional error box for 3U0901–09 is relatively large, having an area of 2.6 degree², it is worthwhile, in view of current theoretical interest in X-ray emission from clusters of galaxies (see, for example, ref. 8), to reduce the positional uncertainty and thus confirm or reject the proposed identification with A754.