The 0.6 Mpc halo of the cD galaxy (MCG05 - 33 - 002) in the cluster Abell 3571 revealed by the co-addition of eight Schmidt plates

Eight IIIaJ sky-limited plates of the same field taken with the UK 1.2-m Schmidt telescope have been scanned by the APM machine and digitally co-added. The field contains the cD galaxy MCG 05-33-002, the central galaxy in the cluster A3571. A giant faint halo, of dimensions ∼600 x 200 kpc, has been found to envelop most of the cluster. It is estimated that at least a mass of 2 x 1012 solar masses is contained within the halo which would account for some of the 'missing' mass in such clusters in terms of purely luminous baryonic matter. (author)