Observations of Radio Emission from Normal Galaxies

Abstract

The results of observations of 37 normal galaxies using the 21O-ft steerable reflector of the A.N.R.A.O. at 1410 and 408 Mcls are presented. All southern galaxies brighter than tenth magnitude were studied. Twenty galaxies were detected, fourteen of which were new identifIcationis. Sc galaxies were found to have a mean radio index at 1410 Mcls of +3·3 with an r.m.s. deviation of 0·6. The ratio of optical to radio emission was signifIcantly higher for irregular and early type galaxies than for Sb and Sc galaxies_ Contrary to general belief, no constant relationship was found between the optical and radio sizes of spiral galaxies. Two discrete radio sources were detected in the Pegasus I cluster, one of which may be identified with the El galaxy, NGC 7626. The radio source found in Pegasus II coincided in position with the E3 galaxy, NGC 7501, in the cluster.