Pencil-Beam Observations of Bright Galaxies at 408 MHz

Abstract

The cross-type radio telescope of the Molonglo Radio Observatory has been used to survey all galaxies of corrected total magnitude brighter than 11^m.0 which lie within its declination coverage and a further 121 galaxies brighter than photographic magnitude 12^m. 5 in a limited region of sky. In the first list 59 out of 143 galaxies were detected while in the second list 33 out of 121 galaxies were detected. For the detected galaxies there is a strong correlation between radio and optical magnitude, especially for the Morgan type f, but there are undetected galaxies whose emission is significantly lower than that predicted by the correlation. The radio emission does not depend strongly on spiral type although the proportions of detected Sb and Sc galaxies show a significant dependence on Van den Bergh type and a weaker correlation is suggested between the radio index and the Morgan galaxy type.