Positions and some Identifications for 111 Sources of about 1 Flux Unit at 408 MHz

doi:10.1071/PH720559

Positions and some Identifications for 111 Sources of about 1 Flux Unit at 408 MHz

DG Hoskins, HS Murdoch, C Hazard and DL Jauncey

Australian Journal of Physics 25(5) 559 - 580
Published: 1972

Abstract

Radio positions with an accuracy of ~ 5 sec arc have been measured for a sample of 111 sources that have flux densities in the range 0·6 to 5·5 f.u. at 408 MHz but which are not listed in the 4C catalogue. An investigation of the random background rates for both galaxies and BSO's shows that the expected chance identification rate is small for galaxies brighter than 19m and for BSO's to the plate limit. A comparison of optical and radio positions shows that radio?optical separations of up to 15 sec arc are common for galaxies of 18m or brighter, but rare for BSO's. The identification content, corrected for chance associations, is 16% BSO's and 20% galaxies.