The APM galaxy survey. IV. Redshifts of rich clusters of galaxies.

We present redshifts for a sample of 228 clusters selected from the APM Galaxy Survey, 188 of which are new redshift determinations. Redshifts are listed for 365 galaxies, and non-cluster galaxy redshifts have been rejected from this sample using a likelihood ratio test based on the projected and apparent magnitude distributions of each cluster region. We test this technique using clusters for which redshifts have been measured for more than 10 galaxies. Our redshift sample is nearly complete and has been used in previous papers to study the three-dimensional distribution of rich clusters of galaxies. 156 of the clusters in our sample are listed in the Abell catalogue or supplement, and the remainder are new cluster identifications.