ROSAT HRI observations of four high-redshift clusters of galaxies

ROSAT HRI data for four rich clusters of galaxies at redshifts of ∼0.5 that contain radio sources are presented. One of the clusters, 53W080, is detected at the 5.2 σ level; 53W076 is marginally detected at the 2.7 σ level; and the other two clusters, 1130 + 34 and 1245 + 34, have interestingly low upper bounds on their X-ray luminosities. The X-ray emission is unresolved and could originate from either the hot intracluster medium or the radio source. A comparison of the expected and observed X-ray luminosity of 53W080 suggests that the X-ray emission from this source is produced by the active galactic nucleus (AGN).