Observations of X-ray clusters of galaxies at 102.5 MHz

Observations with the BSA FIAN radio telescope at 102.5 MHz of 24 Ariel V X-ray sources identified with clusters of galaxies are presented. The measured flux densities have been used to determine the radio powers and spectral indices of these objects. Comparison of these results with data obtained for other nearby clusters at the same frequency shows that X-ray clusters have on average higher radio powers and a lower dispersion in this parameter. There is weak evidence for a correlation between spectral index and X-ray luminosity, but there is no correlation between spectral index and radio power nor between X-ray luminosity and radio power. A comparison of the present results from 15 clusters common to the survey of 2A X-ray sources made by Slee and Quinn suggests that five of these clusters contain radio sources with angular diameters > 8 arcmin. The radio emission from clusters has a significantly steeper spectrum than that of the majority of nearby radio galaxies. We suggest that these results can be explained by the effects of hot intracluster gas on radio galaxy evolution in X-ray clusters. (author)