Halo and relic sources in clusters of galaxies

New images of 7 radio halos and relics, obtained with the Very Large Array at 20 or 90 cm, are presented here. The existence of a cluster-wide radio h alo in the clusters A 665 and CL 0016+16 is confirmed. Both these clusters share the properties of the other clusters with radio halos, i. e. are lumi nous in X-rays, have high temperature, and show recent merger processes. No diffuse sources are detected in a sample of clusters showing at least a tailed radio galaxy within 300 kpc from the cluster center, indicating that the connection between tailed radio galaxies and halos is not relevant. Fo r these clusters we give limits to the surface brightness and to the angula r size of possible undetected diffuse sources. (C) 2000 Elsevier Science B. V. All rights reserved.