The origin of wide-angle tailed radio galaxies

To investigate the origins of wide-angle tailed radio sources (WATs), we ha ve compiled a sample of these systems in Abell clusters for which X-ray dat a exist. Contrary to conventional wisdom, the WATs are found to be signific antly displaced from the X-ray centroids of their host clusters. The bends in the radio jets of WATs are found to be oriented preferentially such that they point directly away from or toward the cluster centre, with more of t he former than the latter. If this morphology is attributed to ram pressure , then the WATs are on primarily radial orbits, with more approaching the X -ray centroid than receding. There is also some evidence that the incoming WATs are on average further from the X-ray centroid than the outgoing ones. All of these observations strongly support a scenario in which WATs are cr eated in cluster mergers.