Are wide-angle radio-tail QSOs members of clusters of galaxies ? I. VLA maps at 20 CM of 117 radio quasars.
The possibility that quasars may occur as members of clusters or groups of galaxies has important implications for the interpretation of the quasar phenomenon and for studies of galaxy and cluster evolution. Available data support the hypothesis that the distorted radio morphologies of both 1400+162 and 3C275.1 are due to interaction with dense intracluster media. In connection with these results, the present investigation is concerned with a VLA snapshot survey of 3C, 4C, and Molonglo QSOs in order to identify objects showing distortions in their radio maps. To ensure a high percentage of resolved sources, observations were primarily conducted of objects in several low-frequency surveys, taking into account the 3C, 3CR, 4C, and two Molonglo surveys. Observations of over 120 quasars were obtained during VLA runs on November 23, 1980, and April 23, 1981. It was found that a significant portion of radio QSOs are distorted or 'bent' triple sources. On the other hand, the distortions observed may not all be due to interactions with external media.