ar X iv : a st ro - p h / 99 10 26 1 v 1 1 4 O ct 1 99 9 Cluster environments around quasars at 0
نویسنده
چکیده
We have observed the galaxy environments around two complete samples of radio-loud (steep-spectrum) and radio-quiet quasars (RLQ and RQQ) at 0.5 ≤ z ≤ 0.8 that are matched in B-luminosity, and find that the environments of both quasar populations are practically indistinguishable. A few objects are found in relatively rich clusters, but on average, they seem to prefer galaxy groups or clusters of ≈ Abell class 0. By combining the RLQ sample with samples from the literature, we detect a weak, but significant, positive correlation between environmental richness and quasar radio luminosity. This may give us clues about what determines a quasar’s radio luminosity.
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