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The large-scale distribution of quasars identified with strong radio sources at 5 GHz
Authors:P Shastri  Gopal-Krishna
Institution:(1) Radio Astronomy Centre, Tata Institute of Fundamental Research, PO Box 1234, 560012 Bangalore
Abstract:The large-scale angular distribution of quasars from a complete sample of extragalactic radio sources is examined at different redshifts. The sample contains 264 quasars which have been found so far among the complete sample of 518 radio sources stronger than. 1 Jy at 5 GHz. Of these, 19 quasars have redshift z > 2. Dividing the entire sky into three separate declination zones of equal area, the counts of quasars seem to indicate a deficit of high redshift quasars in the northernmost declination zone. On the other hand, the Iow-redshift quasars (z < 1) appear fairly uniformly distributed. We discuss some possible selection effects that might have led to the apparent anomaly at high redshifts and estimate the expected number of high-redshift quasars amongst the radio sources in the sample for which redshifts are presently not available.
Keywords:quasars  radio-bright  quasars  distribution of
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