The UVX quasar optical luminosity function and its evolution
نویسندگان
چکیده
The recently-finished Edinburgh UVX quasar survey at B < 18 is used together with other complete samples to estimate the shape and evolution of the optical luminosity function in the redshift range 0.3 < z < 2.2. There is a significantly higher space density of quasars at high luminosity and low redshift than previously found in the PG sample of Schmidt & Green (1983), with the result that the shape of the luminosity function at low redshifts (z < 1) is seen to be consistent with a single power-law. At higher redshifts the slope of the power-law at high luminosities appears to steepen significantly. There does not appear to be any consistent break feature which could be used as a tracer of luminosity evolution in the population.
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