5. Quasars and their evolution

Abstract

In the past three years several surveys of optically selected quasars have been published. The Palomar Bright Quasar Survey (Schmift & Green 1983) covers 10,714 deg to a limiting magnitude varyinq with position in the sky, with an effective limiting magnitude B = 16.16. The survey lists 114 objects of which 92 are quasars with Mg < −23. All objects have redshifts less than 2.15 as they were selected for ultraviolet excess. Marshall et al. (1983) have extended the spectroscopic coverage of objects in the Braccesi field (AB) to B = 18.25. They also report first results in the deep Braccesi field (BF) to B = 19.2. Koo (1983) reports on a photometric and spectroscopic survey of quasars to B = 22.5 (see also Koo & Kron [1982]). The present state of quasar surveys is critically discussed by Smith (1983) in a very useful review.