The Cosmological Evolution of Quasars
- 1 March 1978
- journal article
- Published by IOP Publishing in Physica Scripta
- Vol. 17 (3) , 329-332
- https://doi.org/10.1088/0031-8949/17/3/031
Abstract
There is compelling evidence that quasars, both optically selected and radio selected ones, exhibit strong cosmological evolution. If the space density is an exponential of cosmic time, then the characteristic time of decline is one-tenth of the age of the Universe. Quasars with flat radio spectrum appear to show less cosmological evolution.Keywords
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