Luminosity Functions of Quasars and Seyfert Galaxies

Publisher Website
Google Scholar
Abstract
The optical luminosities of extragalactic objects with broad emission lines, i.e. quasi‐stellar radio sources, radio quiet quasi‐stellar objects and Seyfert galaxies are compared. At high luminosities (M < ‐ 23) we find no difference in the form of the optical luminosity function for radio quiet and radio emitting objects; at low luminosities this function is growing steeply only for radio quiet objects, whereas for objects with higher radio indices it remains nearly constant below M = ‐ 22. This may possibly be interpreted as indicating a division between the optically bright “quasars” and the less luminous objects. The quasars with the highest radio index show only a small scatter in optical luminosities and thus yield a well defined Hubble relation.