Cosmological evolution and luminosity function of x-ray selected active galactic nuclei

Journal Article · Tue Mar 15 04:00:00 EST 1983 · Astrophys. J., Lett. Ed.; (United States)

DOI:https://doi.org/10.1086/183981· OSTI ID:6085321

Maccacaro, T; Avni, Y; Gioia, I M; Giommi, P; Griffiths, R E; Liebert, J; Stocke, J; Danziger, J

The cosmological evolution and the X-ray luminosity function of X-ray selected active galactic nuclei (AGNs) are derived and discussed.The sample used consists of 31 AGNs extracted from a fully identified sample of X-ray sources from the Einstein Observatory Medium Sensitivity Survey and is therefore exclusively defined by its X-ray properties. The distribution in space is found to be strongly nonuniform. The amount of cosmological evolution required by the X-ray data is derived in the framework of pure luminosity evolution and is found to be smaller than the amount determined from optically selected samples. The X-ray luminosity function is derived. It can be satisfactorily represented by a single power law only over a limited range of absolute luminosities. Evidence that the luminosity function flattens at low luminosity or steepens at high luminosity, or both, is presented and discussed.

• OSTI ID: 6085321
• Journal Information: Astrophys. J., Lett. Ed.; (United States), Journal Name: Astrophys. J., Lett. Ed.; (United States) Vol. 266:2; ISSN AJLEA
• Country of Publication: United States
• Language: English

Related Subjects

640103* -- Astrophysics & Cosmology-- Quasi-Stellar
Radio
& X-Ray Sources-- (-1987)
71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
COSMIC RADIO SOURCES
COSMIC RAY SOURCES
COSMIC X-RAY SOURCES
COSMOLOGY
DISTRIBUTION
GALACTIC EVOLUTION
GALAXY NUCLEI
LUMINOSITY
OPTICAL PROPERTIES
PHYSICAL PROPERTIES
QUASARS
SPATIAL DISTRIBUTION