The effect of anisotropic emission from thick accretion disks on the luminosity functions of active galactic nuclei

Journal Article · Mon Apr 01 00:00:00 EST 1991 · Astrophysical Journal; (United States)

DOI:https://doi.org/10.1086/169914· OSTI ID:5587090

Urry, C M; Marziani, P; Calvani, M ^[1]

---

1. Space Telescope Science Institute, Baltimore, MD (USA) Scuola Internazionale Superiore di Studi Avanzati, Trieste (Italy)

High-luminosity active galactic nuclei (AGNs) powered by accretion onto a massive black hole (or other compact object) may have bolometric luminosities dominated by thermal emission from a geometrically thick accretion disk. Radiation from these disks is strongly anisotropic, which has important consequences for the observed luminosity distribution, and therefore for systematic biases in flux-limited samples. The effect of anisotropic emission from an ensemble of AGNs with random oriented thick disks radiating at or near the Eddington limit is calculated. Because of their higher luminosities, it is predicted face-on disks should constitute an increasing fraction of observed high-redshift, high-luminosity AGNs. Comparison of the results with observed quasar luminosity functions suggests a narrow mass distribution with an upper limit of about a billion solar masses for high-redshift quasars. 25 refs.

• OSTI ID: 5587090
• Journal Information: Astrophysical Journal; (United States), Vol. 371; ISSN 0004-637X
• Country of Publication: United States
• Language: English

Related Subjects

71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
GALAXY NUCLEI
LUMINOSITY
ACCRETION DISKS
ANISOTROPY
BLACK HOLES
BRIGHTNESS
COMPARATIVE EVALUATIONS
MASS DISTRIBUTION
SEYFERT GALAXIES
STAR ACCRETION
DISTRIBUTION
GALAXIES
OPTICAL PROPERTIES
PHYSICAL PROPERTIES
SPATIAL DISTRIBUTION
STAR EVOLUTION
640105* - Astrophysics & Cosmology- Galaxies