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

Abstract

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.

Authors:
; ;  [1]
  1. Space Telescope Science Institute, Baltimore, MD (USA) Scuola Internazionale Superiore di Studi Avanzati, Trieste (Italy)
Publication Date:
OSTI Identifier:
5587090
Resource Type:
Journal Article
Journal Name:
Astrophysical Journal; (United States)
Additional Journal Information:
Journal Volume: 371; Journal ID: ISSN 0004-637X
Country of Publication:
United States
Language:
English
Subject:
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

Citation Formats

Urry, C M, Marziani, P, and Calvani, M. The effect of anisotropic emission from thick accretion disks on the luminosity functions of active galactic nuclei. United States: N. p., 1991. Web. doi:10.1086/169914.
Urry, C M, Marziani, P, & Calvani, M. The effect of anisotropic emission from thick accretion disks on the luminosity functions of active galactic nuclei. United States. https://doi.org/10.1086/169914
Urry, C M, Marziani, P, and Calvani, M. 1991. "The effect of anisotropic emission from thick accretion disks on the luminosity functions of active galactic nuclei". United States. https://doi.org/10.1086/169914.
@article{osti_5587090,
title = {The effect of anisotropic emission from thick accretion disks on the luminosity functions of active galactic nuclei},
author = {Urry, C M and Marziani, P and Calvani, M},
abstractNote = {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.},
doi = {10.1086/169914},
url = {https://www.osti.gov/biblio/5587090}, journal = {Astrophysical Journal; (United States)},
issn = {0004-637X},
number = ,
volume = 371,
place = {United States},
year = {Mon Apr 01 00:00:00 EST 1991},
month = {Mon Apr 01 00:00:00 EST 1991}
}