Ultraviolet excess of luminous quasars. II. Evidence for massive accretion disks

Journal Article · Sun May 15 04:00:00 EDT 1983 · Astrophys. J.; (United States)

DOI:https://doi.org/10.1086/160981· OSTI ID:5518425

Malkan, M A

This paper presents new infrared, optical, and ultraviolet spectra of three high-redshift quasars. They are analyzed along with three published quasar spectra. After accounting for other sources of radiation, the continua are fitted with spectra predicted for optically thick steady-state accretion disks which include the effects of general relativity. The two fitting parameters, the mass of the accreting black hole and the accretion rate, are determined by the data with a formal accuracy of 20%. The masses range from 0.2--0.5 billion M/sub sun/ for 3C 273 and PKS 0405--123 to 1--3 billion M/sub sun/ for the high-redshift quasars. The values depend on the assumed disk inclination and the angular momentum of the hole. The high luminosities of these six quasars are all within a factor of 2 of their Eddington limits, and this conclusion is not extremely sensitive to the modeling assumptions.

• Research Organization: Palomar Observatory, California Institute of Technology
• OSTI ID: 5518425
• Journal Information: Astrophys. J.; (United States), Journal Name: Astrophys. J.; (United States) Vol. 268:2; ISSN ASJOA
• 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
BLACK HOLES
COSMIC RADIO SOURCES
GALAXIES
INFRARED SPECTRA
LUMINOSITY
MASS
OPTICAL PROPERTIES
PHYSICAL PROPERTIES
QUASARS
RED SHIFT
SEYFERT GALAXIES
SPECTRA
STAR ACCRETION
STAR EVOLUTION
ULTRAVIOLET SPECTRA
VISIBLE SPECTRA