Luminosities of Seyfert galaxies and QSO's

Journal Article · Sun Aug 15 00:00:00 EDT 1976 · Astrophys. J.; (United States)

DOI:https://doi.org/10.1086/154577· OSTI ID:7350871

Weedman, D W

New observations of HB or L..cap alpha.. fluxes for 57 Seyfert galaxies and QSOs have been obtained with an intensified image-dissector scanner. Using these results with existing data, the observed or deduced H..beta.. luminosities of QSOs and class 1 Seyfert galaxies are compared. There is a continuous distribution of luminosity, assuming cosmological redshifts, such that the two types of objects overlap smoothly. Consequently, it is concluded that QSOs are distant class 1 Seyfert galaxies. If q/sub 0/=0, the range in bolometric luminosity from faintest Seyfert to brightest QSO is from 10/sup 43/ ergs s/sup -1/ to 5 x 10/sup 47/ ergs s/sup -1/, with Seyferts having a larger luminosity range than QSOs. The maximum luminosity of approx.5 x 10/sup 47/ ergs s/sup -1/ for QSOs is independent of redshift for zapproximately-greater-than0.1 and q/sub 0/=0. This therefore defines an upper luminosity limit for QSOs anywhere in the universe, or q/sub 0/ must be negative. (AIP)

• Research Organization: Dyer Observatory, Vanderbilt University
• OSTI ID: 7350871
• Journal Information: Astrophys. J.; (United States), Journal Name: Astrophys. J.; (United States) Vol. 208:1; ISSN ASJOA
• Country of Publication: United States
• Language: English

Related Subjects

640105* -- Astrophysics & Cosmology-- Galaxies
71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
BALMER LINES
COSMIC RADIO SOURCES
DOPPLER EFFECT
GALAXIES
LUMINOSITY
LYMAN LINES
OPTICAL PROPERTIES
PHYSICAL PROPERTIES
QUASARS
SEYFERT GALAXIES
SPECTRA