Parameters of active galaxy nuclei, and the approach to critical luminosity

Journal Article · Thu Mar 01 04:00:00 EST 1984 · Sov. Astron. (Engl. Transl.); (United States)

OSTI ID:6583897

Dibai, E A

Although active nuclei of galaxies can be described by diversified empirical parameters, they all depend on a single dimensionless quantity: the ratio of the observed nucleus luminosity L to the critical Eddington luminosity L/sub E/dd for the corresponding mass. Parameters are analyzed for a sample of roughly-equal100 Seyfert 1, 2 galaxies and nearby quasars. As L ..-->.. L/sub E/dd: a) the proportion of active-nucleus radiation increases relative to the underlying background of the parent galaxy; b) beginning at some critical velocity a gas outflow develops, producing the broad permitted-line emission wings; c) the nucleus continuum ''hardens.'' Quasars and Seyfert 1 nuclei have near-critical luminosities, whereas Seyfert 2 nuclei have L<

• Research Organization: Shternberg Astronomical Institute, Moscow
• OSTI ID: 6583897
• Journal Information: Sov. Astron. (Engl. Transl.); (United States), Journal Name: Sov. Astron. (Engl. Transl.); (United States) Vol. 28:2; ISSN SAAJA
• Country of Publication: United States
• Language: English

Related Subjects

640103* -- Astrophysics &amp; Cosmology-- Quasi-Stellar
Radio
&amp; X-Ray Sources-- (-1987)
640105 -- Astrophysics &amp; Cosmology-- Galaxies
71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
COSMIC RADIO SOURCES
GALAXIES
GALAXY NUCLEI
LUMINOSITY
MASS
OPTICAL PROPERTIES
PHYSICAL PROPERTIES
QUASARS
SEYFERT GALAXIES