Stability of narrow emission line clouds in active galactic nuclei

Journal Article · Sun Jan 01 04:00:00 EST 1989 · Astrophys. J.; (United States)

DOI:https://doi.org/10.1086/166996· OSTI ID:6406132

Mathews, W G; Veilleux, S

The effects of the lateral flow and Rayleigh-Taylor instabilities on clouds in the narrow-line region of active galaxies are considered using cloud densities and velocities based on observations. A simplified model for the lateral flow instability governed only by overpressures is discussed. The associated radiative acceleration is considered, and parameters describing the narrow-line region and the central nonstellar continuum are presented. It is shown that many otherwise acceptable narrow-line clouds are unstable to lateral flows, particularly if their column depths are small. It is argued that the most likely narrow-line clouds have column densities of about 10 to the 23rd/sq cm and that these clouds are accelerated by winds in the intercloud medium. Arguments are made against models in which narrow-line clouds move inward. 22 references.

• Research Organization: Lick Observatory, Santa Cruz, CA (USA)
• OSTI ID: 6406132
• Journal Information: Astrophys. J.; (United States), Journal Name: Astrophys. J.; (United States) Vol. 336; ISSN ASJOA
• Country of Publication: United States
• Language: English

Related Subjects

640105* -- Astrophysics & Cosmology-- Galaxies
71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
COSMIC GASES
COSMIC RADIO SOURCES
DENSITY
EMISSION SPECTRA
FLUID FLOW
FLUID MECHANICS
FLUIDS
GALAXIES
GALAXY NUCLEI
GAS FLOW
GASES
HYDRODYNAMICS
INSTABILITY
INTERSTELLAR SPACE
MATHEMATICAL MODELS
MECHANICS
MOLECULES
PHYSICAL PROPERTIES
RAYLEIGH-TAYLOR INSTABILITY
SEYFERT GALAXIES
SPACE
SPECTRA