Stability of narrow emission line clouds in active galactic nuclei

Journal Article · Sun Jan 01 00:00:00 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), Vol. 336
• Country of Publication: United States
• Language: English

Related Subjects

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