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Red Giant Winds as Emission Line Clouds (Broad or Narrow) in Active Galactic Nuclei

Published online by Cambridge University Press:  07 August 2017

Demosthenes Kazanas*
Affiliation:
NASA/Goddard Space Flight Center, Laboratory for High Energy Astrophysics, Geenbelt, MD 20771

Extract

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It is proposed that the clouds thought responsible for the line emission in AGN are not of uniform density but stratified. Such a stratification may be a result either of their self-gravity or of gas dynamics associated with each cloud (e.g. winds). To fix ideas we assume the latter possibility, we examine the consequences and compare with the observations and the phenomenology of emission line clouds.(For the general properties of these clouds see review by Netzer in this volume). Given the successes of the standard model the reader may wonder why is there any need for revisions. The reasons are given in detail elsewhere (see also Scoville and Norman this volume). In brief these are the drag of clouds though the confining medium, the excessive accretion rates implied by the standard model, the response of the line radiation to changes in the continuum, and the lack of a dynamical mechanism for cloud formation. Finally, in the “standard” picture the narrow line clouds are a distinct population with separate dynamics and origin.

Type
Part 5: Structure of the Central Object and NLR
Copyright
Copyright © Kluwer 1989 

References

Filippenko, A. V. and Halpern, , 1984, Ap. J., 280, 653.Google Scholar
Wamstecker, W. and Colina, L. 1986, Ap. J., 311, 617.Google Scholar
Whittle, M. 1985, M.N.R.A.S., 216, 817.CrossRefGoogle Scholar