EDP Sciences Journals List
Advanced Search
Free access article

Issue A&A
Volume 387, Number 3, June I 2002
Page(s) 804 - 817
Section Extragalactic astronomy
DOI http://dx.doi.org/10.1051/0004-6361:20020255



A&A 387, 804-817 (2002)
DOI: 10.1051/0004-6361:20020255

The role of the central stellar cluster in active galactic nuclei

I. Semi-analytical model
E. Y. Vilkoviskij1, 2 and B. Czerny3

1  Fesenkov Astrophysical Institute, Observatory, 480020 Almaty, Kazakstan
    e-mail: vilk@afi.south-capital.kz
2  Isaac Newton Institute of Chile, the Kazakhstan branch
3  Copernicus Astronomical Center, Bartycka 18, 00-716 Warsaw, Poland

(Received 29 August 2001 / Accepted 18 February 2002)

Abstract
The subject of the paper is the role of the massive stellar cluster in the activity phenomenon and in the structure of active galactic nuclei. We introduce a simple model of stellar dynamics in the internal part of the cluster, which allows us to include both the star-disk and the star-star interactions. It is shown that the properties of the distribution of stars in the vicinity of the black hole are determined both by the interaction of the stars with the accretion disk and by the pair gravitational and contact interaction between the stars. We calculate the distribution of stars in the central parts of the cluster and we discuss possible effects of stellar mass-loss due to the star-disk interaction. Finally, we study the implications of the central cluster for active galactic nuclei activity. We model the broad line region assuming that the gaseous wakes, following stars after each disk crossing, play the role of the broad line region clouds, and we calculate the corresponding line profiles. We also analyze the contribution of star-star and star-disk collisions to active galactic nuclei variability.


Key words: galaxies: active -- galaxies: Seyfert -- stellar dynamics -- ultraviolet: galaxies -- X-rays: galaxies

Offprint request: B. Czerny, bcz@camk.edu.pl

SIMBAD Objects



© ESO 2002


What is OpenURL?

The OpenURL standard is a protocol for transmission of metadata describing the resource that you wish to access. An OpenURL link contains article metadata and directs it to the OpenURL server of your choice. The OpenURL server can provide access to the resource and also offer complementary services (specific search engine, export of references...). The OpenURL link can be generated by different means.
  • If your librarian has set up your subscription with an OpenURL resolver, OpenURL links appear automatically on the abstract pages.
  • You can define your own OpenURL resolver with your EDPS Account. In this case your choice will be given priority over that of your library.
  • You can use an add-on for your browser (Firefox or I.E.) to display OpenURL links on a page (see http://www.openly.com/openurlref/). You should disable this module if you wish to use the OpenURL server that you or your library have defined.