Enhanced activity of massive black holes by stellar capture assisted by a self-gravitating accretion disc

  title={Enhanced activity of massive black holes by stellar capture assisted by a self-gravitating accretion disc},
  author={Vladim{\'i}r Karas and Ladislav {\vS}ubr},
  journal={Astronomy and Astrophysics},
Aims. We study the probability of close encounters between stars from a nuclear cluster and a massive black hole (10 4 MM• 10 8 M� ). The gravitational field of the system is dominated by the black hole in its sphere of influence. It is further modified by the cluster mean field (a spherical term) and a gaseous disc/torus (an axially symmetric term) causing a secular evolution of stellar orbits via Kozai oscillations. Intermittent phases of high eccentricity increase the chance that stars… 

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