Enhancing the rate of tidal disruptions of stars by a self-gravitating disc around a massive central black hole

We further study the idea that a self-gravitating accretion disc around a supermassive black hole can increase the rate of gradual orbital decay of stellar trajectories (and hence tidal disruption events) by setting some stars on eccentric trajectories. Cooperation between the gravitational field of...

Full description

Bibliographic Details
Main Authors: Šubr L., Karas V.
Format: Article
Language:English
Published: EDP Sciences 2012-12-01
Series:EPJ Web of Conferences
Online Access:http://dx.doi.org/10.1051/epjconf/20123901003
Description
Summary:We further study the idea that a self-gravitating accretion disc around a supermassive black hole can increase the rate of gradual orbital decay of stellar trajectories (and hence tidal disruption events) by setting some stars on eccentric trajectories. Cooperation between the gravitational field of the disc and the dissipative environment can provide a mechanism explaining the origin of stars that become bound tightly to the central black hole. We examine this process as a function of the black hole mass and conclude that it is most efficient for intermediate central masses of the order of ∼ 104Mʘ. Members of the cluster experience the stage of orbital decay via collisions with an accretion disc and by other dissipative processes, such as tidal effects, dynamical friction and the emission of gravitational waves. Our attention is concentrated on the region of gravitational dominance of the central body. Mutual interaction between stars and the surrounding environment establishes a non-spherical shape and anisotropy of the nuclear cluster. In some cases, the stellar sub-system acquires ring-type geometry. Stars of the nuclear cluster undergo a tidal disruption event as they plunge below the tidal radius of the supermassive black hole.
ISSN:2100-014X