Chaotic Loss Cones, Black Hole Fueling and the M-Sigma Relation

David Merritt; M. Y. Poon

doi:10.1086/382497

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arXiv · astro-ph/0302296

Chaotic Loss Cones, Black Hole Fueling and the M-Sigma Relation

David Merritt·M. Y. Poon

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Abstract

In classical loss cone theory, stars are supplied to a central black hole via gravitational scattering onto low angular momentum orbits. Higher feeding rates are possible if the gravitational potential near the black hole is non-axisymmetric and the orbits are chaotic. Motivated by recently published, self-consistent models, we evaluate rates of stellar capture and disruption in triaxial nuclei. Rates are found to substantially exceed those in collisionally-resupplied loss cones, as long as an appreciable fraction of the orbits are centrophilic. The mass captured by a black hole after a given time in a steep nucleus scales as the fifth power of the velocity dispersion, and the accumulated mass in 10^10 yr is of the correct order to reproduce the M-sigma relation. Triaxiality can solve the "final parsec problem" of decaying black hole binaries by increasing the flux of stars into the binary's loss cone.

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David Merritt, M. Y. Poon. 2003-08-13. Chaotic Loss Cones, Black Hole Fueling and the M-Sigma Relation. https://doi.org/10.1086/382497

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