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arXiv · 1506.01717

Suppression of stellar tidal disruption rates by anisotropic initial conditions

Kirill Lezhnin·Eugene Vasiliev
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Abstract

We compute the rates of capture of stars by supermassive black holes, using time-dependent Fokker--Planck equation with initial conditions that have a deficit of stars on low-angular-momentum orbits. One class of initial conditions has a gap in phase space created by a binary black hole, and the other has a globally tangentially-anisotropic velocity distribution. We find that for galactic nuclei that are younger than ~0.1 relaxation times, the flux of stars into the black hole is suppressed with respect to the steady-state value. This effect may substantially reduce the number of observable tidal disruption flares in galaxies with black hole masses M>10^7 Msun.

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Kirill Lezhnin, Eugene Vasiliev. 2015-06-04. Suppression of stellar tidal disruption rates by anisotropic initial conditions. https://doi.org/10.1088/2041-8205%2F808%2F1%2Fl5

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