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arXiv · 1308.5250

Rayleigh-Taylor instability of ionization front around black holes

KwangHo Park·Massimo Ricotti·Tiziana Di Matteo·Christopher S. Reynolds
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Abstract

We examine the role of ionizing radiation emitted from black holes (BHs) in suppressing the growth of the Rayleigh-Taylor instability (RTI) across the ionization front (I-front) that forms when the gas fueling the BH is neutral. We use radiation-hydrodynamic simulations to show that the RTI is suppressed for non-accelerating fronts on all scales resolved in our simulations. A necessary condition for the stability of the I-front is that the radius of the Strömgren sphere is larger than the Bondi radius. When this condition is violated the I-front collapses producing an accretion luminosity burst. Transient growth of the RTI occurs only during the accretion burst when the effective acceleration in the frame of reference of the I-front increases significantly due to the rapid expansion of the Strömgren sphere.

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KwangHo Park, Massimo Ricotti, Tiziana Di Matteo, Christopher S. Reynolds. 2013-11-14. Rayleigh-Taylor instability of ionization front around black holes. https://doi.org/10.1093/mnras%2Fstt2096

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