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The Fate of Non-Radiative Magnetized Accretion Flows: Magnetically-Frustrated Convection

Ue-Li Pen·Christopher D. Matzner·Shingkwong Wong
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Abstract

We present a scenario for non-radiative accretion onto the supermassive black hole at the galactic center. Conducting MHD simulations with 1400^3 grid zones that break the axial and reflection symmetries of earlier investigations and extend inward from the Bondi radius, we find a quasi-hydrostatic radial density profile rho propto r^{-0.72} with superadiabatic gradient corresponding to an n~0.72 polytrope. Buoyancy generated by magnetic dissipation is resisted by the same fields so effectively that energy is advected inward: a state of magnetically-frustrated convection. This scenario is consistent with observational constraints on energetics andouter boundary conditions.

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Ue-Li Pen, Christopher D. Matzner, Shingkwong Wong. 2003-07-13. The Fate of Non-Radiative Magnetized Accretion Flows: Magnetically-Frustrated Convection. https://doi.org/10.1086/379339

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