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Radiative Efficiency of Collisionless Accretion

Andrei V. Gruzinov
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Abstract

Radiative efficiency of a slowly accreting black hole is estimated using a two-temperature model of accretion. The radiative efficiency depends on the magnetic field strength near the Schwarzschild radius. For weak magnetic fields (magnetic energy=equipartition/1000), the low efficiency 0.0001 assumed in some theoretical models might be achieved. For stronger fields, a significant fraction of viscous heat is dissipated by electrons and radiated away resulting in a larger efficiency. At equipartition magnetic fields, we estimate efficiency = of order 10%.

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Andrei V. Gruzinov. 1997-10-13. Radiative Efficiency of Collisionless Accretion. https://doi.org/10.1086/305845

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