Stochastic particle acceleration in hot accretion disks

Abstract

The observed γ‐ray luminosity of ∼1048 ergs s−1 detected by EGRET during a week‐long transient from 3C 279 implies a black hole mass of at least 1010 M⊙ if the emission is isotropic and sub‐Eddington. Theoretical models suggests that the proton in the hot inner region of a two‐temperature accretion disk surrounding a rapidly rotating black hole of 1010 M⊙ contain sufficient energy to power the observed outburst. This value for the black hole mass also yields and accretion timescale for the hot region that is comparable to the observed transient timescale of 1 week. Hence the overall energetics and duration of the 3C 279 EGRET outburst can be explained if a means can be found to utilize the energy contained in the hot protons to accelerate relativistic electrons up to Lorentz factors of ∼104 before the gas crosses the event horizon.In this paper we discuss turbulent (stochastic) particle acceleration in hot disks as a possible source of GeV electrons and radiation. We present results for the energetic part...