Particle Acceleration and Curvature TeV Emission by Rotating, Supermassive Black Holes

It is shown that particles accelerating near the event horizon of a spinning supermassive black hole that is threaded by externally supported magnetic field lines suffer severe curvature losses that limit the maximum energy they can attain to values well below that imposed by the maximum voltage drop induced by the black hole dynamo. It is further shown that the dominant fraction of the rotational energy extracted from the black hole is radiated in the TeV band. The implications for vacuum breakdown and the observational consequences are discussed.