Ultrafast VHE Gamma-Ray Flares of IC 310

摘要

In 2012 November MAGIC detected a bright flare from IC 310. The flare consisted of two sharp peaks with a typical duration of~ 5 min. The energy released during that event has been estimated to be at the level of 2 × 10~(44) ergs~(-1). In this work we derive an upper limit on the possible luminosity of flares generated in black hole (BH) magnetosphere, which depends very weakly on the mass of BH and is determined by disk magnetisation, viewing angle, and pair multiplicity. Since all these parameters are smaller than a unit, the luminosity 2 × 10~(43) erg s~(-1) can be taken as a strict upper limit for flare luminosity for several minutes variability time. This upper limit appears to be approximately an order of magnitude below the value measured with MAGIC. Thus, we conclude that it seems very unfeasible that the magnetospheric processes can be indeed behind the bright flaring activity recorded from IC 310.