HARD GAMMA-RAY SOURCE SPECTRA IN TeV BLAZARS
EVA LEFAMax-Planck-Institut für Kernphysik, P.O. Box 103980, 69029 Heidelberg, Germany Landessternwarte, Königstuhl 12, 69117 Heidelberg, Germany FRANK M. RIEGERMax-Planck-Institut für Kernphysik, P.O. Box 103980, 69029 Heidelberg, Germany European Associated Laboratory for Gamma-Ray Astronomy, jointly supported by CNRS and MPG, Germany FELIX A. AHARONIANMax-Planck-Institut für Kernphysik, P.O. Box 103980, 69029 Heidelberg, Germany Dublin Institute for Advanced Studies, 31 Fitzwilliam Place, Dublin 2, Ireland
The problem of the hard (intrinsic) γ-ray source spectra in TeV blazars is examined. We show that relativistic Maxwell-like particle distributions provide a suitable interpretation for the inferred hard, very high energy (VHE) photon spectra. We discuss the potential of these distributions to produce broader and softer spectra if multiple zones contribute to the observed emission. We show that the dominance of one component could lead to a VHE flaring state with hard spectral features, like the one observed for Mkn 501 in July 2009.
Keywords: Blazars; Gamma-ray emission; Stochastic acceleration; Maxwellian distribution