Jonathan Harris, Michael K. Daniel, Paula M. Chadwick
Deviation of the gamma-ray energy spectra of Flat Spectrum Radio Quasars (FSRQs) from a simple power law has been previously observed but the cause of this remains unidentified. If the gamma-ray emission region is close to the central black hole then absorption of gamma-rays with photons from the broad line region is predicted to produce two spectral breaks in the gamma-ray spectra at fixed energies. We examine 9 bright FSRQs for evidence of breaks and curvature. Although we confirm deviation from a simple power law, break energies are usually not where predicted by the double-absorber model. In some objects a log-parabola fit is better than a broken power law. By splitting the data into two equal time epochs we find that the spectral shape of many objects varies over time.
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http://arxiv.org/abs/1210.0752
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