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arXiv · 1210.0752

Identifying Breaks and Curvature in the Fermi Spectra of Bright FSRQs and Constraining the Emission Region

Jonathan Harris·Michael K. Daniel·Paula M. Chadwick
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Abstract

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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Jonathan Harris, Michael K. Daniel, Paula M. Chadwick. 2012-10-02. Identifying Breaks and Curvature in the Fermi Spectra of Bright FSRQs and Constraining the Emission Region. https://doi.org/10.1063/1.4772317

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