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Hadronic gamma-ray emission models

Karl Mannheim
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Abstract

The discovery of rapid and simultaneous TeV/optical (UV, X-ray) variability provides strong evidence against the interaction between a thermal radiation field produced by an accretion flow and relativistic electrons in a jet as the origin of the gamma-rays in BL Lacertae objects. Synchrotron-self-Compton scattering (SSC) or proton-initiated cascades (PIC) remain viable mechanisms. The mechanisms predict very different magnetic field strengths and upper cut-off energies in the gamma-ray sources, i.e. the field strengths in SSC models are more than two orders of magnitude lower than in PIC models and the PIC spectra do not cut-off at TeV.

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Karl Mannheim. 1996-12-06. Hadronic gamma-ray emission models. https://arxiv.org/abs/astro-ph/9612066

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