Multi-TeV flaring from high energy blazars: An evidence of the photohadronic process

Sarira Sahu; Carlos E. Lopez Fortin; Shigehiro Nagataki

doi:10.3847/2041-8213/ab43c7

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arXiv · 1909.10634

Multi-TeV flaring from high energy blazars: An evidence of the photohadronic process

Sarira Sahu·Carlos E. Lopez Fortin·Shigehiro Nagataki

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Abstract

The high energy peaked blazars are known to undergo episodes of flaring in GeV-TeV gamma-rays involving different time scales and the flaring mechanism is not well understood despite long term simultaneous multiwavelength observations. These gamma-rays en route to Earth undergo attenuation by the extra galactic background light. Using the photohadronic model, where the seed photons follow a power-law spectrum and a template extragalactic background light model, we derive a simple relation between the observed multi-TeV gamma-ray flux and the intrinsic flux with a single parameter. We study 42 flaring epochs of 23 blazars and excellent fit to most of the observed spectra are obtained, strengthening the photohadronic origin of multi-TeV gamma-rays. We can also constrain the power spectrum of the seed photons during the flaring period. The blazars of unknown redshifts, whose multi-TeV flaring spectra are known, stringent bounds on the former can be placed using the photohadronic model.

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Sarira Sahu, Carlos E. Lopez Fortin, Shigehiro Nagataki. 2019-09-23. Multi-TeV flaring from high energy blazars: An evidence of the photohadronic process. https://doi.org/10.3847/2041-8213%2Fab43c7

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