Photohadronic scenario in interpreting the February-March 2014 flare of 1ES 1011+496

TL;DR

This paper explains the complex spectrum of a 2014 gamma-ray flare from 1ES 1011+496 using a photohadronic model combined with an EBL template, highlighting spectral shape changes linked to optical depth variations.

Contribution

The study applies a photohadronic model with a specific EBL template to interpret the flare spectrum, introducing the spectral index as the key free parameter and explaining spectral features.

Findings

The spectrum fits well with the photohadronic model and EBL template.

The spectral shape change is due to optical depth behavior above 600 GeV.

The spectral index $oldsymbol{ extit{ extalpha}}$ is the only free parameter.

Abstract

The extraordinary multi-TeV flare from 1ES 1011 +496 during February-March 2014 was observed by MAGIC telescopes for 17 nights and the average spectrum of the whole period has a non-trivial shape. We have used the photohadronic model and a template EBL model to explain the average spectrum which fits well to the flare data. The spectral index $\alpha$ is the only free parameter in our model. We have also shown that the non-trivial nature of the spectrum is due to the change in the behavior of the optical depth above $\sim 600$ GeV $\gamma$-ray energy accompanied with the high SSC flux.