Photohadronic origin of multi-TeV flarings from high energy peaked blazars

VHE flaring events have been observed to be a predominant event of the activity of high energy peaked blazars (HBLs). These flaring epochs involve energies in the GeV-TeV range and different timescales, yet their emission mechanisms are still not well understood. The emitted γ-rays en route to Earth undergo energy-dependent attenuation due to the interaction with extra galactic background light. Considering the photohadronic model where Fermi-accelerated protons interact with the seed photons in a double jet scenario, we derived a simple relation for the observed multi-TeV γ-ray flux as a function of two free parameters. We studied 42 flaring epochs from 23 HBLs and found that our model accurately describes the observed VHE spectra for all these cases, supporting the photohadronic origin of multi-TeV γ-rays. Moreover, this model allows to constrain the power spectrum of seed photons during the flaring period even ifthe simultaneous spectral energy distribution is unknown. We also used this model to set stringent bounds on the red shifts of two HBLs with unknown distances but observed multi-TeV spectra.