TeV gamma-ray fluxes from the long campaigns on Mrk 421 as constraints on the emission of TeV-PeV neutrinos and UHECRs

摘要

Long TeV gamma-ray campaigns have been carried out to study the spectrum, variability and duty cycle of the BL Lac object Markarian 421. These campaigns have given some evidence of the presence of protons in the jet: (i) Its spectral energy distribution which shows two main peaks; one at low energies (similar to 1 key) and the other at high energies (hundreds of GeV), has been described by using synchrotron proton blazar model. (ii) The study of the variability at GeV gamma-rays and X-rays has indicated no significant correlation. (iii) TeV gamma-ray detections without activity in X-rays, called "orphan flares" have been observed in this object.