Lepto-hadronic γ-ray and neutrino emission from the jet of TXS 0506+056.
Abstract (from CDS):
The observation of the IceCube-170922A event from the direction of TXS 0506+056 when it was in its enhanced γ-ray emission state offers a unique opportunity to investigate the lepto-hadronic processes in blazar jets. Here, the observed broadband emission of TXS 0506+056 is explained by boosted synchrotron/synchrotron self Compton emission from the jet, whereas the γ-ray data observed during the neutrino emission by inelastic interactions of the jet-accelerated protons in a dense gaseous target. The proton energy distribution is ∼Ep–2.50, calculated straightforwardly from the data obtained by the Fermi Large Area Telescope (Fermi-LAT) and the Major Atmospheric Gamma Imaging Cherenkov Telescopes (MAGIC); if such a distribution continues up to Ec,p = 10 PeV, the expected neutrino rate is as high as ∼0.46 events during the long active phase of the source or ∼0.15 if the activity lasts 60 days. In this interpretation, the energy content of the protons above >GeV in blazar jets can be estimated as well: the required proton injection luminosity is ≃2.0 x 1048 erg s–1 exceeding 103 times that of electrons ≃1045 erg s–1, which are in equipartition with the magnetic field. As the required parameters are physically realistic, this can be an acceptable model for an explanation of the neutrino and γ-ray emission from TXS 0506+056.