HAL will be down for maintenance from Friday, June 10 at 4pm through Monday, June 13 at 9am. More information
Skip to Main content Skip to Navigation
Preprints, Working Papers, ...

Electron-proton co-acceleration on relativistic shocks in extreme-TeV blazars

Abstract : The multi-wavelength emission from a newly identified population of `extreme-TeV' blazars, with Compton peak frequencies around 1 TeV, is difficult to interpret with standard one-zone emission models. Large values of the minimum electron Lorentz factor and quite low magnetisation values seem to be required. We propose a scenario where protons and electrons are co-accelerated on internal or recollimation shocks inside the relativistic jet. In this situation, energy is transferred from the protons to the electrons in the shock transition layer, leading naturally to a high minimum Lorentz factor for the latter. A low magnetisation favours the acceleration of particles in relativistic shocks. The shock co-acceleration scenario provides additional constraints on the set of parameters of a standard one-zone lepto-hadronic emission model, reducing its degeneracy. Values of the magnetic field strength of a few mG and minimum electron Lorentz factors of 10^3 to 10^4, required to provide a satisfactory description of the observed spectral energy distributions of extreme blazars, result here from first principles. While acceleration on a single standing shock is sufficient to reproduce the emission of most of the extreme-TeV sources we have examined, re-acceleration on a second shock appears needed for those objects with the hardest gamma-ray spectra. Emission from the accelerated proton population, with the same number density as the electrons but in a lower range of Lorentz factors, is strongly suppressed. Satisfactory self-consistent representations were found for the most prominent representatives of this new blazar class.
Document type :
Preprints, Working Papers, ...
Complete list of metadata

Contributor : Martin Lemoine Connect in order to contact the contributor
Submitted on : Monday, October 11, 2021 - 12:16:32 PM
Last modification on : Tuesday, January 4, 2022 - 6:29:13 AM

Links full text


  • HAL Id : hal-03373084, version 1
  • ARXIV : 2108.12271


Martin Lemoine, Andreas Zech. Electron-proton co-acceleration on relativistic shocks in extreme-TeV blazars. 2021. ⟨hal-03373084⟩



Record views