Hadronic gamma-ray emission from extragalactic mini radio lobes

TL;DR

This paper models gamma-ray emission from mini radio lobes in AGN, highlighting the roles of hadronic processes and secondary particle cascades, which can serve as indicators of proton acceleration in young jets.

Contribution

It introduces Monte Carlo simulations to analyze hadronic gamma-ray emission from AGN lobes, emphasizing the significance of secondary cascades and their observational signatures.

Findings

Hadronic emission can dominate gamma-ray bands when primary emission is weak.

Secondary electron/positron synchrotron emission appears in GeV-TeV ranges.

Proton synchrotron emission is significant at sub MeV energies.

Abstract

Hadronic emission from parsec size radio lobes in active galactic nuclei (AGN) is discussed. The lobes are composed of shocked jet plasmaand expected to be filled with high energy particles. By using the Monte Carlo simulation, we calculate the photon spectra from the lobes including photo-meson interaction processes. When the synchrotron emission from primary electrons is bright, synchrotron-self-Compton component is dominant in gamma-ray bands. The hadronic emission from the lobes can be dominated in gamma-ray bands when the primary emission is not very bright. Proton synchrotron component arises at sub MeV band. The synchrotron emission radiated from secondary electron/positron pairs produced via photo-meson cascade emerges in GeV-TeV energy ranges. These high energy emission signatures provide a test for proton accelerations in young AGN jets.