A lepto-hadronic multi-zone framework for studying neutrino emissions from AGN jets

Abstract

Active Galactic Nuclei (AGN) and their relativistic jets have been a topic of interest in astronomy for decades, yet the matter composition of these relativistic jets is still not clearly known. Different models for the jet composition have been proposed in order to explain the high energy peak observed in the blazar SEDs, starting from the leptonic models, hadronic models to the lepto-hadronic model which combines both. Particles can be accelerated inside AGN jets via different mechanisms, including shocks, stochastic turbulent acceleration and magnetic reconnection. This can generate distinct multi-messenger observational signatures due to the rapid changes in magnetic field topology in the emission zone. These signatures can be used as pivotal diagnostic tools to study different jet composition models. The detection of neutrinos coming from the direction of blazar TXS 0506+056 by IceCube Neutrino Observatory, has renewed the interest in hadronic and lepto-hadronic jet models, as these models inherently produce neutrinos. While there exists numerical codes modeling single-zone lepto-hadronic scenarios in AGN jets, the availability of comprehensive multi-zone codes is limited. To tackle this notable gap in the field of lepto-hadronic modeling, we have developed a numerical multi-zone framework for lepto-hadronic modeling of AGN jets by building upon the foundation of existing single zone codes. This framework serves as a bridge between jet dynamics and the microphysics within AGN jets, aiming to create synergy between relativistic magneto-hydrodynamic simulations and multi-messenger observations. We apply this multi-zone framework to model the multi-wavelength and neutrino emission from the jet. This approach provides valuable insights into how the interplay of jet dynamics, particle acceleration mechanisms, and jet composition shapes the resulting multi-messenger signals. © Copyright owned by the author(s)