Observational Properties of Nonthermal Emission from Relativistic Jets Escaping Active Galactic Nucleus Disks

TL;DR

This study models the propagation and emission signatures of relativistic jets from AGN disks, revealing key features like rapid deceleration, spectral shifts, and strong synchrotron self-absorption, with implications for multi-messenger astronomy.

Contribution

It provides a comprehensive simulation of jet dynamics and radiation in realistic AGN environments, highlighting observable signatures and their diagnostic potential.

Findings

Jets experience rapid deceleration and spectral downshift.

Strong synchrotron self-absorption creates a thermal hump.

Detectable multi-wavelength emissions outshine the AGN background.

Abstract

Relativistic jets launched from stellar-mass compact objects embedded in the accretion disk of an active galactic nucleus (AGN) can produce nonthermal emission upon successfully breaking out of the disk. In this paper, we present a comprehensive study of the long-term propagation dynamics and broadband nonthermal radiation signatures of such jets in a realistic AGN environment, explicitly modeled as wind outflows. Our modeling reveals two distinct features imprinted by the high-density AGN medium: rapid deceleration of the jet ejecta, accompanied by a prompt downshift of the emission spectral energy distribution, and persistently strong synchrotron self-absorption, giving rise to a prominent quasi-thermal hump in the emission spectrum. Crucially, both gamma-ray burst jets and jets powered by accreting binary black hole merger remnants can produce detectable multi-wavelength emissions that substantially outshine the AGN background. Moreover, the short time delays between gravitational wave triggers and these electromagnetic counterparts--typically less than 106 s--greatly facilitate secure multi-messenger associations. Besides, our findings highlight that interaction-induced radiation from AGN-embedded jet systems offers a powerful diagnostic probe of the spatial distribution,density structure, and physical properties of the AGN medium.