FR0 radio galaxy jets -- I. linking jet dynamics and high-energy emission in LEDA 55267 and LEDA 58287

TL;DR

This study combines relativistic hydrodynamical simulations with broadband spectral modeling to understand the dynamics and high-energy emission of compact FR0 radio galaxy jets, predicting a significant role for lepto-hadronic processes at TeV energies.

Contribution

It provides the first detailed simulation-based link between jet dynamics and high-energy emission in FR0 galaxies, emphasizing the importance of recollimation shocks and magnetization.

Findings

Recollimation shocks induce turbulence and deceleration, limiting jet propagation.

Leptonic models fit radio to GeV emission; lepto-hadronic models favored at TeV energies.

Simulations predict strong TeV emission from lepto-hadronic processes, testable by future observations.

Abstract

Fanaroff-Riley type 0 (FR0) radio galaxies host anomalously compact jets whose disruption mechanism and high-energy emission remain poorly understood. We combine three-dimensional relativistic hydrodynamical (RHD) simulations with broadband spectral energy distribution (SED) modeling from radio to TeV energies, focusing on LEDA~55267 and LEDA~58287. Our simulations show that recollimation shocks trigger hydrodynamical instabilities that drive turbulence and rapid deceleration, preventing the jets from propagating beyond a few tens of parsecs and reproducing the observed compact radio morphology. Leptonic SED models adequately describe the observed emission up to GeV energies, but when simulated CTAO observations are included, statistical model comparison indicates strong evidence in favor of lepto-hadronic scenarios at TeV energies for both sources, a result that should be interpreted as a theoretical prediction to be tested by future observations. A leptonic analysis of the simulations reveals magnetized emitting regions with plasma beta parameters $\beta_{\rm p} \sim 10^{-5}$-$10^{-3}$, orders of magnitude below values reported for extended FRI jets, consistent with jets retaining the magnetization inherited from the launching region and providing a natural physical link between the compact jet dynamics and the lepto-hadronic emission.