Dynamics of relativistic radio jets in asymmetric environments

TL;DR

This study uses 3D relativistic simulations to explore how asymmetric environments influence the morphology and evolution of high-power radio jets, revealing environment-driven asymmetries consistent with observations.

Contribution

First detailed relativistic 3D simulations of radio jets in asymmetric environments, linking environmental differences to observed lobe asymmetries.

Findings

Jets develop typical FR II morphology despite instability.

Denser environments produce shorter lobes and brighter hotspots.

Environmental asymmetry correlates with lobe length asymmetry.

Abstract

We have carried out relativistic three-dimensional simulations of high-power radio sources propagating into asymmetric cluster environments. We offset the environment by 0 or 1 core radii (equal to 144 kpc), and incline the jets by 0, 15, or 45{\deg} away from the environment centre. The different environment encountered by each radio lobe provides a unique opportunity to study the effect of environment on otherwise identical jets. We find that the jets become unstable towards the end of the simulations, even with a Lorentz factor of 5; they nevertheless develop typical FR II radio morphology. The jets propagating into denser environments have consistently shorter lobe lengths and brighter hotspots, while the axial ratio of the two lobes is similar. We reproduce the recently reported observational anti-correlation between lobe length asymmetry and environment asymmetry, corroborating the notion that observed large-scale radio lobe asymmetry can be driven by differences in the underlying environment.