Hydrodynamics of a perturbation in the jet of 3C111

TL;DR

This paper models the ejection of a superluminal component in the jet of 3C111 using relativistic hydrodynamics, explaining brightness evolution through dense material injection and ruling out alternative scenarios.

Contribution

It introduces a hydrodynamic model for jet perturbations in 3C111 that accurately reproduces observed brightness changes, advancing understanding of jet dynamics.

Findings

Model successfully reproduces brightness evolution of jet features.

Injection of dense material explains superluminal component ejection.

Alternative scenarios like increased Lorentz factor are inconsistent with observations.

Abstract

We present results on the modelling of the ejection of a superluminal component in the jet of 3C111. We propose that the component is generated by an injection of dense material followed by a decrease in the injection rate of bulk particles in the jet. Our model is supported by 1D relativistic hydrodynamics and emission simulations, and is capable of reproducing the brightness evolution of two features, as revealed by 15 GHz VLBA observations. We show that other scenarios, such as an increase of the Lorentz factor in the material of the perturbation, fails to reproduce the observed evolution of this flare.