The Polarization Behavior of Relativistic Synchrotron Jets

TL;DR

This paper presents a geometric model for polarization in blazar jets, incorporating turbulence, jet divergence, and relativistic effects, aligning with recent observations and predicting new polarization behaviors.

Contribution

It introduces a comprehensive geometric model for synchrotron polarization in blazar jets, accounting for relativistic effects and turbulence, to better interpret observational data.

Findings

Polarization behavior matches recent monitoring data.

Predicted relativistic steps in PA rotation rate.

Enhanced waveband differences in polarization signals.

Abstract

We describe a geometric model for synchrotron radiation from blazar jets, involving multiple emission zones with turbulent magnetic fields and a transient core with a helical B field. Including the effects of jet divergence, particle cooling and the Relativistic PA rotation (RPAR) to the observer frame, we find polarization behavior consistent with recent data from monitoring campaigns. We predict that under some circumstances multi-$\pi$ rotation phases should exhibit relativistically-induced steps in rate $d{\rm PA}/dt$ and modulation in polarization $\Pi$ that can be helpful in pinning down the jet $\Gamma$ and $\theta_{\rm obs}$. Also, RPAR enhances waveband differences that will be particularly interesting for comparing radio, optical and, soon, X-ray PA and $\Pi$ variations.