Monitoring blazar variability to understand extragalactic jets

TL;DR

This paper reviews how multiwavelength variability studies of blazars reveal insights into the physics, structure, and dynamics of extragalactic jets and their central engines.

Contribution

It synthesizes current knowledge on blazar variability, highlighting key mechanisms, observational correlations, and periodicities to advance understanding of jet physics.

Findings

Cross-correlation between flux variations at different frequencies analyzed.

Mechanisms for long-term and short-term variability discussed.

Periodicities in multiwavelength light curves identified.

Abstract

We review the main topics in the field of blazar multiwavelength variability as a tool to understand the physics and structure of extragalactic jets and their central engine. We address issues such as the cross-correlation between flux variations at different frequencies, the mechanisms to explain the long-term and short-term variability, the size of the jet emitting regions, the polarization behaviour, and the periodicities detected in the multiwavelength light curves.