Multi-waveband Emission Maps of Blazars

TL;DR

This study presents multi-waveband emission maps of 34 gamma-ray bright blazars, combining radio to gamma-ray observations to locate emission regions, analyze flare timing, and infer jet magnetic field geometry.

Contribution

It introduces a comprehensive multi-waveband monitoring approach with high-resolution imaging to pinpoint blazar emission sites and analyze flare behaviors.

Findings

Flares can occur simultaneously across wavebands or be frequency-specific.

Flares are often triggered by superluminal knots passing the VLBA core.

Emission regions are located both upstream and downstream of the core.

Abstract

We are leading a comprehensive multi-waveband monitoring program of 34 gamma-ray bright blazars designed to locate the emission regions of blazars from radio to gamma-ray frequencies. The "maps" are anchored by sequences of images in both total and polarized intensity obtained with the VLBA at an angular resolution of ~ 0.1 milliarcseconds. The time-variable linear polarization at radio to optical wavelengths and radio to gamma-ray light curves allow us to specify the locations of flares relative to bright stationary features seen in the images and to infer the geometry of the magnetic field in different regions of the jet. Our data reveal that some flares occur simultaneously at different wavebands and others are only seen at some of the frequencies. The flares are often triggered by a superluminal knot passing through the stationary "core" on the VLBA images. Other flares occur upstream or even parsecs downstream of the core.