The Gamma-Ray Blazar PKS 0208-512, a Multi-Wavelength Investigation

TL;DR

This paper presents a multi-wavelength study of the gamma-ray blazar PKS 0208-512, analyzing its flaring activity across radio to gamma-ray frequencies, jet evolution, and timing of flares relative to jet components.

Contribution

It provides a detailed time series analysis and VLBI imaging of PKS 0208-512, revealing frequency-dependent lags and jet component evolution associated with gamma-ray flares.

Findings

Frequency-dependent lag between radio frequencies not due to optical depth.

Gamma-ray flares preceded by new jet components.

Jet evolution correlates with multi-wavelength flaring activity.

Abstract

The gamma-ray blazar PKS 0208-512 has shown strong periods of flaring, at all frequencies from radio to gamma-ray. This has led to its inclusion in the TANAMI project, which tracks the jets of southern AGN using VLBI as well as supporting flux density monitoring programs. Time series analysis of the light curves generated by such monitoring is presented and discussed and VLBI maps of the source are used to show the evolution in the jet. A frequency dependent lag is observed between flaring at different radio frequencies which does not appear to correspond to purely optical depth effects. Major flaring at gamma-ray frequencies appears to be preceded by a new component in the jet seen in our VLBI data.