GMVA21B-164

Moving and stationary shocks interaction after a gamma-ray flare in TXS2013+370

Abstract

The blazar TXS 2013+370 showed extraordinary flaring activity at gamma-rays on 06 December 2020, detected by the FERMI satellite. The observed flux variability is the highest ever recorded since 2009. At the same time, the source is also flaring in the optical, NIR and mm-radio bands. In the mm-radio-bands the flux density is now rising. We propose to observe the source with the GMVA at 3 mm (and in gaps at 7mm with VLBA), in order to follow expected structural variations at the jet base in total intensity and polarisation. We intend to study the kinematic and spectral evolution of the inner-most jet region during the ongoing flaring activity. In particular we like to check if the jet is helically bent and how newly expected jet components travel through the 0.1-0.2 mas region, where a stationary component is located. This passage could trigger additional gamma-ray flares and should alter the jet polarisation. The spectral variations of newly expelled jet plasma will be used to test the Daly & Marscher model, in particular with regard to the physical parameters at the jet base during the inverse Compton/synchrotron cooling phase.

Investigators

Name	Institution
GBT Operator	Green Bank Observatory
Tony Zensus	National Radio Astronomy Observatory; Max-Planck-Institut für Radioastronomie
Uwe Bach	Max-Planck-Institut für Radioastronomie
Eduardo Ros	Max-Planck-Institut für Radioastronomie; València, Universitat de
Dongjin Kim	Massachusetts Institute of Technology
Roberto Angioni	Max-Planck-Institut für Radioastronomie
Anne-Kathrin Baczko	Max-Planck-Institut für Radioastronomie; Chalmers University Of Technology
Biagina Boccardi	Max-Planck-Institut für Radioastronomie
Thomas Krichbaum	Max-Planck-Institut für Radioastronomie
Matthias Kadler	Würzburg, Universität
Efthalia Traianou *	Max-Planck-Institut für Radioastronomie; Köln, Universität zu; Andalucía, Instituto de Astrofísica de

* indicates the PI