G17A004

Probing the Innermost Regions of AGN Jets and their Magnetic Fields

Abstract

The RadioAstron Key Science Program (KSP) on AGN Polarization has confirmed the
polarization imaging capabilities of the space radio telescope and probed the innermost
regions of AGN jets and their magnetic fields at resolutions down to 20 microarcseconds.
Based on these results, we have proposed to extend this KSP through the AO-5 period of
RadioAstron, and we request here the GVLBI support for these RadioAstron KSP
observations. The AO-5 observations will target five prominent AGN, combining the
RadioAstron data and ground-based C/X/U/Q band observations (during gaps between the
RadioAstron scans) to perform detailed multifrequency polarization imaging, Faraday rotation
studies, and spectral analysis of compact emission. With this information, we will reconstruct
the magnetic field structure and study the physical properties of the jets in the vicinity of the
central engine. The AO-5 period offers also a unique opportunity for quasi-simultaneous
RadioAstron (1.3 cm), GMVA (3 mm), and EHT (1 mm) observations of our targets in autumn
2017 and spring 2018, including the participation of phased-ALMA. The resolution-matched
images will allow opacity and Faraday rotation studies at unprecedented high angular
resolutions.

Investigators

Name	Institution
Tony Zensus	National Radio Astronomy Observatory; Max-Planck-Institut für Radioastronomie
Greg Taylor	New Mexico, University of
Bong Won Sohn	Korea Astronomy and Space Science Institute
Eduardo Ros	Max-Planck-Institut für Radioastronomie; València, Universitat de
Manel Perucho	València, Universitat de
Miguel Perez-Torres	Andalucía, Instituto de Astrofísica de
Sang-Sung Lee	Korea Astronomy and Space Science Institute
Mason Keck	Boston University
Daniel Homan	Denison University
Christan Fromm	Max-Planck-Institut für Radioastronomie; Frankfurt am Main, Goethe-Universität
Jean Eilek	National Radio Astronomy Observatory; New Mexico Institute of Mining and Technology
Timothy Cawthorne	Lancashire, University of Central
Carolina Casadio	Andalucía, Instituto de Astrofísica de; Max-Planck-Institut für Radioastronomie; Foundation for Research & Technology - Hellas
Michael Bell
Uwe Bach	Max-Planck-Institut für Radioastronomie
James Anderson	Deutsches GeoForschungsZentrum
Antonio Alberdi	Andalucía, Instituto de Astrofísica de
Ivan Agudo	Boston University; Joint Institute for Very Long Baseline Interferometry European Research Infrastructure Consortium; Andalucía, Instituto de Astrofísica de; Andalucía, Instituto de Astrofísica de
Kazunori Akiyama	Massachusetts Institute of Technology; Haystack Observatory
Rusen Lu	Max-Planck-Institut für Radioastronomie
Stefanie Komossa	Max-Planck-Institut für Radioastronomie
Thomas Kirchbaum	Max-Planck-Institut für Radioastronomie
Svetlana Jorstad	Boston University
Alan Marscher	Boston University
Kazuhiro Hada	National Astronomical Observatory of Japan
Tuomas Savolainen	Max-Planck-Institut für Radioastronomie; Aalto yliopisto
Kirill Sokolovsky	Illinois at Urbana-Champaign, University of
Antonio Fuentes	Andalucía, Instituto de Astrofísica de
Laura Vega-Garcia	Max-Planck-Institut für Radioastronomie
Yuri Kovalev	Green Bank Observatory
Gabriele Bruni	Istituto Nazionale di Astrofisica
Andrei Lobanov	Max-Planck-Institut für Radioastronomie
Jose L. Gomez *	Andalucía, Instituto de Astrofísica de
GBT Operator	Green Bank Observatory

* indicates the PI