GMVA23A-033

Revealing the jet launching in 3C84 at the highest detail

Abstract

3C84 is a radio galaxy displaying a unique combination of brightness, large black hole mass and proximity. Its jet exhibits intermittent activity, offering a distinctive opportunity to study the inner jet and core region with high spatial resolution; down to ~45 Schwarzschild radii for the GMVA beam. Presently it is unclear if the jet base of 3C84 is as large as a recent RadioAstron image suggested. High resolution, spectral index images help discriminate between locations of the jet apex. We thus propose a new GMVA imaging to complement quasi-simultaneous observations with the EHT (230 GHz). We request 1 session with which we will specifically try to 1) locate the jet apex within the northern region, 2) make a 86/230 GHz spectral index map, 3) determine the transverse jet width and size of the jet apex, 4) measure the polarisation, 5) measure the jet-to-counter-jet ratio near the jet base to better constrain jet viewing angle and torus properties. In combination with earlier epochs, the proposed observations will clarify the physical cause of the "jet wobbling", discriminating between BBH precession and jet formation induced rotation.

Investigators

Name	Institution
Michael Bremer	Institut de Radio Astronomique Millimétrique
Tuomas Savolainen	Max-Planck-Institut für Radioastronomie; Aalto yliopisto
Jeffrey Hodgson	Max-Planck-Institut für Radioastronomie; Korea Astronomy and Space Science Institute
Junghwan Oh	Korea Astronomy and Space Science Institute
Efthalia Traianou	Max-Planck-Institut für Radioastronomie; Köln, Universität zu; Andalucía, Instituto de Astrofísica de
Jae-Young Kim	Max-Planck-Institut für Radioastronomie; Kyungpook National University
Tony Zensus	National Radio Astronomy Observatory; Max-Planck-Institut für Radioastronomie
Thomas Krichbaum	Max-Planck-Institut für Radioastronomie
Georgios Filippos Paraschos *	Max-Planck-Institut für Radioastronomie
GBT Operator	Green Bank Observatory

* indicates the PI