mm-VLBI observations of the active galaxy 3C 111 in outburst

TL;DR

This study uses high-resolution millimeter VLBI observations to analyze the jet structure and dynamics of the active galaxy 3C 111 following a major radio outburst, revealing complex plasma ejections and velocity variations.

Contribution

First high-resolution millimeter VLBI imaging of 3C 111's jet during an outburst, providing detailed insights into jet kinematics close to the core.

Findings

Jet components form a bent structure within 1 mas from the core.

Ejections vary in position angle during the outburst.

Apparent velocities of jet components are around 3.7c, slower than larger-scale velocities.

Abstract

The broad-line radio galaxy 3C 111 exhibited a major flux density outburst in 2007. Here, we present imaging and preliminary kinematic results of the jet, based on three millimetre-VLBI observations (86 GHz) using the Global Millimeter VLBI Array (GMVA) covering one year just after the radio flare. The GMVA data allow us to study this outburst with unprecedented image fidelity at highest (sub-parsec) resolution. On these scales, the outburst is resolved into a complex series of plasma components forming an intriguing bent structure. Within 1 mas from the jet base, ejections vary in position angle and components move with an apparent velocity of ~3.7c, significantly slower than the maximum velocity observed with cm-VLBI on scales beyond 1 mas.