VLBI Monitoring of 3C 84 in Gamma-ray Active Phase

TL;DR

This study uses multi-epoch VLBI observations to analyze the innermost jet of 3C 84 during a gamma-ray active phase, revealing a new component's emergence and its relation to gamma-ray emission.

Contribution

It provides the first detailed VLBI kinematic analysis of 3C 84 during a gamma-ray active phase, linking jet activity with gamma-ray emission mechanisms.

Findings

A new jet component emerged during the outburst.

The component's projected speed was approximately 0.23c.

The gamma-ray emission site is associated with the central ~1 pc core.

Abstract

We report multi-epoch Very Long Baseline Interferometry (VLBI) study of the innermost jet of 3C 84. We carried out 14-epoch VLBI observations during 2006-2009 with the Japanese VLBI Network (JVN) and the VLBI Exploration of Radio Astrometry (VERA), immediately following the radio outburst that began in 2005. Comparison between VLBI lightcurve and single-dish lightcurve indicates that the outburst was associated with the central ~1 pc core. We found that this outburst accompanied the emergence of a new component, and the projected speed of this new component was 0:23c from 2007/297 (2007 October 24) to 2009/114 (2009 April 24). We argue the site of gamma-ray emission detected by Fermi/LAT and jet kinematics in connection with gamma-ray emission mechanism.