# Unveiling the AGN in IC 883: discovery of a parsec-scale radio jet

## TL;DR

This study provides definitive radio evidence of an active low-luminosity AGN in IC 883, revealing a parsec-scale jet, a young GPS source, and insights into AGN-starburst transition in a luminous infrared galaxy.

## Contribution

It reports the first direct radio detection of a parsec-scale jet and a young GPS source in IC 883, highlighting the AGN's role in a starburst galaxy and its evolutionary implications.

## Key findings

- Detection of a core-jet morphology at sub-parsec scales.
- Identification of a young (~3000 yr) gigahertz-peaked spectrum (GPS) source.
- Evidence of a low-accretion rate AGN with high bolometric luminosity.

## Abstract

IC883 is a luminous infrared galaxy (LIRG) classified as a starburst-active galactic nucleus (AGN) composite. In a previous study we detected a low-luminosity AGN (LLAGN) radio candidate. Here we report on our radio follow-up at three frequencies which provides direct and unequivocal evidence of the AGN activity in IC883. Our analysis of archival X-ray data, together with the detection of a transient radio source with luminosity typical of bright supernovae, give further evidence of the ongoing star formation activity, which dominates the energetics of the system. At sub-parsec scales, the radio nucleus has a core-jet morphology with the jet being a newly ejected component showing a subluminal proper motion of 0.6c-1c. The AGN contributes less than two per cent of the total IR luminosity of the system. The corresponding Eddington factor is ~1E-3, suggesting this is a low-accretion rate engine, as often found in LLAGNs. However, its high bolometric luminosity (~10E44erg/s) agrees better with a normal AGN. This apparent discrepancy may just be an indication of the transition nature of the nucleus from a system dominated by star-formation, to an AGN-dominated system. The nucleus has a strongly inverted spectrum and a turnover at ~4.4GHz, thus qualifying as a candidate for the least luminous (L_5.0GHz ~ 6.3E28erg/s/Hz) and one of the youngest (~3000yr) gigahertz-peaked spectrum (GPS) sources. If the GPS origin for the IC883 nucleus is confirmed, then advanced mergers in the LIRG category are potentially key environments to unveil the evolution of GPS sources into more powerful radio galaxies.