Jet-ISM interaction in NGC 1167 / B2 0258+35, A LINER with an AGN past

TL;DR

This study investigates the interaction between a young radio jet and the interstellar medium in NGC 1167, revealing evidence of past AGN activity and jet-induced ISM compression through multi-wavelength observations and hydrodynamic simulations.

Contribution

It provides new insights into jet-ISM interactions and the evolutionary history of NGC 1167's AGN activity using combined X-ray observations and tailored hydrodynamic modeling.

Findings

Extended X-ray emission aligned with the jet and orthogonal to it.

Evidence of past high accretion activity in the AGN.

Hydrodynamic simulations support jet-induced ISM compression.

Abstract

We report the results of joint Chandra/ACIS - NuSTAR deep observations of NGC 1167, the host galaxy of the young radio jet B2 0258+35. In the ACIS data we detect X-ray emission, extended both along and orthogonal to the jet. At the end of the SE radio jet, we find lower-energy X-ray emission that coincides with a region of CO turbulence and fast outflow motions. This suggests that the hot Interstellar Medium (ISM) may be compressed by the jet and molecular outflow, resulting in more efficient cooling. Hydrodynamic simulations of jet-ISM interaction tailored to NGC 1167 are in agreement with this conclusion and with the overall morphology and spectra of the X-ray emission. The faint hard nuclear source detected with Chandra and the stringent NuSTAR upper limits on the harder X-ray emission show that the active galactic nucleus (AGN) in NGC 1167 is in a very low-accretion state. However, the characteristics of the extended X-ray emission are more consonant to those of luminous Compton Thick AGNs, suggesting that we may be observing the remnants of a past high accretion rate episode, with sustained strong activity lasting ~ 2 x 103 yr. We conclude that NGC1167 is presently a LINER, but was an AGN in the past, given the properties of the extended X-ray emission and their similarity with those of CT AGN extended emission.