# Powerful AGN jets and unbalanced cooling in the hot atmosphere of IC 4296

## TL;DR

This study combines radio, X-ray, and optical observations to analyze powerful AGN jets in IC 4296, revealing their impact on the galaxy's hot atmosphere and the ongoing cooling and feeding processes of the central black hole.

## Contribution

It provides detailed multi-wavelength analysis of AGN jets and their interaction with the hot atmosphere in IC 4296, highlighting the energy deposition far from the nucleus.

## Key findings

- Radio jets deposit most energy into the ICM.
- Presence of X-ray cavities associated with radio lobes.
- Jets are expanding supersonically, creating bow shocks.

## Abstract

We present new Karl G. Jansky Very Large Array (VLA, 1.5 GHz) radio data for the giant elliptical galaxy IC 4296, supported by archival radio, X-ray (Chandra, XMM-Newton) and optical (SOAR, HST) observations. The galaxy hosts powerful radio jets piercing through the inner hot X-ray emitting atmosphere, depositing most of the energy into the ambient intra-cluster medium (ICM). Whereas the radio surface brightness of the A configuration image is consistent with a Fanaroff-Riley Class I (FR I) system, the D configuration image shows two bright, relative to the central region, large (~160 kpc diameter), well-defined lobes, previously reported by Killeen et al., at a projected distance r~>230 kpc. The XMM-Newton image reveals an X-ray cavity associated with one of the radio lobes. The total enthalpy of the radio lobes is ~7x10^59 erg and the mechanical power output of the jets is ~10^44 erg/s. The jets are mildly curved and possibly re-brightened by the relative motion of the galaxy and the ICM. The lobes display sharp edges, suggesting the presence of bow shocks, which would indicate that they are expanding supersonically. The central entropy and cooling time of the X-ray gas are unusually low and the nucleus hosts a warm H\alpha+[NII] nebula and a cold molecular CO disk. Because most of the energy of the jets is deposited far from the nucleus, the atmosphere of the galaxy continues to cool, apparently feeding the central supermassive black hole and powering the jet activity.