AGN activity and IGM heating in fossil cluster RX J1416.4+2315

TL;DR

This study investigates AGN activity in the fossil cluster RX J1416.4+2315, revealing limited IGM heating by radio lobes, cavity formation, and assessing the AGN's energy contribution to cluster cooling.

Contribution

First detailed radio and X-ray analysis of AGN activity and IGM heating in a fossil galaxy cluster, highlighting the limited heating effect and cavity energetics.

Findings

Radio lobe extends from the central nucleus at 610 MHz.

Energy injection heats only the central 50 kpc, smaller than the cooling radius (~130 kpc).

Total energy in cavities can offset radiative cooling.

Abstract

We study Active Galactic Nucleus (AGN) activity in the fossil galaxy cluster, RX J1416.4+2315. Radio observations were carried out using Giant Metrewave Radio Telescope (GMRT) at two frequencies, 1420 MHz and 610 MHz. A weak radio lobe that extends from the central nucleus is detected in 610 MHz map. Assuming the radio lobe originated from the central AGN, we show the energy injection into the Inter Galactic Medium (IGM) is only sufficient to heat up the central 50 kpc within the cluster core, while the cooling radius is larger ( $\sim$ 130 kpc). In the hardness ratio map, three low energy cavities have been identified. No radio emission is detected for these regions. We evaluated the power required to inflate the cavities and showed that the total energy budget is sufficient to offset the radiative cooling. We showed that the initial conditions would change the results remarkably. Furthermore, efficiency of Bondi accretion to power the AGN has been estimated.