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We study how X-rays from stellar binary systems and the hot intracluster medium (ICM) affect the radiative cooling rates of gas in galaxies. Our study uses a novel implementation of gas cooling in the moving-mesh hydrodynamics code textsc{arepo}. X-rays from stellar binaries do not affect cooling at all as their emission spectrum is too hard to effectively couple with galactic gas. In contrast, X-rays from the ICM couple well with gas in the temperature range $10^4 - 10^6$ K. Idealised simulations show that the hot halo radiation field has minimal impact on the dynamics of cooling flows in clusters because of the high virial temperature ($> 10^7$K), making the interaction between the gas and incident photons very ineffective. Satellite galaxies in cluster environments, on the other hand, experience a high radiation flux due to the emission from the host halo. Low mass satellites ($< 10^{12}rm{M_odot}$) in particular have virial temperatures that are exactly in the regime where the effect of the radiation field is maximal. Idealised simulations of satellite galaxies including only the effect of host halo radiation (no ram pressure stripping or tidal effects) fields show a drastic reduction in the amount of cool gas formed ($sim 40%$) on a short timescale of about $0.5$ Gyrs. A galaxy merger simulation including all the other environmental quenching mechanisms, shows about $20%$ reduction in the stellar mass of the satellite and about $sim 30%$ reduction in star formation rate after $1$ Gyr due to the host hot halo radiation field. These results indicate that the hot halo radiation fields potentially play an important role in quenching galaxies in cluster environments.
The thermal Sunyaev-Zeldovich (SZ) effect and soft X-ray emission are routinely observed around massive galaxies and in galaxy groups and clusters. We study these observational diagnostics of galaxy haloes for a suite of cosmological `zoom-in simulat
We examine X-ray emission produced from hot gas during collisions and mergers of disk galaxies. To study this process, we employ simulations that incorporate cosmologically motivated disk-galaxy models and include the effects of radiative cooling, st
To investigate the effect of feedback from active galactic nuclei (AGN) on their surrounding medium, we study the diffuse X-ray emission from galaxy groups and clusters by coupling the Astrophysical Plasma Emission Code (APEC) with the cosmological h
It has long been suspected that powerful radio sources may lower the efficiency with which stars form from the molecular gas in their host galaxy, but so far, alternative mechanisms, in particular related to the stellar mass distribution in the massi
We present a first study of the effect of local photoionising radiation on gas cooling in smoothed particle hydrodynamics simulations of galaxy formation. We explore the combined effect of ionising radiation from young and old stellar populations. Th