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The intracluster medium (ICM) pervades the dark matter halo of galaxy clusters and is intimately linked to the evolution of the member galaxies through the cosmic baryon cycle. Jets driven by active galactic nuclei (AGNs), sloshing by passage of galaxies during infall and mergers can drive turbulence in the ICM. Turbulence plays an important role in cluster thermodynamics through turbulent heating and turbulent mixing and can prevent runaway cooling in cool cores. On larger scales, it affects cluster mass measurements by providing non-thermal pressure support to the gas, causing gas profiles to deviate from hydrostatic equilibrium. However, current X-ray observations lack the spectral resolution to directly measure turbulent velocities in the hot ICM. The different indirect observational methods of measuring turbulence include X-ray brightness fluctuations, thermal Sunyaev Zeldovich effect (tSZ) fluctuations and velocity measurements of cold (10^4 K) Halpha emitting filaments using integral field unit spectroscopy (IFU). Using our idealised simulations, we have studied the effects of the gas density stratification, amount of turbulent heating and the method of driving (incompressible vs compressible) on different statistical properties of the ICM gas, such as its temperature and density distribution, velocities of hot (10^7 K gas) and cold (10^4 K) phases, etc. We use our results to constrain the different indirect observational techniques for measuring turbulent velocities, such as X-ray brightness fluctuations, thermal Sunyaev-Zeldovich effect fluctuations, which are dependent on the density and pressure fluctuations, respectively. We also correlate between the velocities of hot (10^7 K gas) and cold (10^4 K) phases which would let us recover hot phase velocities from IFU observations of the cold phase. |
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