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arXiv · 1711.06366

Modelling Baryonic Effects on Galaxy Cluster Mass Profiles

Abstract

Gravitational lensing is a powerful probe of the mass distribution of galaxy clusters and cosmology. However, accurate measurements of the cluster mass profiles are limited by uncertainties in cluster astrophysics. In this work, we present a physically motivated model of baryonic effects on the cluster mass profiles, which self-consistently takes into account the impact of baryons on the concentration as well as mass accretion histories of galaxy clusters. We calibrate this model using the Omega500 hydrodynamical cosmological simulations of galaxy clusters with varying baryonic physics. Our model will enable us to simultaneously constrain cluster mass, concentration, and cosmological parameters using stacked weak lensing measurements from upcoming optical cluster surveys.

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Masato Shirasaki, Erwin T. Lau, Daisuke Nagai. 2018-03-28. Modelling Baryonic Effects on Galaxy Cluster Mass Profiles. https://doi.org/10.1093/mnras%2Fsty763

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