Weighing simulated galaxy clusters using lensing and X-ray

Context. Measuring the mass of galaxy clusters is a key issue in cosmology. Among the methods employed to achieve this goal, the techniques based on lensing and X-ray analyses are perhaps the most widely used. However, the comparison between these mass estimates is often difficult and, in several clusters, the results apparently are inconsistent. Aims. We aim at investigating potential biases in lensing and X-ray methods to measure the cluster mass profiles. Methods. We do so by performing realistic simulations of lensing and X-ray observations that are subsequently analyzed using observational techniques. The resulting mass estimates are compared among them and with the input models. Three clusters obtained from state-of-the-art hydrodynamical simulations, each of which has been projected along three independent lines-of-sight, are used for this analysis. Results. We find that strong lensing models can be trusted over a limited region around the cluster core. Extrapolating the strong lensing mass models to outside the Einstein ring can lead to significant biases in the mass estimates, if the BCG is not modeled properly for example. Weak lensing mass measurements can be largely affected by substructures, depending on the method implemented to convert the shear into a mas