Resolving the hydrostatic mass profiles of galaxy clusters at z~1 with XMM-Newton and Chandra

We present a detailed study of the integrated total hydrostatic mass profiles of the five most massive ($M_{500} > 5 \times 10^{14} M_{\odot}$) galaxy clusters selected at z$\sim$1 via the Sunyaev-Zel'dovich effect. These objects represent an ideal laboratory to test our models in a mass regime where structure formation is driven mainly by gravity. Optimally exploiting spatially-resolved spectroscopic information from XMM-Newton and Chandra observations, we used both parametric (foward, backward) and non-parametric methods to recover the mass profiles, finding that the results are extremely robust when density and temperature measurements are available. Our X- ray masses at $R_{500}$ are higher than weak lensing masses obtained from the Hubble Space Telescope (HST), at odds with a scenario where the hydrostatic method yields a biased, underestimated, mass. We investigated halo shape parameters such as sparsity and concentration, and compared to local X-ray selected clusters, finding hints for evolution in the central regions (or for selection effects). The total baryonic content is in agreement with the cosmic value at $R_{500}$. Comparison with numerical simulations shows that the mass distribution and concentration are in line with expectations. These results illustrate the power of X-ray observations to probe the statistical properties of the gas and total mass profiles in this high mass, high-redshift regime.