http://arxiv.org/abs/1809.09560
The possibility to determine the value of the Hubble constant using observations of galaxy clusters in X-ray and microwave wavelengths via Sunyaev Zel’dovich (SZ) effect has been long known about. Previous measurements have been plagued by relatively large errors in the observational data and severe biases induced, for example, by cluster triaxiality and clumpiness. The advent of Planck allows to map the Compton parameter y, i.e. the amplitude of the SZ effect, with unprecedented accuracy at intermediate cluster-centric radii allowing to perform detailed spatially resolved comparison with X-ray measurements. Given such higher quality observational data, we developed a bayesian approach that combines informed priors on the physics of the ICM obtained from hydrodynamical simulations of massive clusters with measurement uncertainties.
We apply our method to a sample of 61 galaxy clusters with redshifts up to z < 0.5 observed with Planck and XMM-Newton observations and find H_0=67 \pm 3 km s^{-1} Mpc^{-1}.
A. Kozmanyan, H. Bourdin, P. Mazzotta, et. al.
Wed, 26 Sep 18
28/69
Comments: 15 pages, 9 figures, accepted for publication by A&A
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