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arXiv · 1709.00646

Bayesian correction of $H(z)$ data uncertainties

J. F. Jesus·T. M. Gregório·F. Andrade-Oliveira·R. Valentim·C. A. O. Matos
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Abstract

We compile 41 $H(z)$ data from literature and use them to constrain O$Λ$CDM and flat $Λ$CDM parameters. We show that the available $H(z)$ suffers from uncertainties overestimation and propose a Bayesian method to reduce them. As a result of this method, using $H(z)$ only, we find, in the context of O$Λ$CDM, $H_0=69.5\pm2.5\mathrm{\,km\,s^{-1}Mpc^{-1}}$, $Ω_m=0.242\pm0.036$ and $Ω_Λ=0.68\pm0.14$. In the context of flat $Λ$CDM model, we have found $H_0=70.4\pm1.2\mathrm{\,km\,s^{-1}Mpc^{-1}}$ and $Ω_m=0.256\pm0.014$. This corresponds to an uncertainty reduction of up to 30\% when compared to the uncorrected analysis in both cases.

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J. F. Jesus, T. M. Gregório, F. Andrade-Oliveira, R. Valentim, C. A. O. Matos. 2017-10-11. Bayesian correction of $H(z)$ data uncertainties. https://doi.org/10.1093/mnras%2Fsty813

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