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arXiv · 0807.0647

New constraints on H_0 and Omega_M from SZE/X-RAY data and Baryon Acoustic Oscillations

R. F. L. Holanda·J. V. Cunha·J. A. S. Lima
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Abstract

The Hubble constant, $H_0$, sets the scale of the size and age of the Universe and its determination from independent methods is still worthwhile to be investigated. In this article, by using the Sunyaev-Zel`dovich effect and X-ray surface brightness data from 38 galaxy clusters observed by Bonamente {\it{et al.}} (2006), we obtain a new estimate of $H_0$ in the context of a flat $\Lambda$CDM model. There is a degeneracy on the mass density parameter ($\Omega_{m}$) which is broken by applying a joint analysis involving the baryon acoustic oscillations (BAO) as given by Sloan Digital Sky Survey (SDSS). This happens because the BAO signature does not depend on $H_0$. Our basic finding is that a joint analysis involving these tests yield $H_0= 0.765^{+0.035}_{-0.033}$ km s$^{-1}$ Mpc$^{-1}$ and $\Omega_{m}=0.27^{+0.03}_{-0.02}$. Since the hypothesis of spherical geometry assumed by Bonamente {\it {et al.}} is questionable, we have also compared the above results to a recent work where a sample of triaxial galaxy clusters has been considered.

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R. F. L. Holanda, J. V. Cunha, J. A. S. Lima. 2008-07-03. New constraints on H_0 and Omega_M from SZE/X-RAY data and Baryon Acoustic Oscillations. https://doi.org/10.1007/s10714-011-1292-5

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