Constraining $H_0$ from Sunyaev-Zel'dovich effect, Galaxy Clusters X-ray data, and Baryon Oscillations

Abstract

Estimates of $H_0$ from Sunyaev-Zel'dovich effect (SZE) and X-ray surface brightness of galaxy clusters depends on the underlying cosmology. In the current $\Lambda$CDM flat cosmology, a possible technique to broke the degenerescency on the mass density parameter (${\Omega }_m$) is to apply a joint analysis involving the baryon acoustic oscillations (BAO). By adopting this technique to the ($H_0,{\Omega }_m$) parameter space, we obtain new constraints on the Hubble constant $H_0$ from BAO signature as given by the Sloan Digital Sky Survey (SDSS) catalog. Our analysis based on the SZE/X-ray data for a sample of 25 clusters yields $H_0=74_{-3.5}^{+4}$ km s${}^{-1}$ Mpc${}^{-1}$ ($1\sigma$, neglecting systematic uncertainties). This result is in good agreement with independent studies from the {\it{Hubble Space Telescope}} key project and the recent estimates of WMAP, thereby suggesting that the combination of these three independent phenomena provides an interesting method to constrain the Hubble constant.

15 pages, 4 figures, 1 table