V. C. Busti, R. N. Guimarães, J. A. S. Lima
A new method is proposed to measure the Hubble constant H0 through the mean
transmitted flux observed from high redshift quasars. A semi-analytical model
for the cosmological-independent volume density distribution function is
adopted which allows one to obtain constraints over the cosmological parameters
once a moderate knowlegde of the InterGalactic Medium (IGM) parameters is
assumed. By assuming a flat LCDM cosmology, we show that such method alone
cannot provide good constraints on the pair of free parameters (h, Omega_m).
However, it is possible possible to break the degeneracy on the mass density
parameter by applying a joint analysis involving the baryon acoustic
oscillations (BAOs). Our analysis based on two different samples of Lyman-alpha
forest restricts the parameters on the intervals 0.58 < h < 0.91 and 0.215 <
Omega_m < 0.245 (1 sigma). Although the constraints are weaker comparatively to
other estimates, we point out that with a bigger sample and a better knowledge
of the IGM this method may present competitive results to measure the Hubble
constant independently of the cosmic distance ladder.
View original:
http://arxiv.org/abs/1201.1260
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