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Generalized Chaplygin gas model: constraints from Hubble parameter versus Redshift Data

Puxun Wu·Hongwei Yu
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Abstract

We examine observational constraints on the generalized Chaplygin gas (GCG) model for dark energy from the 9 Hubble parameter data points, the 115 SNLS Sne Ia data and the size of baryonic acoustic oscillation peak at redshift, $z=0.35$. At a 95.4% confidence level, a combination of three data sets gives $0.67\leq A_s\leq 0.83$ and $-0.21\leq α\leq 0.42$, which is within the allowed parameters ranges of the GCG as a candidate of the unified dark matter and dark energy. It is found that the standard Chaplygin gas model ($α=1$) is ruled out by these data at the 99.7% confidence level.

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Puxun Wu, Hongwei Yu. 2006-12-09. Generalized Chaplygin gas model: constraints from Hubble parameter versus Redshift Data. https://doi.org/10.1016/j.physletb.2006.11.028

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