Combined constraints on modified Chaplygin gas model from cosmological observed data: Markov Chain Monte Carlo approach

TL;DR

This paper employs Markov Chain Monte Carlo methods to constrain the modified Chaplygin gas model using diverse cosmological observational data, providing updated parameter bounds for a unified dark matter and dark energy scenario.

Contribution

It introduces a comprehensive MCMC analysis combining multiple datasets to tightly constrain the parameters of the modified Chaplygin gas model in a flat universe.

Findings

Parameter constraints for the MCG model with 1σ and 2σ confidence levels.

Consistent Hubble constant estimate around 70.7 km/s/Mpc.

Quantitative bounds on dark matter and dark energy unification parameters.

Abstract

We use the Markov Chain Monte Carlo method to investigate a global constraints on the modified Chaplygin gas (MCG) model as the unification of dark matter and dark energy from the latest observational data: the Union2 dataset of type supernovae Ia (SNIa), the observational Hubble data (OHD), the cluster X-ray gas mass fraction, the baryon acoustic oscillation (BAO), and the cosmic microwave background (CMB) data. In a flat universe, the constraint results for MCG model are, $\Omega_{b}h^{2}=0.02263^{+0.00184}_{-0.00162}$ ($1\sigma$) $^{+0.00213}_{-0.00195}$ $(2\sigma)$, $B_{s}=0.7788^{+0.0736}_{-0.0723}$ ($1\sigma$) $^{+0.0918}_{-0.0904}$ $(2\sigma)$, $\alpha=0.1079^{+0.3397}_{-0.2539}$ ($1\sigma$) $^{+0.4678}_{-0.2911}$ $(2\sigma)$, $B=0.00189^{+0.00583}_{-0.00756}$ ($1\sigma$) $^{+0.00660}_{-0.00915}$ $(2\sigma)$, and $H_{0}=70.711^{+4.188}_{-3.142}$ ($1\sigma$) $^{+5.281}_{-4.149}$ $(2\sigma)$.