Observational Constraints of Modified Chaplygin Gas in RS II Brane

TL;DR

This paper investigates the constraints on a modified Chaplygin gas model within the RS II brane framework using observational data, deriving parameter bounds and confirming consistency with supernova and cosmological observations.

Contribution

It provides observational bounds on the parameters of the modified Chaplygin gas model in RS II brane cosmology using multiple astrophysical data sets.

Findings

Parameter bounds obtained at various confidence levels.

Model fits well with supernova data.

Consistent with cosmological observations.

Abstract

FRW universe in RS II braneworld model filled with a combination of dark matter and dark energy in the form of modified Chaplygin gas (MCG) is considered. It is known that the equation of state (EoS) for MCG is a three-variable equation determined by $A$, $\alpha$ and $B$. The permitted values of these parameters are determined by the recent astrophysical and cosmological observational data. Here we present the Hubble parameter in terms of the observable parameters $\Omega_{m0}$, $\Omega_{x0}$, $H_{0}$, redshift $z$ and other parameters like $A$, $B$, $C$ and $\alpha$. From Stern data set (12 points), we have obtained the bounds of the arbitrary parameters by minimizing the $\chi^{2}$ test. The best-fit values of the parameters are obtained by 66%, 90% and 99% confidence levels. Next due to joint analysis with BAO and CMB observations, we have also obtained the bounds of the parameters ($B,C$) by fixing some other parameters $\alpha$ and $A$. The best fit value of distance modulus $\mu(z)$ is obtained for the MCG model in RS II brane, and it is concluded that our model is perfectly consistent with the union2 sample data.