Observational Constraints of New Variable Modified Chaplygin Gas Model

TL;DR

This paper investigates the observational viability of the New Variable Modified Chaplygin Gas model as dark energy in a flat universe, fitting model parameters using recent data from Hubble, BAO, and CMB observations.

Contribution

It provides a new analysis of the NVMCG model's parameters using recent observational data and combines multiple datasets for comprehensive constraints.

Findings

Best-fit parameter ranges for A_0 and B_0 identified.

Model's distance modulus curve matches observational data.

Constraints at 66%, 90%, and 99% confidence levels obtained.

Abstract

Assuming the flat FRW universe in Einstein's gravity filled with New Variable Modified Chaplygin gas (NVMCG) dark energy and dark matter having negligible pressure. In this research work we analyze the viability on the basis of recent observation. Hubble parameter $H$ is expressed in terms of the observable parameters $H_0$, $\Omega_m^0$ and the model parameters $A_0$, $B_0$, $C_0$, $m$, $n$, $\alpha$ and the red shift parameter $z$. Here we find a best fitted parameter range of $A_0$, $B_0$ keeping $0\leq \alpha \leq 1$ and using Stern data set (12 points) by minimizing the $\chi^2$ test at 66%, 90% and 99% confidence levels. Next we do the joint analysis with BAO and CMB observations. Again evaluating the distance modulus $\mu(z)$ vs redshift ($z$) curve obtained in the model NVMCG with dark matter with the best fitted value of the parameters and comparing with that derived from the union2 compilation data.