A parametric reconstruction of the deceleration parameter [CL]


The present work is based on a parametric reconstruction of the deceleration parameter $q(z)$ in a model for the spatially flat FRW universe filled with dark energy and non- relativistic matter. We have proposed a divergence-free logarithmic parametrization of $q(z)$ to probe the entire evolution history of the universe. Using the SN Ia and Hubble parameter datasets, the constraints on the arbitrary model parameters $q_{0}$ and $q_{1}$ are obtained (within $1\sigma$ and $2\sigma$ confidence limits) by $\chi^{2}$-minimization technique. We have then reconstructed the deceleration parameter, the total EoS parameter $\omega_{tot}$, the jerk parameter and have compared the reconstructed results with the spatially flat $\Lambda$CDM model. It has been found that the behavior of $q(z)$ and $\omega_{tot}$ in our model are very similar (within $1\sigma$ confidence limit) to that of the $\Lambda$CDM model if we consider Type Ia Supernova (SN Ia) dataset only, but the evolutions of $q(z)$ and $\omega_{tot}$ are different as compare to the $\Lambda$CDM model if we add Hubble parameter dataset with the SN Ia dataset. Interestingly, we have found that the present values of $q(z)$ and $\omega_{tot}$ within $1\sigma$ errors for SN Ia+Hubble dataset are in good agreement with the $\Lambda$CDM model. The best-fit model is also found to be in good agreement with the observational Hubble data and the supernova distance modulus data against redshift parameter.

Read this paper on arXiv…

A. Mamon and S. Das
Tue, 25 Oct 16

Comments: 15 pages, 6 figures