Constraints on a generalized deceleration parameter from cosmic chronometers (1702.04916v2)

Abstract: In this paper, we have proposed a generalized parametrization for the deceleration parameter $q$ in order to study the evolutionary history of the universe. We have shown that the proposed model can reproduce three well known $q$-parametrized models for some specific values of the model parameter $\alpha$. We have used the latest compilation of the Hubble parameter measurements obtained from the cosmic chronometer (CC) method (in combination with the local value of the Hubble constant $H_{0}$) and the Type Ia supernova (SNIa) data to place constraints on the parameters of the model for different values of $\alpha$. We have found that the resulting constraints on the deceleration parameter and the dark energy equation of state support the $\Lambda$CDM model within $1\sigma$ confidence level at the present epoch.