Constraints on Kinematic Model from Recent Cosmic Observations: SN Ia, BAO and Observational Hubble Data

TL;DR

This study compares three parameterized models of cosmic expansion using SN Ia, BAO, and Hubble data, finding all predict current acceleration and a transition from deceleration, with models $M_1$ and $M_2$ aligning with $\\Lambda$CDM.

Contribution

It evaluates three different kinematic models against recent cosmic observations, highlighting their compatibility with $\\Lambda$CDM and constraining transition redshifts.

Findings

All models predict current accelerated expansion.

Models $M_1$ and $M_2$ are compatible with $\\Lambda$CDM.

Transition redshift varies between 0.6 and 1.

Abstract

In this paper, linear first order expansion of deceleration parameter $q(z)=q_0+q_1(1-a)$ ($M_1$), constant jerk $j=j_0$ ($M_2$) and third order expansion of luminosity distance ($M_3$) are confronted with cosmic observations: SCP 307 SN Ia, BAO and observational Hubble data (OHD). Likelihood is implemented to find the best fit model parameters. All these models give the same prediction of the evolution of the universe which is undergoing accelerated expansion currently and experiences a transition from decelerated expansion to accelerated expansion. But, the transition redshift depends on the concrete parameterized form of the model assumed. $M_1$ and $M_2$ give value of transition redshift about $z_t\sim 0.6$. $M_3$ gives a larger one, say $z_t\sim 1$. The $\chi^2/dof$ implies almost the same goodness of the models. But, for its badness of evolution of deceleration parameter at high redshift $z>1$, $M_3$ can not be reliable. $M_1$ and $M_2$ are compatible with $\Lambda$CDM model at the $2\sigma$ and $1\sigma$ confidence levels respectively. $M_3$ is not compatible with $\Lambda$CDM model at $2\sigma$ confidence level. From $M_1$ and $M_2$ models, one can conclude that the cosmic data favor a cosmological model having $j_0<-1$.