Constraints on accelerating universe using ESSENCE and Gold supernovae data combined with other cosmological probes

TL;DR

This paper combines multiple cosmological data sets, including supernovae, CMB, BAO, and galaxy cluster data, to constrain models of the accelerating universe and compare dark energy models.

Contribution

It provides new combined constraints on cosmological parameters and dark energy models using recent observational data sets.

Findings

Transition redshift z_T ≈ 0.63 with uncertainties.

Lower matter density Ω_0m and current deceleration q_0 from combined data.

Equal support for ΛCDM and two dark energy parameterizations.

Abstract

We use recently observed data: the 192 ESSENCE type Ia supernovae (SNe Ia), the 182 Gold SNe Ia, the 3-year WMAP, the SDSS baryon acoustic peak, the X-ray gas mass fraction in clusters and the observational $H(z)$ data to constrain models of the accelerating universe. Combining the 192 ESSENCE data with the observational $H(z)$ data to constrain a parameterized deceleration parameter, we obtain the best fit values of transition redshift and current deceleration parameter $z_{T}=0.632^{+0.256}_{-0.127}$, $q_{0}=-0.788^{+0.182}_{-0.182}$. Furthermore, using $\Lambda$CDM model and two model-independent equation of state of dark energy, we find that the combined constraint from the 192 ESSENCE data and other four cosmological observations gives smaller values of $\Omega_{0m}$ and $q_{0}$, but a larger value of $z_{T}$ than the combined constraint from the 182 Gold data with other four observations. Finally, according to the Akaike information criterion it is shown that the recently observed data equally supports three dark energy models: $\Lambda$CDM, $w_{de}(z)=w_{0}$ and $w_{de}(z)=w_{0}+w_{1}\ln(1+z)$.