Testing Late Time Cosmic Acceleration with uncorrelated Baryon Acoustic Oscillations dataset

TL;DR

This study uses uncorrelated BAO measurements combined with other cosmological data to constrain parameters of the standard and extended cosmological models, supporting late-time cosmic acceleration.

Contribution

It provides new constraints on cosmological parameters using a large, uncorrelated BAO dataset and compares multiple cosmological models with model selection.

Findings

Lambda CDM model fits the data well.

Measured Hubble constant: 69.85 km/sec/Mpc.

Spatial curvature and dark energy equation of state are constrained.

Abstract

Baryon Acoustic Oscillations (BAO) involve measuring the spatial distribution of galaxies to determine the growth rate of cosmic structure. We derive constraints on cosmological parameters from $17$ uncorrelated BAO measurements that were collected from $333$ published data points in the effective redshift range $0.106 \leq z \leq 2.36$. We test the correlation of the subset using random covariance matrix. The $\Lambda$CDM model fit yields the cosmological parameters: $\Omega_m = 0.261 \pm 0.028$ and $\Omega_\Lambda = 0.733 \pm 0.021$. Combining the BAO data with the Cosmic Chronometers data, the Pantheon Type Ia supernova and the Hubble Diagram of Gamma Ray Bursts and Quasars, the Hubble constant yields $ 69.85 \pm 1.27 km/sec/Mpc$ and the sound horizon distance gives: $ 146.1 \pm 2.15 Mpc$. Beyond the $\Lambda$CDM model we test $\Omega_K$CDM and wCDM. The spatial curvature is $\Omega_k = -0.076 \pm 0.012$ and the dark energy equation of states: $w = -0.989 \pm 0.049$. {We perform AIC test to compare the 3 models and see that $\Lambda$CDM scores best.