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arXiv · 2009.10701

Testing Late Time Cosmic Acceleration with uncorrelated Baryon Acoustic Oscillations dataset

David Benisty·Denitsa Staicova
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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 $Λ$CDM model fit yields the cosmological parameters: $Ω_m = 0.261 \pm 0.028$ and $Ω_Λ= 0.733 \pm 0.021$. 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 $Λ$CDM model we test $Ω_K$CDM and wCDM. The spatial curvature is $Ω_k = -0.076 \pm 0.012$ 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 $Λ$CDM scores best.

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David Benisty, Denitsa Staicova. 2020-12-15. Testing Late Time Cosmic Acceleration with uncorrelated Baryon Acoustic Oscillations dataset. https://doi.org/10.1051/0004-6361%2F202039502

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