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arXiv · 2002.09293

Cosmological parameter analyses using transversal BAO data

Rafael C. Nunes·Santosh K. Yadav·J. F. Jesus·Armando Bernui
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Abstract

We investigate observational constraints on cosmological parameters combining 15 measurements of the transversal BAO scale (obtained free of any fiducial cosmology) with Planck-CMB data to explore the parametric space of some cosmological models. We investigate how much Planck + transversal BAO data can constraint the minimum $Λ$CDM model, and extensions, including neutrinos mass scale $M_ν$, and the possibility for a dynamical dark energy (DE) scenario. Assuming the $Λ$CDM cosmology, we find $H_0 = 69.23 \pm 0.50$ km s${}^{-1}$ Mpc${}^{-1}$, $M_ν < 0.11$ eV and $r_{\rm drag} = 147.59 \pm 0.26$ Mpc (the sound horizon at drag epoch) from Planck + transversal BAO data. When assuming a dynamical DE cosmology, we find that the inclusion of the BAO data can indeed break the degeneracy of the DE free parameters, improving the constraints on the full parameter space significantly. We note that the model is compatible with local measurements of $H_0$ and there is no tension on $H_0$ estimates in this dynamical DE context. Also, we discuss constraints and consequences from a joint analysis with the local $H_0$ measurement from SH0ES. Finally, we perform a model-independent analysis for the deceleration parameter, $q(z)$, using only information from transversal BAO data.

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Rafael C. Nunes, Santosh K. Yadav, J. F. Jesus, Armando Bernui. 2020-08-07. Cosmological parameter analyses using transversal BAO data. https://doi.org/10.1093/mnras%2Fstaa2036

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