Testing cosmological models with isotropic and anisotropic components of BAO data [CEA]


We conduct a selective analysis of the isotropic ($D_V$) and anisotropic ($AP$) components of the Baryon Acoustic Oscillations (BAO) data. We find that these components provide significantly different constraints and could provide strong diagnostics for model selection, also in view of more precise data to arrive. We complemented the BAO data with the Supernova Ia (SNIa) and Observational \textit{Hubble} datasets to perform a joint analysis on the $\Lambda$CDM model and its standard extensions. From this analysis, we find a value of $H_0 = 69.4 \pm 1.7$ \text{Km/s Mpc$^{-1} $} in the $\Lambda$CDM scenario, which is now consistent with both the Planck and the direct estimates of Riess et al. We also comment on the possible bias on $H_0$ estimates introduced by approximate formulae for the sound horizon at drag epoch ($r_d$). We find that the evidence for acceleration using the BAO data alone is more than $\sim 5.8\sigma$, which increases to $8.4 \sigma$ in our joint analysis. Using the BAO data alone, we find a $2.2 \sigma$ deviation from the concordance model in a two-parameter extension of $\Lambda$CDM, where both $\Omega_k$ and $w$ are considered as free parameters, leaving space for new physics.

Read this paper on arXiv…

B. Haridasu, V. Lukovic and N. Vittorio
Mon, 13 Nov 17

Comments: 9 pages, 7 figures, submitted to A&A