Exploring the H0 tension and the evidence for dark sector interactions from 2D BAO measurements

We explore observational constraints on a cosmological model with an interaction between dark energy (DE) and dark matter (DM), using a compilation of 15 measurements of the 2D baryon acoustic oscillation (BAO) (i.e., transversal) scale in combination with Planck-CMB data, to explore the parametric space of a class of interacting DE (IDE) models. We find that 2D BAO measurements can generate different observational constraints compared to the traditional approach of studying the matter clustering in the 3D BAO measurements. Contrary to the observations for the ACDM and IDE models when analyzed with Planck-CMB + 3D BAO data, we note that Planck-CMB + 2D BAO data favor high values of the Hubble constant H0. From the joint analysis with Planck-CMB + 2D BAO + Gaussian prior on H0, we find H0 = 73.4 +/- 0.88 km/s/Mpc. We conclude that the H0 tension is solved in the IDE model with strong statistical evidence (more than 3 sigma) for the IDE cosmologies.

Automated summary

In this study, we use a compilation of 15 measurements of the 2D baryon acoustic oscillation (BAO) scale and Planck-CMB data to explore a class of interacting dark energy (DE) and dark matter (DM) cosmological models. We find that 2D BAO measurements can provide different observational constraints compared to the traditional 3D BAO measurements. Contrary to previous observations, Planck-CMB + 2D BAO data suggest higher values for the Hubble constant H0. Through joint analysis with additional Gaussian prior on H0, we conclude that the H0 tension is resolved in the interacting DE model with strong statistical evidence (more than 3 sigma).