Model-independent breaking of the baryon-dark matter degeneracy

Abstract

The adoption of a model-indpendent approach to reconstruct the Hubble rate [Formula: see text] through Bézier polynomials helps alleviate the baryon-dark matter degeneracy when intermediate-[Formula: see text] data are adopted. This is achieved by employing model-independent angular-diameter distances inferred through the Sunyaev-Zeldovich effect. Then, using correlated baryonic acoustic oscillation data permits us to do not fix the baryon density [Formula: see text] enabling the breaking of the matter sector degeneracy and getting constraints on [Formula: see text] and on the total matter density [Formula: see text]. The constraints on all involved parameters are determined adopting a Monte-Carlo Markov chain analysis showing a [Formula: see text]-[Formula: see text] agreement with the [Formula: see text]CDM model and roughly when the curvature is involved. Finally, in view of the Hubble tension our results slightly match late-time constraints on [Formula: see text].