H0 from cosmic chronometers and Type Ia supernovae, with Gaussian processes and the weighted polynomial regression method

We derive new constraints on the Hubble parameter H₀ using the available data on H(𝓏) from cosmic chronometers (CCH), and the Hubble rate data points from the supernovae of Type Ia (SnIa) of the Pantheon compilation and the Hubble Space Telescope (HST) CANDELS and CLASH Multy-Cycle Treasury (MCT) programs. We employ two alternative techniques, Gaussian Processes (GPs) and the Weighted Polynomial Regression (WPR) method, to reconstruct the Hubble function, determine the derived values of H₀, and compare them with the local HST measurement provided by Riess et al. (2018), H0HST=(73.48±1.66) km/s/Mpc, and with the Planck+ΛCDM value, H0P18=(66.88±0.92) km/s/Mpc,. With GPs we obtain H₀ = (67.99 ± 1.94) km/s/Mpc and with the WPR method H₀ = (68.90 ± 1.96) km/s/Mpc. Both are fully compatible at < 1σ c.l., and also with H0P18. In contrast, they are in ∼ 2σ tension with H0HST.