Posterior probability distributions of the mass, radius and water mass fraction (WMF) derived from in the interior structure retrieval. The diagonal panels show the marginalized probability distributions of the individual parameters. For the observable parameters (mass and radius), the mean observed value is indicated with a black line. The mean and the 1σ interval of the posterior distributions retrieved in the MCMC are shown as orange dashed lines for all parameters. The PDFs agree well with the mean and uncertainties of the observed mass and radius.