Mass-radius posterior distributions showing the 2D histogram for the PP (left panel) and CS (right panel) extensions with Bayesian χEFT uncertainties up to 1.5n₀ with pQCD extensions (GP-N³LO with pQCD extension, upper panels) and uniformly sampled in the previous N³LO range (N³LO, lower panels). The dark shaded hexagons indicate a lower number of mass–radius samples, while the lighter shaded hexagons indicate a higher number of mass–radius samples. The insets show the radius distribution for a 1.4 M_⊙ star, indicated by the black dashed lines.