Asteroseismic mass as a function of the asteroseismic radius, with an indication of the evolutionary status derived from the mixed-mode spacing: blue squares for RGB stars, red diamonds for clump stars. Stars without clear measurement of ΔT_obs are marked with a small cross. The rectangle indicates the mean 1-σ error bars. The dotted lines at 1 and 1.8   M_⊙ correspond to the limits defined in the text.