Correlation between ¹²CO brightness temperature at a distance of 10 au from the central star and stellar luminosity. The values of T_b,10 and log₁₀(L_*) were taken from Tables A.1 and A.2 and Empey et al., in prep., respectively. The values of T_b,10 were converted from cylindrical coordinates to spherical coordinates using the vertical-height-profile values reported in Table A.1. The values of F_cont were taken from Carpenter et al. (2025).