Mass–size diagram of the cores detected in the simulated Herschel images. The red line represents half of the critical Bonnor-Ebert mass (M_BE/2) at 10 K as a function of radius. The blue line shows the empirical threshold used to select candidate prestellar cores in Sect. 3.2 (cf. Fig. 4), which captures 95% of the synthetic prestellar cores in the simulation. The curves labeled R_BES (in magenta) show the mass vs. radius relations for the convolved model cores, while the lines labeled R_AS (in green) represent the true mass vs. radius relations of the models. The black dashed vertical line shows the minimum derived model size (MMS) used when applying simple Gaussian deconvolution to the simulated extraction results (see Sect. 3.2).