Mass versus size diagram for the entire population of starless cores. The core sizes were estimated from the geometrical average between the major and minor FWHM measured by getsources in the high-resolution column density map and deconvolved from the 18.′′ 2 HPBW resolution of the map. The 18.′′2 resolution at the distance of 150 pc is indicated by the dashed line. Candidate prestellar cores are plotted with circular symbols and unbound cores with crosses. Colours indicate cores from the three regions: Lupus I (black), Lupus III (red), Lupus IV (green). The solid line indicates the virial criterion (M_BE,crit∕M_obs = 2), assuming T = 11 K and d = 150 pc; cores above this line are considered robust candidate prestellar cores.