Mass-size diagram for the cores identified in the California molecular cloud. “Extraction” represents the sizes measured directly on the 18.2″ column density map. “Decon. Robust”, “Decon. Candidate”, and “Decon. Unbound” represent the sizes of robust prestellar, candidate prestellar, and unbound starless cores, respectively, after deconvolution. The red solid line represents half of the mass of a thermally critical Bonnor-Ebert sphere (M_BE/2) of radius R at a temperature of 10 K. The blue solid line marks the estimated threshold for selecting candidate prestellar cores. The dashed vertical line marks the 18.2″ beam size.