Stellar properties. Panel a: HR diagram. The three lines are the PMS tracks for the illustrative masses of 1, 2, and 3 M_⊙ . Panel b: stellar mass vs. age diagram derived from the PMS tracks. The average of all categories is shown at the top. The dashed line divides Herbig AeBe + F stars from TTSs (G0-type). The three error bars shown are representative of the whole sample at different age intervals. Panel c: labeled version of the middle diagram. Circles indicate the presence of a cavity imaged with PDI and/or in the millimeter.