ALMA Observations of the Extraordinary Carina Pillars: HH 901/902

Abstract

We present Atacama Large Millimeter/Submillimeter Array 1.3 mm continuum and C 18 O(2−1), N 2 D + (3−2), 13 CS(5−4), and 12 CO(2−1) line sensitive and high angular resolution (∼0.″3) observations of the famous Carina pillars and protostellar objects HH 901/902. Our observations reveal for the first time, the bipolar CO outflows and the dusty disks (plus envelopes) that are energizing the extended and irradiated Herbig–Haro (HH) objects far from the pillars. We find that the masses of the disks+envelopes are about 0.1 M ⊙ and that the bipolar outflows are between 10 −3 and 10 −4 M ⊙ , which suggests that they could be low- or maybe intermediate-mass protostars. Moreover, we suggest that these young low-mass stars are likely embedded Class 0/I protostars with high-accretion rates. We also show the kinematics of the gas in the pillars together with their respective gas masses (0.1–0.2 M ⊙ ). We estimate that the pillars will be photoevaporated in 10 4 to 10 5 yr by the massive and luminous stars located in the Trumpler 14 cluster. Finally, given the short photoevaporated timescales and that the protostars in these pillars are still very embedded, we suggest that the disks inside of the pillars will be quickly affected by the radiation of the massive stars, forming proplyds, like those observed in Orion.