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

Abstract

We present Atacama Large Millimeter/Submillimeter Array (ALMA) 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 HH objects far from the pillars. We find that the masses of the disks+envelopes are about 0.1 M and of the bipolar outflows are between 10 −3 -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 photo-evaporated in 10 4 to 10 5 years by the massive and luminous stars located in the Trumpler 14 cluster. Finally, given the short photo-evaporated 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.

Protostellar outflows: a window to the past

“…Once an outflow bullet leaves the dense core and appears at optical wavelengths, it is referred to as an Herbig-Haro object. Herbig-Haro objects often form parsec-scale long chains (Reipurth, Bally & Devine 1997 ;Reipurth, Devine & Bally 1998 ;Cortes-Rangel et al 2020 ;Ferrero et al 2020 ;Movsessian, Magakian & Dodonov 2021 ). The spacing and kinematics of outflow bullets in such a chain should carry a fossil record of the underlying episodic protostellar accretion history (Bally 2016 ;.…”

Catching the Butterfly and the Homunculus of η Carinae with ALMA

“…Finally, assuming that the CO(3−2) line emission is optically thin and in local thermodynamic equilibrium, we estimate the outflow mass using the following equation (see Cortes-Rangel et al 2020), adapted for the J = 3−2 transition:…”

Deep diving off the `Cosmic Cliffs': previously hidden outflows in NGC 3324 revealed by JWST

“…However, if feedback drives star-forming cores to higher densities, then they may shield their disks for a significant fraction of the planet formation timescale (e.g., Reiter et al 2019Reiter et al , 2020a. Well-studied outflows in high-mass regions like Carina have enabled the first studies of planet-forming disks in feedback-dominated regions (e.g., Mesa-Delgado et al 2016;Cortes-Rangel et al 2020). The new population of jets in NGC 3324 provides a target list to extend these kinds of studies to a broader range of feedback conditions as well as younger and possibly lower-mass sources.…”

“…Low-mass stars in high-mass star-forming regions are prime targets to quantify the impact of external feedback and are of particular interest to understand the impact of feedback on planet formation (e.g., O'dell et al 1993;O'dell & Wen 1994a;Bally et al 1998a,b;Henney & Arthur 1998;Johnstone et al 1998;Henney & O'Dell 1999;Bally et al 2000aBally et al , 2006Eisner & Carpenter 2006;Eisner et al 2008;Mann & Williams 2010;Mann et al 2014;Eisner et al 2016Eisner et al , 2018; see Win-★ E-mail: Megan.Reiter@rice.edu (MR) ter Reiter & Parker 2022 for recent reviews). To date, most observations of the millimeter dust emission from disks around low-mass stars at these distances target jet-driving sources (e.g., Mesa-Delgado et al 2016;Cortes-Rangel et al 2020;Reiter et al 2020a).…”