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1. Disk Wind Feedback from High-mass Protostars. II. The Evolutionary Sequence

   https://doi.org/10.3847/1538-4357/acbd47  

   Staff, Jan E.; Tanaka, Kei E. I.; Ramsey, Jon P.; Zhang, Yichen; Tan, Jonathan C. (April 2023, The Astrophysical Journal)

   Abstract Star formation is ubiquitously associated with the ejection of accretion-powered outflows that carve bipolar cavities through the infalling envelope. This feedback is expected to be important for regulating the efficiency of star formation from a natal prestellar core. These low-extinction outflow cavities greatly affect the appearance of a protostar by allowing the escape of shorter-wavelength photons. Doppler-shifted CO line emission from outflows is also often the most prominent manifestation of deeply embedded early-stage star formation. Here, we present 3D magnetohydrodynamic simulations of a disk wind outflow from a protostar forming from an initially 60M_⊙core embedded in a high-pressure environment typical of massive star-forming regions. We simulate the growth of the protostar fromm_*= 1M_⊙to 26M_⊙over a period of ∼100,000 yr. The outflow quickly excavates a cavity with a half opening angle of ∼10° through the core. This angle remains relatively constant until the star reaches 4M_⊙. It then grows steadily in time, reaching a value of ∼50° by the end of the simulation. We estimate a lower limit to the star formation efficiency (SFE) of 0.43. However, accounting for continued accretion from a massive disk and residual infall envelope, we estimate that the final SFE may be as high as ∼0.7. We examine observable properties of the outflow, especially the evolution of the cavity's opening angle, total mass, and momentum flux, and the velocity distributions of the outflowing gas, and compare with the massive protostars G35.20-0.74N and G339.88-1.26 observed by the Atacama Large Millimeter/submillimeter Array (ALMA), yielding constraints on their intrinsic properties. 

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2. The VLA Nascent Disk and Multiplicity Survey of Perseus Protostars (VANDAM). V. 18 Candidate Disks around Class 0 and I Protostars in the Perseus Molecular Cloud

   https://doi.org/10.3847/1538-4357/aaddf3  

   Segura-Cox, Dominique M.; Looney, Leslie W.; Tobin, John J.; Li, Zhi-Yun; Harris, Robert J.; Sadavoy, Sarah; Dunham, Michael M.; Chandler, Claire; Kratter, Kaitlin; Pérez, Laura; et al (October 2018, The Astrophysical Journal)
3. The VLA/ALMA Nascent Disk and Multiplicity (VANDAM) Survey of Orion Protostars. III. Substructures in Protostellar Disks

   https://doi.org/10.3847/1538-4357/abbad5  

   Sheehan, Patrick D.; Tobin, John J.; Federman, Sam; Megeath, S. Thomas; Looney, Leslie W. (October 2020, The Astrophysical Journal)

   null (Ed.)
4. The VLA/ALMA Nascent Disk and Multiplicity (VANDAM) Survey of Orion Protostars. IV. Unveiling the Embedded Intermediate-Mass Protostar and Disk within OMC2-FIR3/HOPS-370

   https://doi.org/10.3847/1538-4357/abc5bf  

   Tobin, John J.; Sheehan, Patrick D.; Reynolds, Nickalas; Megeath, S. Thomas; Osorio, Mayra; Anglada, Guillem; Díaz-Rodríguez, Ana Karla; Furlan, Elise; Kratter, Kaitlin M.; Offner, Stella S.; et al (December 2020, The Astrophysical Journal)

   null (Ed.)
5. The VLA/ALMA Nascent Disk and Multiplicity (VANDAM) Survey of Orion Protostars. VI. Insights from Radiative Transfer Modeling

   https://doi.org/10.3847/1538-4357/ac574d  

   Sheehan, Patrick D.; Tobin, John J.; Looney, Leslie W.; Megeath, S. Thomas (April 2022, The Astrophysical Journal)

   Abstract We present Markov Chain Monte Carlo radiative transfer modeling of a joint ALMA 345 GHz and spectral energy distribution data set for a sample of 97 protostellar disks from the VLA and ALMA Nascent Disk and Multiplicity Survey of Orion Protostars. From this modeling, we derive disk and envelope properties for each protostar, allowing us to examine the bulk properties of a population of young protostars. We find that disks are small, with a median dust radius of 29.4 − 2.7 + 4.1 au and a median dust mass of 5.8 − 2.7 + 4.6 M ⊕ . We find no statistically significant difference between most properties of Class 0, Class I, and flat-spectrum sources with the exception of envelope dust mass and inclination. The distinction between inclination is an indication that the Class 0/I/flat-spectrum system may be difficult to tie uniquely to the evolutionary state of protostars. When comparing with Class II disk dust masses in Taurus from similar radiative transfer modeling, we further find that the trend of disk dust mass decreasing from Class 0 to Class II disks is no longer present, though it remains unclear whether such a comparison is fair owing to differences in star-forming region and modeling techniques. Moreover, the disks we model are broadly gravitationally stable. Finally, we compare disk masses and radii with simulations of disk formation and find that magnetohydrodynamical effects may be important for reproducing the observed properties of disks. 

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