The unprecedented angular resolution and sensitivity of the Atacama Large Millimeter/submillimeter Array make it possible to unveil disk populations in distant (>2 kpc), embedded young cluster environments. We have conducted an observation toward the central region of the massive protocluster G286.21+0.16 at 1.3 mm. With a spatial resolution of 23 mas and a sensitivity of 15
Characterizing the physical conditions at disk scales in class 0 sources is crucial for constraining the protostellar accretion process and the initial conditions for planet formation. We use ALMA 1.3 and 3 mm observations to investigate the physical conditions of the dust around the class 0 binary IRAS 16293–2422 A down to ∼10 au scales. The circumbinary material’s spectral index,
- Publication Date:
- NSF-PAR ID:
- 10385794
- Journal Name:
- The Astrophysical Journal Letters
- Volume:
- 941
- Issue:
- 2
- Page Range or eLocation-ID:
- Article No. L23
- ISSN:
- 2041-8205
- Publisher:
- DOI PREFIX: 10.3847
- Sponsoring Org:
- National Science Foundation
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Abstract μ Jy beam−1, we detect a total of 38 protostellar disks. These disks have dust masses ranging from about 53 to 1825M ⊕, assuming a dust temperature of 20 K. This sample is not closely associated with previously identified dense cores, as would be expected for disks around Class 0 protostars. Thus, we expect our sample, being flux-limited, to be mainly composed of Class I/flat-spectrum source disks, since these are typically more massive than Class II disks. Furthermore, we find that the distributions of disk masses and radii are statistically indistinguishable from those of the Class I/flat-spectrum objects in the Orion molecular cloud, indicating that similar processes are operating in G286.21+0.16 to regulate disk formation and evolution. The cluster center appears to host a massive protostellar system composed of three sources within 1200 au, including a potential binary with 600 au projected separation. Relative to thismore » -
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