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Title: Massive Protostars in a Protocluster—A Multi-scale ALMA View of G35.20-0.74N
Abstract We present a detailed study of the massive star-forming region G35.2-0.74N with Atacama Large Millimeter/submillimeter Array (ALMA) 1.3 mm multi-configuration observations. At 0.″2 (440 au) resolution, the continuum emission reveals several dense cores along a filamentary structure, consistent with previous ALMA 0.85 mm observations. At 0.″03 (66 au) resolution, we detect 22 compact sources, most of which are associated with the filament. Four of the sources are associated with compact centimeter continuum emission, and two of these are associated with H30αrecombination line emission. The H30αline kinematics shows the ordered motion of the ionized gas, consistent with disk rotation and/or outflow expansion. We construct models of photoionized regions to simultaneously fit the multiwavelength free–free fluxes and the H30αtotal fluxes. The derived properties suggest the presence of at least three massive young stars with nascent hypercompact Hiiregions. Two of these ionized regions are surrounded by a large rotating structure that feeds two individual disks, revealed by dense gas tracers, such as SO2, H2CO, and CH3OH. In particular, the SO2emission highlights two spiral structures in one of the disks and probes the faster-rotating inner disks. The12CO emission from the general region reveals a complex outflow structure, with at least four outflows identified. The remaining 18 compact sources are expected to be associated with lower-mass protostars forming in the vicinity of the massive stars. We find potential evidence for disk disruption due to dynamic interactions in the inner region of this protocluster. The spatial distribution of the sources suggests a smooth overall radial density gradient without subclustering, but with tentative evidence of primordial mass segregation.  more » « less
Award ID(s):
2206450
PAR ID:
10559042
Author(s) / Creator(s):
; ; ; ; ; ; ; ; ; ;
Publisher / Repository:
AAS/IOP
Date Published:
Journal Name:
The Astrophysical Journal
Volume:
936
Issue:
1
ISSN:
0004-637X
Page Range / eLocation ID:
68
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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