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Title: Fragmentation of the High-mass “Starless” Core G10.21-0.31: A Coherent Evolutionary Picture for Star Formation
Abstract G10.21-0.31 is a 70 μ m dark high-mass starless core ( M > 300 M ⊙ within r < 0.15 pc) identified in the Spitzer, Herschel, and APEX continuum surveys, and is believed to harbor the initial stages of high-mass star formation. We present Atacama Large Millimeter/submillimeter Array (ALMA) and Submillimeter Array observations to resolve the internal structure of this promising high-mass starless core. Sensitive high-resolution ALMA 1.3 mm dust continuum emission reveals three cores of mass ranging within 11–18 M ⊙ , characterized by a turbulent fragmentation. Cores 1, 2, and 3 represent a coherent evolution of three different stages, characterized by outflows (CO and SiO), gas temperature (H 2 CO), and deuteration (N 2 D + /N 2 H + ). We confirm the potential for formation of high-mass stars in G10.21 and explore the evolution path of high-mass star formation. Yet, no high-mass prestellar core is present in G10.21. This suggests a dynamical star formation where cores grow in mass over time.  more » « less
Award ID(s):
2309542 2108989 2309536
PAR ID:
10436893
Author(s) / Creator(s):
; ; ; ; ;
Date Published:
Journal Name:
The Astrophysical Journal
Volume:
945
Issue:
1
ISSN:
0004-637X
Page Range / eLocation ID:
81
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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