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Title: The SOFIA Massive (SOMA) Star Formation Survey. IV. Isolated Protostars
Abstract We present ∼10–40μm SOFIA-FORCAST images of 11isolatedprotostars as part of the SOFIA Massive (SOMA) Star Formation Survey, with this morphological classification based on 37μm imaging. We develop an automated method to define source aperture size using the gradient of its background-subtracted enclosed flux and apply this to build spectral energy distributions (SEDs). We fit the SEDs with radiative transfer models, developed within the framework of turbulent core accretion (TCA) theory, to estimate key protostellar properties. Here, we release the sedcreator python package that carries out these methods. The SEDs are generally well fitted by the TCA models, from which we infer initial core massesMcranging from 20–430M⊙, clump mass surface densities Σcl∼ 0.3–1.7 g cm−2, and current protostellar massesm*∼ 3–50M⊙. From a uniform analysis of the 40 sources in the full SOMA survey to date, we find that massive protostars form across a wide range of clump mass surface density environments, placing constraints on theories that predict a minimum threshold Σclfor massive star formation. However, the upper end of them*−Σcldistribution follows trends predicted by models of internal protostellar feedback that find greater star formation efficiency in higher Σclconditions. We also investigate protostellar far-IR variability by comparison with IRAS data, finding no significant variation over an ∼40 yr baseline.  more » « less
Award ID(s):
2206450
PAR ID:
10388093
Author(s) / Creator(s):
; ; ; ; ; ; ; ; ; ; ; ; ; ; ;
Publisher / Repository:
DOI PREFIX: 10.3847
Date Published:
Journal Name:
The Astrophysical Journal
Volume:
942
Issue:
1
ISSN:
0004-637X
Format(s):
Medium: X Size: Article No. 7
Size(s):
Article No. 7
Sponsoring Org:
National Science Foundation
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