The SOFIA Massive (SOMA) Star Formation Survey. IV. Isolated Protostars
Journal article, 2023
We present similar to 10-40 mu m SOFIA-FORCAST images of 11 isolated protostars as part of the SOFIA Massive (SOMA) Star Formation Survey, with this morphological classification based on 37 mu m 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 masses M ( c ) ranging from 20-430 M (circle dot), clump mass surface densities sigma(cl) similar to 0.3-1.7 g cm(-2), and current protostellar masses m (*) similar to 3-50 M (circle dot). 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 sigma(cl) for massive star formation. However, the upper end of the m (*)-sigma(cl) distribution follows trends predicted by models of internal protostellar feedback that find greater star formation efficiency in higher sigma(cl) conditions. We also investigate protostellar far-IR variability by comparison with IRAS data, finding no significant variation over an similar to 40 yr baseline.
Author
Rubén Fedriani
Chalmers, Space, Earth and Environment, Astronomy and Plasmaphysics
Jonathan Tan
Chalmers, Space, Earth and Environment, Astronomy and Plasmaphysics
Zoie Telkamp
University of Virginia
Yichen Zhang
RIKEN
University of Virginia
Yao-Lun Yang
University of Virginia
RIKEN
Mengyao Liu
University of Virginia
James M. De Buizer
NASA Ames Research Center
Chi Yan Law
Chalmers, Space, Earth and Environment, Astronomy and Plasmaphysics
Maria T. Beltran
Istituto nazionale di astrofisica (INAF)
Viviana Rosero
National Radio Astronomy Observatory Socorro
Tanaka
University of Colorado at Boulder
National Institutes of Natural Sciences
Giuliana Cosentino
Chalmers, Space, Earth and Environment, Astronomy and Plasmaphysics
Prasanta Gorai
Chalmers, Space, Earth and Environment, Astronomy and Plasmaphysics
Juan Pablo Farias Osses
Chalmers, Space, Earth and Environment, Astronomy and Plasmaphysics
Jan E. Staff
University of The Virgin Islands
Barbara Whitney
Space Science Institute
Astrophysical Journal
0004-637X (ISSN) 1538-4357 (eISSN)
Vol. 942 1 7Subject Categories
Astronomy, Astrophysics and Cosmology
DOI
10.3847/1538-4357/aca4cf