The SOFIA Massive (SOMA) Star Formation Survey - Tests of Massive Star Formation Theories

We present an overview and latest results of the SOFIA Massive (SOMA) star formation survey, which aims to build up a sample of ~50 high- and intermediate-mass protostars in a range of different environments that are observed with SOFIA-FORCAST from ~10 to 40 μm to test theoretical models of massive star formation. We present multi-wavelength images and build their spectral energy distributions (SEDs) together with archival Spitzer and Herschel data and other ground-based IR data. Radiative transfer (RT) models of Zhang & Tan (2018), based on the Turbulent Core Accretion theory, are then fit to the SEDs to estimate key properties of the protostars such as stellar mass, the initial core mass, clump mass surface density and accretion rate. The sources analyzed so far span a luminosity range of 10 ³ -10 ⁶ L⊙, with masses from intermediate to high values, and their environments from isolated to clustered. Source morphologies at MIR to FIR wavelengths appear to be influenced by outflow cavities and extinction from dense gas surrounding the protostars. From the best fit models of the most luminous protostars, we do not see any evidence that Σ _cl needs to be high to form these massive stars.