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arXiv · 1701.05953

Zooming in to Massive Star Birth

Shuo Kong·Jonathan C. Tan·Paola Caselli·Francesco Fontani·Ke Wang·Michael J. Butler
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Abstract

We present high resolution (0.2", 1000 AU) 1.3 mm ALMA observations of massive infrared dark cloud clump, G028.37+00.07-C1, thought to harbor the early stages of massive star formation. Using $\rm N_2D^+$(3-2) we resolve the previously identified C1-S core, separating the bulk of its emission from two nearby protostellar sources. C1-S is thus identified as a massive ($\sim50\:M_\odot$), compact ($\sim0.1\:$pc diameter) starless core, e.g., with no signs of outflow activity. Being highly deuterated, this is a promising candidate for a pre-stellar core on the verge of collapse. An analysis of its dynamical state indicates a sub-virial velocity dispersion compared to a trans-Alfv\'enic turbulent core model. However, virial equilibrium could be achieved with sub-Alfv\'enic conditions involving $\sim2\:$mG magnetic field strengths.

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Shuo Kong, Jonathan C. Tan, Paola Caselli, Francesco Fontani, Ke Wang, Michael J. Butler. 2017-01-21. Zooming in to Massive Star Birth. https://doi.org/10.3847/1538-4357%2Faae1b2

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