G30.79~FIR~10: A gravitationally bound infalling high-Mass star forming clump

TL;DR

This study detects and models infalling motions in a high-mass star-forming clump, revealing gravitational collapse driven by magnetic and turbulent forces, with detailed measurements of infall velocity, magnetic field, and mass ratios.

Contribution

It provides new measurements of infall velocity, magnetic field strength, and mass-to-flux ratio, confirming the gravitational collapse state of the clump.

Findings

Infall velocity of 0.5 km/s was measured.

Magnetic field strength refined to 855 micro Gauss.

Clump is in a gravitational collapse state, with super-critical mass-to-flux ratio.

Abstract

Infalling motions were detected and modeled toward this source. A mean infall velocity of 0.5 km/s with an infall mass rate of 5x10^-3 Solar masses per year was obtained. Also, a previously estimated value for the magnetic field strength in the plane of the sky was refined to be 855 micro Gauss which we used to calculate a mass-to-magnetic flux ratio of 1.9, or super-critical. The virial mass from turbulent motions was also calculated finding Mvir=563 solar masses, which gives a ratio of Msubmm/Mvir=5.9. Both values strongly suggest that this clump must be in a state of gravitational collapse.