Magnetic stability of massive star forming clumps in RCW 106

Abstract

The RCW 106 molecular cloud complex is an active massive star-forming region where a ministarburst is taking place. We examined its magnetic structure by near-IR polarimetric observations with the imaging polarimeter SIRPOL on the IRSF 1.4 m telescope. The global magnetic field is nearly parallel to the direction of the Galactic plane and the cloud elongation. We derived the magnetic field strength of $\sim 100$-$1600\mu$G for 71 clumps with the Davis-Chandrasekhar-Fermi method. We also evaluated the magnetic stability of these clumps and found massive star-forming clumps tend to be magnetically unstable and gravitationally unstable. Therefore, we propose a new criterion to search for massive star-forming clumps. These details suggest that the process enhancing the clump density without an increase of the magnetic flux is essential for the formation of massive stars and the necessity for accreting mass along the magnetic field lines.

14 pages, 4 figures, accepted to ApJL

References in corpus (8)

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Cited by in corpus (2)

• The Role of Magnetic Fields in Triggered Star Formation of RCW 120
• High-Mass Starless Clumps: Dynamical State and Correlation Between Physical Parameters