Giant Spiraling Molecular Gas Arms As Cradles Of Dense Massive Molecular Cores
A research team led by Dr. Hauyu Liu at the Institute of Astronomy and Astrophysics, Academia Sinica (ASIAA) observed the luminous OB cluster-forming massive molecular clump G33.92+0.11 with the Atacama Large Millimeter/submillimeter Array (ALMA), and unveiled the fine molecular gas structures deeply embedded at the center of the parent molecular cloud. This finding provides a greatly simplified picture of overall cloud geometry and kinematics, which represents a crucial step forward in the understanding of the upper end of the stellar and molecular core mass functions. The research was published in the April 28 issue of The Astrophysical Journal.
Via ALMA observations, this research for the first time resolved an embedded giant coherent dense gas structure on a several light-year scale. Surprisingly, this dense gas structure presents several spiral arms, which appear like a version of the previously observed spiral arms surrounding the low-mass protobinary, scaled-up by a factor of ~103. These giant spiral arms, and the massive molecular gas cores located at their convergence, are cradles to form the highest mass stars in this stellar cluster.