SOFIA Observations Reveal a Surprise in Massive Star Formation
Researchers using the airborne Stratospheric Observatory for Infrared Astronomy (SOFIA) have captured the most detailed mid-infrared images yet of a massive star condensing within a dense cocoon of dust and gas. The star is G35.20-0.74, commonly known as G35. It is one of the most massive known protostars and is located relatively close to Earth at a distance of 8,000 light-years. Read more
Title: A candidate circumbinary Keplerian disk in G35.20-0.74 N: A study with ALMA Authors: A. Sanchez-Monge, R. Cesaroni, M.T. Beltran, M.S.N. Kumar, T. Stanke, H. Zinnecker, S. Etoka, D. Galli, C.A. Hummel, L. Moscadelli, T. Preibisch, T. Ratzka, F.F.S. van der Tak, S. Vig, C.M. Walmsley, K.-S. Wang
We report on ALMA observations of continuum and molecular line emission with 0.4" resolution towards the high-mass star forming region G35.20-0.74 N. Two dense cores are detected in typical hot-core tracers, such as CH3CN, which reveal velocity gradients. In one of these cores, the velocity field can be fitted with an almost edge-on Keplerian disk rotating about a central mass of 18 solar masses. This finding is consistent with the results of a recent study of the CO first overtone bandhead emission at 2.3µm towards G35.20-0.74 N. The disk radius and mass are >2500 au and 3 solar masses. To reconcile the observed bolometric luminosity (3x10^4 Lsun) with the estimated stellar mass of 18 solar masses, we propose that the latter is the total mass of a binary system.