Disks and outflows in the S255IR area of high mass star formation from ALMA observations

Abstract

We describe the general structure of the well known S255IR high mass star forming region, as revealed by our recent ALMA observations. The data indicate a physical relation exists between the major clumps SMA1 and SMA2. The driving source of the extended high velocity, well collimated bipolar outflow, is not the most pronounced disk-like SMA1 clump harboring a 20 M o young star (S255 NIRS3), as was assumed earlier. Apparently, it is the less evolved SMA2 clump, which drives the outflow and contains a compact rotating structure (probably a disk). At the same time, the SMA1 clump drives another outflow, with a larger opening angle. The molecular line data do not show an outflow from the SMA3 clump (NIRS1), which was suggested by IR studies of this region.