An Ordered Envelope-Disk Transition in the Massive Protostellar Source G339.88-1.26

Abstract

© 2019. The American Astronomical Society.. We report molecular line observations of the massive protostellar source G339.88-1.26 with the Atacama Large Millimeter/Submillimeter Array. The observations reveal a highly collimated SiO jet extending from the 1.3 mm continuum source, which connects to a slightly wider but still highly collimated CO outflow. Rotational features perpendicular to the outflow axis are detected in various molecular emissions, including SiO, SO 2 , H 2 S, CH 3 OH, and H 2 CO emissions. Based on their spatial distributions and kinematics, we find that they trace different parts of the envelope-disk system. The SiO emission traces the disk and inner envelope in addition to the jet. The CH 3 OH and H 2 CO emissions mostly trace the infalling-rotating envelope and are enhanced around the transition region between envelope and disk, i.e., the centrifugal barrier. The SO 2 and H 2 S emissions are enhanced around the centrifugal barrier and also trace the outer part of