The ALMA Survey of 70 mu m Dark High-mass Clumps in Early Stages (ASHES). III. A Young Molecular Outflow Driven by a Decelerating Jet
Journal article, 2021
We present a spatio-kinematical analysis of the CO (J = 2 -> 1) line emission, observed with the Atacama Large Millimeter/submillimeter Array (ALMA), of the outflow associated with the most massive core, ALMA1, in the 70 mu m dark clump G010.991-00.082. The position-velocity (PV) diagram of the molecular outflow exhibits a peculiar S-shaped morphology that has not been seen in any other star-forming region. We propose a spatio-kinematical model for the bipolar molecular outflow that consists of a decelerating high-velocity component surrounded by a slower component whose velocity increases with distance from the central source. The physical interpretation of the model is in terms of a jet that decelerates as it entrains material from the ambient medium, which has been predicted by calculations and numerical simulations of molecular outflows in the past. One side of the outflow is shorter and shows a stronger deceleration, suggesting that the medium through which the jet moves is significantly inhomogeneous. The age of the outflow is estimated to be tau approximate to 1300 yr, after correction for a mean inclination of the system of approximate to 57 degrees.
Author
Daniel Tafoya
Chalmers, Space, Earth and Environment, Onsala Space Observatory
Patricio Sanhueza
National Institutes of Natural Sciences
The Graduate University for Advanced Studies (SOKENDAI)
Qizhou Zhang
Harvard-Smithsonian Center for Astrophysics
Shanghuo Li
Chinese Academy of Sciences
Harvard-Smithsonian Center for Astrophysics
Andres E. Guzman
National Institutes of Natural Sciences
Andrea Silva
National Institutes of Natural Sciences
Eduardo de la Fuente
University of Guadalajara
Xing Lu
National Institutes of Natural Sciences
Kaho Morii
University of Tokyo
National Institutes of Natural Sciences
Ken'ichi Tatematsu
National Institutes of Natural Sciences
Yanett Contreras
Leiden University
Natsuko Izumi
Ibaraki University
National Institutes of Natural Sciences
James M. Jackson
NASA Ames Research Center
Fumitaka Nakamura
The Graduate University for Advanced Studies (SOKENDAI)
National Institutes of Natural Sciences
Takeshi Sakai
University of Electro-Communications
Astrophysical Journal
0004-637X (ISSN) 1538-4357 (eISSN)
Vol. 913 2 131Subject Categories
Astronomy, Astrophysics and Cosmology
Geophysics
Fluid Mechanics and Acoustics
DOI
10.3847/1538-4357/abf5da