Confirming the Explosive Dispersal Outflow in DR21 with ALMA

Abstract

We present Atacama Large Millimeter/submillimeter Array (ALMA) 1.3 mm continuum and CO(2-1) line emission observations toward the high-mass star formation region DR21. Five new continuum sources are found. We identify eighteen outflow streamers detected in CO emission radially arising from a common origin. The velocity spread of the outflow streamers range between $-$100 to $+$70 km s${}^{-1}$. The radial velocities of each outflow roughly follow linear gradients (Hubble-Lemaitre-like expansion motions). Using the CO emission of the whole ensemble of streamers we estimate a total outflow mass of 120-210M${}_{\odot }$. Additionally, we derived the dynamical age (8600 yr), momentum ($\sim 10^3$ M${}_{\odot }$ km s${}^{-1}$), and kinetic energy ($\sim 10^{48}$ erg) of the outflow. The morphology and kinematics presented by the CO outflow streamers confirm the presence of an explosive dispersal outflow at the heart of DR21. Five dispersal explosive outflows associated with massive star-forming regions have been confirmed in our Galaxy (Orion BN/KL, G5.89-0.39, S106-IR, IRAS16076-5134 and IRAS 12326-6245). However, their frequency of occurrence in the Galaxy and the originating nature are still uncertain.

19 pages, 15 figures including 4 in the appendix, accepted for publication to A&A

References in corpus (13)

• CARMA Large Area Star Formation Survey: Observational Analysis of Filaments in the Serpens South Molecular Cloud
• Monitoring the Large Proper Motions of Radio Sources in the Orion BN/KL Region
• The ALMA View of the OMC1 Explosion in Orion
• The Orion Protostellar Explosion and Runaway Stars Revisited: Stellar Masses, Disk Retention, and an Outflow from BN
• Molecular outflows: Explosive versus protostellar
• Confirming the Explosive Outflow in G5.89 with ALMA
• Outflows, envelopes, and disks as evolutionary indicators in Lupus YSOs
• Possible Explosive Dispersal Outflow in IRAS 16076-5134 revealed with ALMA
• The Cygnus Allscale Survey of Chemistry and Dynamical Environments: CASCADE. II. A detailed kinematic analysis of the DR21 Main outflow
• ATLASGAL-selected high-mass clumps in the inner Galaxy. VII. Characterisation of mid-J CO emission
• An orbital release model for the Orion BN/KL fingers
• Modelling the CO streamers in the explosive ejection of Orion BN/KL region
• Episodicity in accretion-ejection processes associated with IRAS 15398-3359

Cited by in corpus (1)

• SOFIA FIFI-LS spectroscopy of DR21 Main: energetics of the spatially-resolved outflow from a high-mass protostar