Molecular outflows around high-mass young stellar objects

Abstract

We present a study of molecular outflows using high-resolution mapping of the CO (1-0) line emission toward eight relatively nearby 6.7 GHz methanol masers, which are associated with massive star forming regions. Outflows were detected in seven out of eight sources, and five of them clearly show bipolar or multiple outflow morphologies. These outflows have typical masses of a few solar masses, momenta of tens of $M_{\odot }$ km s${}^{-1}$, kinetic energies of $\sim$ 10${}^{45}$ ergs, and the mass entrainment rate of a few $10^{-5}{M}_{\odot }$ yr${}^{-1}$. They have significantly more mass and kinetic energy than their low-mass counterparts. In some of the sources, the massive outflow is obviously associated with a particular massive star in the cluster, while in others the origin remains uncertain. The high detection rate of outflows toward methanol masers suggests that the outflow phase of massive protostars encompasses the methanol maser phase.

16 pages, 3 figures, To appear in AJ (July 2006)

References in corpus (3)

• Massive molecular outflows
• Water Masers Toward Ultracompact HII Regions
• The structure of Onsala 1 star forming region

Cited by in corpus (22)

• ON the Nature of the Local Spiral Arm of the Milky Way
• Herschel/HIFI observations of [CII] and [13CII] in PDRs
• Magnetic fields in massive star forming regions
• A Search for Infall Evidence in EGOs I: the Northern Sample
• Methanol Maser Associated Outflows: Detection statistics and properties
• A multiwavelength study of embedded clusters in W5-east, NGC7538, S235, S252 and S254-S258
• Herschel / HIFI observations of CO, H2O and NH3 in Mon R2
• Unveiling the nature and interaction of the intermediate/high-mass YSOs in IRAS 20343+4129
• The SEDIGISM survey: a search for molecular outflows
• EVN observations of 6.7 GHz methanol maser polarization in massive star-forming regions III. The flux-limited sample
• Deeply embedded objects and shocked molecular hydrogen: The environment of the FU Orionis stars RNO 1B/1C
• Kinematics of the ionized-to-neutral interfaces in Monoceros R2
• Ammonia and CO Outflow around 6.7 GHz Methanol Masers
• VLBI Observations of Water Masers in Onsala 1: Massive Binary Star Forming Site?
• Molecular environs and triggered star formation around the large Galactic infrared bubble N 24
• Principal component analysis for estimating parameters of the L1287 dense core by fitting model spectral maps into observed ones
• Multi-frequency Studies of Massive Cores with Complex Spatial and Kinematic Structures
• High-sensitivity millimeter imaging of molecular outflows in nine nearby high-mass star-forming regions
• Multiwavelength study of low-luminosity 6.7-GHz methanol masers
• OH maser toward IRAS 06056+2131: polarization parameters and evolution status
• A multiwavelength study of massive star-forming region IRAS 22506+5944
• Search for High-Mass Protostellar Objects in Cold IRAS Sources