Ammonia and CO Outflow around 6.7 GHz Methanol Masers

Abstract

Single point observations are presented in NH3 (1,1) and (2,2) inversion transitions using the Effelsberg 100 m telescope for a sample of 100 6.7 GHz methanol masers and mapping observations in the 12CO and 13CO (1-0) transitions using the PMO Delingha 13.7 m telescope for 82 sample sources with detected ammonia. A further 62 sources were selected for either 12CO or 13CO line outflow identification, producing 45 outflow candidates, 29 using 12CO and 16 using 13CO data. Twenty-two of the outflow candidates were newly identified, and 23 had trigonometric parallax distances. Physical properties were derived from ammonia lines and CO outflow parameters calculated. Histograms and statistical correlations for ammonia, CO outflow parameters, and 6.7 GHz methanol maser luminosities are also presented. No significant correlation was found between ammonia and maser luminosity. However, weak correlations were found between outflow properties and maser luminosities, which may indicate that outflows are physically associated with 6.7 GHz masers.

41 pages, 11 figures, accepted for publication in AJ

References in corpus (6)

• Trigonometric Parallaxes of Massive Star Forming Regions: VI. Galactic Structure, Fundamental Parameters and Non-Circular Motions
• Methanol Maser Associated Outflows: Detection statistics and properties
• The Arecibo Methanol Maser Galactic Plane Survey - II: Statistical and Multi-wavelength Counterpart Analysis
• Molecular outflows around high-mass young stellar objects
• 6.7GHz Methanol Maser Associated Outflows: An evolutionary sequence
• Detection of 6.7 GHz methanol absorption towards hot corinos

Cited by in corpus (11)

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• Observations of Cyanopolyynes toward Four High-Mass Star-Forming Regions Containing Hot Cores
• Searching for Molecular Outflows with Support Vector Machines: Dark Cloud Complex in Cygnus
• Deuterated ammonia in Galactic massive star-forming regions
• Carbon Chain Chemistry in Hot-Core Regions around Three Massive Young Stellar Objects Associated with 6.7 GHz Methanol Masers
• High-sensitivity millimeter imaging of molecular outflows in nine nearby high-mass star-forming regions
• Orientation effect on the ligh curve shape of periodic methanol maser sources
• Studying star-forming processes at core and clump scales: the case of the young stellar object G29.862-0.0044
• A Possible Chemical Clock in High-mass Star-forming Regions: N(HC3N)/N(N2H+)?
• Cyanopolyyne line survey towards high-mass star-forming regions with TMRT
• Extended Ionized Fe Objects in the UWIFE Survey