A 6.7 GHz methanol maser survey of the central molecular zone

Abstract

The Central Molecular Zone (CMZ) spans the inner ~450 pc (3 degrees) of our Galaxy. This region is defined by its enhanced molecular emission and contains 5% of the entire Galaxy's molecular gas mass. However, the number of detected star forming sites towards the CMZ may be low for the amount of molecular gas that is present, and improved surveys of star formation indicators can help clarify this. With the Karl G Jansky Very Large Array (VLA), we conducted a blind survey of 6.7 GHz methanol masers spanning the inner 3deg x 40arcmin (450 pc x 100 pc) of the Galaxy. We detected 43 methanol masers towards 28 locations, 16 of which are new detections. The velocities of most of these masers are consistent with being located within the CMZ. A majority of the detected methanol masers are distributed towards positive Galactic longitudes, similar to 2/3 of the molecular gas mass distributed at positive Galactic longitudes. The 6.7 GHz methanol maser is an excellent indicator of high mass (>8 solar mass) star formation, with new detections indicating sites of massive star formation in the CMZ.

arXiv comment18 pages, 9 figures, 3 tables, MNRAS (in press)

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Cited by in corpus (13)

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• CMZoom: Survey Overview and First Data Release
• A Census of Early Phase High-Mass Star Formation in the Central Molecular Zone
• Detection of new methanol maser transitions associated with G358.93-0.03
• A Keplerian disk with a four-arm spiral birthing an episodically accreting high-mass protostar
• A Global View on Star Formation: The GLOSTAR Galactic Plane Survey V. 6.7 GHz Methanol Maser Catalogue
• A multi-transition methanol maser study of the accretion burst source G358.93-0.03-MM1
• The initial conditions for young massive cluster formation in the Galactic Centre: convergence of large-scale gas flows
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• High-Sensitivity Observations of Molecular Lines with the Arecibo Telescope
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• Discovery of non-metastable ammonia masers in Sagittarius B2
• 6.7 GHz CH3OH absorption towards the N3 Galactic Center point-source