Studying high-mass star formation & galactic structure through the methanol multibeam survey

• Main Author: Green, James Andrew
• Published: University of Manchester 2008
• Subjects: 523.8
• Online Access: http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.491493

This thesis presents the techniques and procedures that enable a new Galactic plane survey for 6668-MHz methanol masers, exclusive signposts of high-mass star formation. The statistics and properties of the largest ever sample of 6668MHz methanol masers arc detailed, including completeness and total population estimates. Through the application of rotation curves the distances are found, which then facilitates establishing the Galactic distribution of these masers, and thus of high-mass star formation regions. The relationship between these and the Spiral arms is examined. The most accurate luminosity distribution of 6668MHz methanol masers in the Galaxy and the Large Magellanic Cloud are given, together with new detections of 6668-MHz methanol and 6035-MHz hydroxyl masers in the Large Magellanic Cloud. A high spatial resolution study of an individual massive star formation region, aNI, is also presented, which not only details the precise structure and relation of methanol and excited-state hydroxyl to other species of masers for the first time, but also presents the first tentative detection of Zeeman splitting in a 6668-MHz methanol maser.