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NRAO/Socorro Colloquium Series

Nikta Amiri

University of Colorado

Maser Emission in the Galaxy and M31: Proper Motion, Maser Host Properties, and Magnetic Fields

Astrophysical maser emission is associated with early and late stages of a star's life. Water masers have been detected in five star forming regions in the Andromeda Galaxy (M31). The masers provide the high brightness temperature point sources needed for proper motion studies of M31, enabling measurement of its full three-dimensional velocity vector and its geometric distance via proper rotation. The results of our multi-wavelength study of water maser emitting regions show that there is a strong correlation between the Halpha flux and 24 micron emission for the masers, and that there is a region in parameter space based on 24 micron emission and Halpha flux that water masers form. Furthermore, bright maser emission has been detected in the outflows from evolved stars in the Galaxy. High angular resolution observations of the masers provide a unique tool to study the morphology of the outflows from evolved stars. In particular, polarimetric observations of the masers provide the most direct method on magnetic field strength and morphology at various distances from evolved stars. Our polarimetric observations indicate significant magnetic field strengths, which imply that magnetic fields can have an important role in collimating the jets and shaping the circumstellar environment of dying stars.


February 7, 2014
11:00 am

Array Operations Center Auditorium

All NRAO employees are invited to attend via video, available in Charlottesville 245, Green Bank Auditorium,  Tucson N525, and NTC 400.

Local Host: Mark Claussen

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