Physics & Astronomy ETDs

Publication Date

Summer 7-8-2019


The Bulge Asymmetries and Dynamical Evolution (BAaDE) project aims to explore the complex structure of the inner Galaxy and Galactic Bulge, by using the 43 GHz receivers at the Karl G. Jansky Very Large Array (VLA) and the 86 GHz receivers at the Atacama Large Millimeter/submillimeter Array (ALMA) to observe SiO maser lines in red giant stars. The SiO maser transitions occur at radio frequencies, where extinction is negligible, thus allowing a dense sampling of line-of-sight velocities in the most crowded regions of the Milky Way.

The overall goal of this thesis is to characterize the SiO masers in the BAaDE survey, which is the largest circumstellar SiO survey to date. Circumstellar SiO masers can provide information about the conditions in the circumstellar shell including density, temperature, radiation environment, and perhaps also the mass loss rates. The pumping mechanism for SiO maser emission around AGB stars is not fully understood and may require both collisional and radiative pumping. Thus a large statistical analysis of the SiO maser will aid in the creation and testing of future SiO pumping models.

Degree Name


Level of Degree


Department Name

Physics & Astronomy

First Committee Member (Chair)

Ylva Pihlström

Second Committee Member

Richard Rand

Third Committee Member

Gregory Taylor

Fourth Committee Member

Loránt Sjouwerman




masers, AGB stars, SiO

Document Type