Probing the Galactic AGB population through SiO maser emission

With an unprecedentedly large sample of uniformly selected asymptotic giant branch (AGB) stars, we present results focused on understanding the intermediate-age stellar populations in the Milky Way. Via radio and mm observations, the Bulge Asymmetries and Dynamical Evolution (BAaDE) survey has detected SiO maser emission in about 10,000 AGB stars, effectively probing the AGB stellar kinematics via their velocities. Here we show how combinations of MSX, 2MASS, Gaia, and BAaDE data can be used to characterize Galactic AGB stars. Results include comments on the completeness, scale, and efficiency of the survey; IR constraints on colors of SiO-hosts; observations of rare isotopologue transitions; and presentation of the largest collection of SiO line ratios and their implications for maser pumping models.