The BAaDE SiO maser survey at 86GHz with ALMA

A 71% detection rate of 86GHz SiO masers is obtained from the infrared color-selected sample and increases to 80% when considering the likely oxygen-rich stars using Midcourse Space Experiment colors isolated in a region where [D]-[E]<=1.38.

Based on Galactic distributions, the presence of extended CS emission, and likely kinematic associations, the population of sources with [D]-[E]>1.38 probably consists of young stellar objects, or alternatively, of planetary nebulae. For the SiO detections, we examined whether individual SiO transitions provide comparable stellar line-of-sight velocities and found that any SiO transition is suitable for determining a stellar AGB line-of-sight velocity.