Back to Volume
Paper: VLBI Studies of Circumstellar Masers
Volume: 340, Future Directions in High Resolution Astronomy: The 10th Anniversary of the VLBA
Page: 373
Authors: Boboltz, D.A.
Abstract: Asymptotic giant branch (AGB) stars represent an important stage of stellar evolution. Astronomical masers are prevalent in the circumstellar envelopes of oxygen-rich AGB stars. Maser emission from the three most common masing molecules, OH, H2O and SiO, traces regions of the circumstellar envelope(CSE) on angular scales from tens of milliarcseconds to a few arcseconds. Masers provide a unique probe of structure, kinematics, and polarization properties in the environments of these stars. In this review I discuss previous VLBI investigations of the three common masing molecules toward AGB stars concentrating on more recent observations. I will also discuss future trends in astronomical maser observations including the move toward higher observing frequencies, the use of circumstellar masers for high-precision astrometry, and coordinated observations with Optical/IR long-baseline interferometers.
Back to Volume