LBA observations for project V576 semester 2020OCTS

The nearest AGB star R Dor is one of the best targets of VLTI and ALMA for the study of the physical, chemical, and dynamical properties of the AGB star. There are controversies on if there is strong wind acceleration or slower wind in its circumstellar environment (CSE), and if the measured rotation is from the rotating star of a rotating disk. Therefore, we propose multi-epoch phase-referencing LBA observations of 22 GHz H2O masers toward R Dor to measure their 3D kinematics. This project can provide (1) the transverse velocity to verify the rotation, and (2) the proper motions and possible acceleration in CSE, which also will show the maser kinematics dominated by radial expansion or collimated jets.