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Title: Kinematics in the Galactic Center with SiO masers
Abstract Stellar SiO masers are found in the atmospheres of asymptotic giant branch (AGB) stars with several maser transitions observed around 43 and 86 GHz. At least 28 SiO maser stars have been detected within ∼2 pc projected distance from Sgr A* by the Very Large Array (VLA) and Atacama Millimeter/submillimeter Array (ALMA). A subset of these masers have been studied for several decades and form the basis of the radio reference frame that anchors the reference frame for infrared stars in the Galactic Center (GC). We present new observations of the GC masers from VLA and ALMA. These new data combined with extant maser astrometry provide 3D positions, velocities, and acceleration limits. The proper motions and Doppler velocities are measured with unprecedented precision for these masers. We further demonstrate how these measurements may be used to trace the stellar and dark matter mass distributions within a few pc of Sgr A*.  more » « less
Award ID(s):
1908122
PAR ID:
10536851
Author(s) / Creator(s):
;
Editor(s):
Hirota, T; Imai, H; Menten, K; Pihlström, Y
Publisher / Repository:
Cambridge University Press
Date Published:
Journal Name:
Proceedings of the International Astronomical Union
Volume:
18
Issue:
S380
ISSN:
1743-9213
Page Range / eLocation ID:
101 to 105
Subject(s) / Keyword(s):
Silicon monoxide masers stellar masers Galactic Center stellar kinematics
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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