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arXiv · 1202.5892

3-Dimensional Kinematics in low foreground extinction windows of the Galactic Bulge: Radial Velocities for 6 bulge fields

M. Soto·K. Kuijken·R. M. Rich
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Abstract

The detailed structure of the Galactic bulge still remain uncertain. The strong difficulties of obtaining observations of stars in the Galactic bulge have hindered the acquisition of a kinematic representation for the inner kpc of the Milky Way. The observation of the 3-d kinematics in several low foreground extinction windows can solve this problem. We have developed a new technique, which combines precise stellar HST positions and proper motions with integral field spectroscopy, in order to obtain reliable 3-d stellar kinematics in crowded fields of the Galactic center. In addition, we present results using the new techniques for six fields in our project. A significant vertex deviation has been found in some of the fields in agreement with previous determinations. This result confirms the presence of a stellar bar in the Galactic bulge.

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M. Soto, K. Kuijken, R. M. Rich. 2012-02-27. 3-Dimensional Kinematics in low foreground extinction windows of the Galactic Bulge: Radial Velocities for 6 bulge fields. https://doi.org/10.1051/0004-6361/201116522

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