Stellar Kinematics of the Bulge from HST Proper Motion Measurements
نویسنده
چکیده
I report on an ongoing programme of proper motion measurements in the Galactic Bulge, using HST images. As a first application, the data are used to derive the vertical gravitational acceleration on the minor axis of the Galaxy. Implications of the measurement for the flattening of the Galactic potential are discussed.
منابع مشابه
HST / WFPC 2 proper motions in two bulge fields : kinematics and stellar population of the Galactic bulge
We report proper motion dispersions for stars in the direction of two fields of the Galactic bulge, using HST/WFPC2 images taken six years apart. Our two fields are Baade’s Window (l, b) = (1.13◦,−3.77◦) and Sgr I (l, b) = (1.25◦,−2.65◦). Our proper motion dispersions are in good agreement with prior groundand space-based proper motion studies in bulge fields, but in contrast to some prior stud...
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We report proper motion dispersions for stars in the direction of two fields of the Galactic bulge, using HST/WFPC2 images taken six years apart. Our two fields are Baade’s Window (l, b) = (1.13◦,−3.77◦) and Sgr I (l, b) = (1.25◦,−2.65◦). Our proper motion dispersions are in good agreement with prior groundand space-based proper motion studies in bulge fields, but in contrast to some prior stud...
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