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Title: HST proper motions on the far side of the Galactic bar—data
ABSTRACT This is the third paper in a series that attempts to observe a clear signature of the Galactic bar/bulge using kinematic observations of the bulge stellar populations in low foreground extinction windows. We report on the detection of ∼100 000 new proper motions in four fields covering the far side of the Galactic bar/bulge, at negative longitudes. Our proper motions have been obtained using observations from the Advance Camera for Surveys (ACS), on board of the Hubble Space Telescope (HST), with a time-baseline of 8–9 years, which has produced accuracies better than 0.5 mas yr−1 for a significant fraction of the stellar populations with F814W < 23 mag. Interestingly, as shown in previous works, the Hess diagrams show a strikingly similar proper motion distribution to fields closer to the Galactic center and consistent with an old stellar population. The observed kinematics point to a significant bulge rotation, which seems to predominate even in fields as far as l ≃ −8°, and is also reflected in the changes of the velocity ellipsoid in the l, b plane as a function of distance.  more » « less
Award ID(s):
2009836
PAR ID:
10429323
Author(s) / Creator(s):
; ; ; ; ; ; ; ; ; ; ; ;
Publisher / Repository:
Oxford University Press
Date Published:
Journal Name:
Monthly Notices of the Royal Astronomical Society
Volume:
524
Issue:
1
ISSN:
0035-8711
Format(s):
Medium: X Size: p. 224-234
Size(s):
p. 224-234
Sponsoring Org:
National Science Foundation
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