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Title: Astrometric Calibration of the Beijing–Arizona Sky Survey
Abstract We present the astrometric calibration of the Beijing–Arizona Sky Survey (BASS). The BASS astrometry was tied to the International Celestial Reference Frame via the Gaia Data Release 2 reference catalog. For effects that were stable throughout the BASS observations, including differential chromatic refraction and the low charge transfer efficiency of the CCD, we corrected for these effects at the raw image coordinates. Fourth-order polynomial intermediate longitudinal and latitudinal corrections were used to remove optical distortions. The comparison with the Gaia catalog shows that the systematic errors, depending on color or magnitude, are less than 2 milliarcseconds (mas). The position systematic error is estimated to be about −0.01 ± 0.7 mas in the region between 30° and 60° of decl. and up to −0.07 ± 0.9 mas in the region north of decl. 60°.  more » « less
Award ID(s):
1908284
PAR ID:
10492481
Author(s) / Creator(s):
; ; ; ; ; ; ; ; ; ; ; ; ; ; ;
Publisher / Repository:
The Astronomical Journal
Date Published:
Journal Name:
The Astronomical Journal
Volume:
165
Issue:
4
ISSN:
0004-6256
Page Range / eLocation ID:
172
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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