THE PPMXL CATALOG OF POSITIONS AND PROPER MOTIONS ON THE ICRS. COMBINING USNO-B1.0 AND THE TWO MICRON ALL SKY SURVEY (2MASS)
THE PPMXL CATALOG OF POSITIONS AND PROPER MOTIONS ON THE ICRS. COMBINING USNO-B1.0 AND THE TWO MICRON ALL SKY SURVEY (2MASS)
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DOI：
10.1088/0004-6256/139/6/2440
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发表时间：
2010-03
期刊：
影响因子：
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通讯作者：
Siegfried Roeser;Markus Demleitner;E. Schilbach
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文献类型：
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作者：
Siegfried Roeser;Markus Demleitner;E. Schilbach
USNO-B1.0和2微米全天巡天（2 MASS）是应用最广泛的全天巡天。然而，2 MASS根本没有自行，USNO-B1.0公布的只是相对的，而不是绝对的（即，在国际天体参考系（ICRS）上，自行。利用USNO-B1.0和2 MASS天体测量相结合的方法，在ICRS系统上进行了一次新的平均位置和自行的测定。这个星表被称为PPMXL（VO访问该星表是可能的通过http：//vo.uni-hd.de/ppmxl），它的目标是完成从最亮的恒星到大约V-20整个天空。PPMXL包含约9亿个天体，其中约4.1亿个采用2 MASS测光，是目前ICRS自行最大的集合。作为ICRS的代表，我们选择了PPMX。最近发布的UCAC 3不能使用，因为我们发现它的自行系统在-20 °赤纬以北存在与板相关的扭曲。UCAC 3是δ θ −20°的中间系统。由此产生的自行的典型个体平均误差范围从4 mas yr-1到10 mas yr-1以上，取决于观测历史。2000.0历元位置的平均误差为80-120 mas，若采用2 MASS天体测量，则为150-300 mas。我们还给出了校正表，以转换USNO-B1.0观测，例如，ICRS系统的小行星
USNO-B1.0 and the Two Micron All Sky Survey (2MASS) are the most widely used all-sky surveys. However, 2MASS has no proper motions at all, and USNO-B1.0 published only relative, not absolute (i.e., on the International Celestial Reference Frame (ICRS), proper motions. We performed a new determination of mean positions and proper motions on the ICRS system by combining USNO-B1.0 and 2MASS astrometry. This catalog is called PPMXL (VO access to the catalog is possible via http://vo.uni-hd.de/ppmxl), and it aims to be completed from the brightest stars down to about V ≈ 20 all sky. PPMXL contains about 900 million objects, some 410 million with 2MASS photometry, and is the largest collection of ICRS proper motions at present. As representative for the ICRS, we chose PPMX. The recently released UCAC3 could not be used because we found plate-dependent distortions in its proper motion system north of −20° declination. UCAC3 served as an intermediate system for δ ⩽ −20°. The resulting typical individual mean errors of the proper motions range from 4 mas yr−1 to more than 10 mas yr−1 depending on observational history. The mean errors of positions at epoch 2000.0 are 80–120 mas, if 2MASS astrometry could be used, 150–300 mas else. We also give correction tables to convert USNO-B1.0 observations of, e.g., minor planets to the ICRS system.