Empirical Uncertainty Estimators for Astrometry from Digital Databases
Empirical Uncertainty Estimators for Astrometry from Digital Databases
复制标题
来自数字数据库的天体测量经验不确定性估计器
DOI：
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发表时间：
1999
期刊：
影响因子：
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通讯作者：
E. Deutsch
中科院分区：
文献类型：
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作者：
E. Deutsch
为了了解目前几个包含天体测量信息的主要数据库中任意物体的位置不确定性，将在国际天体参考架中具有精确位置的河外射电源样本与其光学对应物的可用位置进行比较。无线电和各种光学位置之间的差异被用来推导USNO-A2.0和USNO-A1.0星表，指南星星选择系统图像，第一和第二次数字化巡天的经验不确定性估计。此外，当USNO-A2.0目录被转移到不同的图像数据的不确定性的估计。在某些情况下，这些光学天体测量坐标系的不确定性可能是交叉识别不同波长源时的主要误差项。
In order to understand the positional uncertainties of arbitrary objects in several of the current major databases containing astrometric information, a sample of extragalactic radio sources with precise positions in the International Celestial Reference Frame is compared with the available positions of their optical counterparts. The discrepancies between the radio and various optical positions are used to derive empirical uncertainty estimators for the USNO-A2.0 and USNO-A1.0 catalogs, the Guide Star Selection System images, and the first and second Digitized Sky Surveys. In addition, an estimate of the uncertainty when the USNO-A2.0 catalog is transferred to different image data is provided. These optical astrometric frame uncertainties can in some cases be the dominant error term when cross-identifying sources at different wavelengths.