OTA图像天体测量结果的WCS-SIP参数表达  

The Representation of OTA Images' Astrometric Results with WCS-SIP Coefficients

作　　者：平一鼎[1,2] 张晨[1,2,3] 鲁春林[1,2] 

机构地区：[1]中国科学院紫金山天文台,南京210008 [2]中国科学院空间目标与碎片观测重点实验室,南京210008 [3]中国科学技术大学天文与空间科学学院,合肥230026

出　　处：《天文学报》2017年第3期79-88,共10页Acta Astronomica Sinica

基　　金：国家自然科学基金项目(11373071;11673070;11603082)资助

摘　　要：为了在OTA(Optical Telescopes Array)巡天项目中发现特定源的位置或者光度的变化,需要将观测图像中的目标与星表或不同历元的历史数据进行交叉比对,这就需要知道图像中目标的天球坐标.一种基于矩阵计算的方法被用于将OTA已有的底片常数变换至WCS(World Coordinate System)和SIP(Simple Imaging Polynomial)参数,并将这样的映射关系记录到OTA的FITS(Flexible Image Transport System)图像中以便于利用.在此过程中改进了OTA的天体测量方法.在此基础上对OTA天体测量中的一些问题进行了讨论.Cross-matching the sources extracted from observed images with refer- ence catalogs or earlier records is a necessary procedure for seeking the variation of sources in terms of position or brightness for the Optical Telescopes Array （0TA） sur- vey. Knowing the celestial positions of these objects on images is prerequisite therefore. A method based on matrix manipulation is applied to transform the existing calculated plate constants of OTA images into World Coordinate System （WCS） coefficients and Simple Imaging Polynomial （SIP） coefficients, which map image positions into celestial positions so as to facilitate the mining of the FITS （Flexible Image Transport System） images of OTA. An improvement of OTA＇s astrometry coming with this method, as well as the discussion about some problems of OTA＇s astrometry are also presented.

关 键 词：天体测量学 巡天 技术 图像处理 

分 类 号：P129[天文地球—天体测量]