Gaia星表的合成光度仪器星等估计方法  

Synthetic photometry instrument magnitude estimation method of Gaia catalogue

作　　者：安悦晗 武延鹏[1] 孟小迪 AN Yuehan;WU Yanpeng;MENG Xiaodi(Beijing Institute of Control Engineering,Beijing 100190,China)

机构地区：[1]北京控制工程研究所,北京100190

出　　处：《光学精密工程》2023年第8期1107-1114,共8页Optics and Precision Engineering

基　　金：国家自然科学基金资助项目(No.51905034)。

摘　　要：为满足星敏感器灵敏度的测量、导航星表的建立、空间目标的捕获等任务需求,需要精确的仪器星等作为数据支持。本文对仪器星等计算的方法及测光系统方面展开研究。首先,结合仪器星等计算原理介绍了以GaiaDR2星表为数据源的基于合成光度法的Gaia仪器星等计算方法,即基于G,G_(BP),G_(RP)星等系统的合成光度计算及色指数模型。其次,利用星表数据进行实例计算,并对仪器星等计算精度及色指数模型进行比较分析。最后,对星敏感器在轨图像进行孔径测光,得到实际仪器星等结果与计算结果进行对比验证,并结合实际星等比较本文提出的方法与UBV色指数拟合法的结果。结果表明,Gaia星表的合成光度仪器星等估计方法与UBV色指数拟合法计算仪器星等与实际仪器星等差(McMr)标准差分别为0.066和0.075。本文提出的方法达到了较高的仪器星等计算精度且能够满足实际应用需求。To meet the requirements of measuring the sensitivity of star trackers,establishing guide star catalogs,and capturing space targets,accurate instrument magnitudes are required as data support.In this study,the method of instrument magnitude calculation and photometric system are investigated.First,combined with the principle of instrument magnitude calculation,synthetic photometric method and color index fitting method are introduced.Then,the instrument magnitude calculation method of Gaia catalog based on synthetic photometry using GaiaDR2 catalog,that is,synthetic photometric calculation and color index model based on the G,G_(BP),G_(RP) star system,is introduced as the data source.Subsequently,color in⁃dex model accuracy of other instrument magnitude calculation methods is calculated.Finally,aperture photometry is performed on the in-flight image of the star tracker,and the actual instrument magnitude re⁃sults are compared and verified with the calculated results.The calculation results of the GaiaDR2 catalog and Hipparcos catalog are compared with the actual magnitude.The results show that the standard devia⁃tions of the color index fittings using the calculated value and true value of GaiaDR2 are 0.0035 and 0.0376,respectively.The standard deviation of the calculated instrument magnitude difference(Mc-Mr)is 0.1060,and the spectral coverage is relatively larger.Thus,it achieves high precision and can meet the needs of practical applications.

关 键 词：仪器星等 Gaia星表 色指数 合成光度学 

分 类 号：V448.22[航空宇航科学与技术—飞行器设计]