论文标题
PAN-Starrs1天文统计的改进：II。差异色折射的校正
Improvements to Pan-STARRS1 Astrometry: II. Corrections for Differential Chromatic Refraction
论文作者
论文摘要
在上一篇论文中，我们应用了GAIA DR2目录，以提高Pan-Starrs1数据释放2（PS1 DR2）中约17亿个物体的天体精度。我们在此报告通过利用Gaia EDR3和校正差分色折射（DCR）在偏斜中的影响进行进一步改进。我们通过迭代减去颜色依赖性PS1/GAIA EDR3偏斜残差来扩展纸条1中的校正算法。我们确定了约4.4亿个参考物体的星体改进，与Gaia EDR3相交，并交叉匹配。对于这组对象，Gaia EDR3比Gaia DR2的PS1天文测量值提高了约3％，而DCR校正可提供额外的〜5％改善。远离天顶的物体大大增加了DCR校正。 DCR校正导致距离天顶50°的蓝色物体（0 <g-i <1）的天体改善约为30％。对于在0 <g-i <4.5范围内具有PS1颜色的对象，这些效果的系统天文误差的幅度大大降低到1个MAS，这使得这是Gaia恒星几乎没有的田野中有用的天文参考目录。改进的星体数据将通过Mikulski档案供太空望远镜PS1目录界面获得。
In a previous paper, we applied the Gaia DR2 catalog to improve the astrometric accuracy of about 1.7 billion objects in Pan-STARRS1 Data Release 2 (PS1 DR2). We report here on further improvements made by utilizing Gaia EDR3 and correcting for the effects of differential chromatic refraction (DCR) in declination. We extend the correction algorithm in Paper 1 by iteratively subtracting color- and declination-dependent PS1/Gaia EDR3 declination residuals. We determine the astrometric improvement for ~440 million reference objects that are point-like and cross-match to Gaia EDR3. For this set of objects, Gaia EDR3 provides a ~3% improvement in PS1 astrometry over Gaia DR2, and DCR corrections provide an additional ~5% improvement. DCR corrections increase substantially for objects observed away from the zenith. DCR corrections lead to an astrometric improvement of ~30% for blue objects (0<g-i<1) that are 50° away from the zenith. The amplitude of systematic astrometric errors from these effects is substantially reduced to less than 1 mas for objects with PS1 colors in the range 0 < g-i < 4.5, which makes this a useful astrometric reference catalog in fields where there are few Gaia stars. The improved astrometric data will be available through the Mikulski Archive for Space Telescopes PS1 catalog interfaces.
