A New Distortion Solution for NIRC2 on the Keck II Telescope
A New Distortion Solution for NIRC2 on the Keck II Telescope
复制标题
Keck II 望远镜上 NIRC2 的新畸变解决方案
DOI：
10.1088/1538-3873/128/967/095004
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发表时间：
2016
影响因子：
3.5
通讯作者：
J. Anderson
中科院分区：
文献类型：
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作者：
M. Service;J. Lu;R. Campbell;B. Sitarski;A. Ghez;J. Anderson
提出了一种新的近红外相机（NIRC 2）窄场模式几何畸变模型。M.凯克二号望远镜。自适应光学系统和NIRC2相机于2015年4月13日重新校准。观测拥挤的球状星团，M53，之前和之后的重新排列，以表征几何场失真。M53恒星的扭曲的NIRC2位置与哈勃太空望远镜观测到的该星团的精确天体测量进行了比较。在重新排列之前构建的变形图与使用2007年至2009年的数据得出的先前解决方案一致，表明变形已稳定至1.05 mas。在4.5 mas（75%）rms的重新对准后，失真图发生了显著变化，重新对准后观测的新失真模型的总精度为1.1 mas。
We present a new geometric distortion model for the narrow-field mode of the near-infrared camera (NIRC2) fed by the adaptive optics system on the W. M. Keck II telescope. The adaptive optics system and NIRC2 camera were realigned on 2015 April 13. Observations of the crowded globular cluster, M53, were obtained before and after the realignment to characterize the geometric field distortion. The distorted NIRC2 positions of M53 stars were compared with precise astrometry of this cluster from Hubble Space Telescope observations. The resulting distortion map constructed just before the realignment is consistent with the previous solution derived using data from 2007 to 2009, indicating that the distortion has been stable to ∼0.5 mas. The distortion map changed significantly after a realignment of 4.5 mas (75%) rms, and the new distortion model for post-realignment observations have a total accuracy of ∼1.1 mas.