标题： Aspera小卫星任务中对污染敏感的远紫外光谱仪的光学对准 显示英文标题

标题： Optical alignment of contamination-sensitive Far-Ultraviolet spectrographs for Aspera SmallSat mission

摘要： “阿斯佩拉”是美国宇航局（NASA）天体物理学先锋小型卫星任务，旨在研究附近星系晕中的温热相气体发出的弥散OVI辐射。 其有效载荷由两个相同的罗兰圆型长缝光谱仪组成，共享一个微通道板探测器。 每个光谱仪通道包括一个离轴抛物面主镜和优化用于1013至1057埃波段的环形衍射光栅。 尽管配置简单，由于紧凑的设计形式和远紫外线光学器件及探测器对污染的高度敏感性，阿斯佩拉的光学对准/集成过程具有挑战性。 本文讨论了使用最先进的光学计量工具实施一种新颖的多阶段方法以满足这些要求。 为了大致定位光学元件，我们使用蓝激光3D扫描仪，而精细对准则通过Zygo干涉仪和定制计算机生成全息图完成。 探测器焦点需要使用真空紫外平行光管进行迭代的真空内对准。 对准工作是在亚利桑那大学的一个受控洁净室设施中进行的。 显示英文摘要

摘要： Aspera is a NASA Astrophysics Pioneers SmallSat mission designed to study diffuse OVI emission from the warm-hot phase gas in the halos of nearby galaxies. Its payload consists of two identical Rowland Circle-type long-slit spectrographs, sharing a single MicroChannel plate detector. Each spectrograph channel consists of an off-axis parabola primary mirror and a toroidal diffraction grating optimized for the 1013-1057 Angstroms bandpass. Despite the simple configuration, the optical alignment/integration process for Aspera is challenging due to tight optical alignment tolerances, driven by the compact form factor, and the contamination sensitivity of the Far-Ultraviolet optics and detectors. In this paper, we discuss implementing a novel multi-phase approach to meet these requirements using state-of-the-art optical metrology tools. For coarsely positioning the optics we use a blue-laser 3D scanner while the fine alignment is done with a Zygo interferometer and a custom computer-generated hologram. The detector focus requires iterative in-vacuum alignment using a Vacuum UV collimator. The alignment is done in a controlled cleanroom facility at the University of Arizona.