Design of the VLT-CUBES image slicers: Field re-formatters to provide two spectral resolutions
Design of the VLT-CUBES image slicers: Field re-formatters to provide two spectral resolutions
复制标题
VLT-CUBES 图像切片器的设计：提供两种光谱分辨率的场重新格式化器
DOI：
10.1007/s10686-022-09866-5
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发表时间：
2022
影响因子：
3
通讯作者：
Calcines A
中科院分区：
文献类型：
--
作者：
Calcines A
CUBES是为甚大望远镜的卡塞格伦焦点设计的高效光谱仪，预计将于2028年投入使用。它被设计用于观察光谱范围从300到405 nm的点源或紧凑源。CUBES将提供两种光谱分辨率：高分辨率（HR）为R20，000，低分辨率（LR）为R5，000。这是通过为每个分辨率模式使用图像切片器来实现的。图像切片器将1.5弧秒乘10弧秒（HR）或6弧秒乘10弧秒（LR）的天空上的矩形视场重新格式化为六个并排的狭缝，形成光谱仪狭缝。HR和LR的狭缝尺寸分别为0.19mm88mm和0.77mm88mm。在天空和物理宽度的切片镜是0.25 arcsec/0.5毫米（HR）和1 arcsec/2毫米（LR）。图像限幅器减小了光谱仪入口狭缝集光率，并且因此减小了光谱仪光学器件的尺寸，而没有相关联的狭缝损失。每个建议的图像切片器由两个阵列的六个球面镜（切片器反射镜和相机反射镜阵列），它提供了一个直的入口狭缝的光谱仪几乎衍射有限的光学质量。本文介绍了在A阶段概念设计结束时的图像切片器的描述，包括它们的光学设计和预期性能。
CUBES is a high efficiency spectrograph designed for a Cassegrain focus of the Very Large Telescope and is expected to be in operation in 2028. It is designed to observe point or compact sources in a spectral range from 300 to 405nm. CUBES will provide two spectral resolving powers: R20,000 for high resolution (HR) and R5,000 for low resolution (LR). This is achieved by using an image slicer for each resolution mode. The image slicers re-format a rectangular on-sky field of view of either 1.5arcsec by 10arcsec (HR) or 6arcsec by 10arcsec (LR) into six side-by-side slitlets which form the spectrograph slit. The slit dimensions are 0.19mm88mm for HR and 0.77mm88mm for LR. The on-sky and physical widths of the slicer mirrors are 0.25arcsec/0.5mm (HR) and 1arcsec/2mm (LR). The image slicers reduce the spectrograph entrance slit etendue and hence the size of the spectrograph optics without associated slit losses. Each of the proposed image slicers consists of two arrays of six spherical mirrors (slicer mirror and camera mirror arrays) which provide a straight entrance slit to the spectrograph with almost diffraction-limited optical quality. This paper presents the description of the image slicers at the end of the Phase A conceptual design, including their optical design and expected performance.