The Habitable-Zone Exoplanet Observatory Mission (HabEx) is one of four large missions under review for the 2020 astrophysics decadal survey. Its goal is to directly image and spectroscopically characterize planetary systems in the habitable zone around nearby Sun-like stars. In addition, HabEx will perform a broad range of general astrophysics science enabled by a 115- to 1700-nm spectral range and 3 × 3 arcminute field of view. Critical to achieving its science goals, HabEx requires a large, ultrastable UV/optical/near-IR telescope. Using science-driven systems engineering, HabEx specified its baseline telescope to be a 4-m off-axis, unobscured three-mirror anastigmatic architecture with diffraction-limited performance at 400 nm, and wavefront stability on the order of a few tens of picometers. We summarize the systems-engineering approach to the baseline telescope assembly’s optomechanical design, including a discussion of how science requirements drive the telescope’s specifications. We also present structural thermal optical performance analysis showing that the baseline telescope structure meets its specified tolerances. We report new and updated analysis that is not in the HabEx final report.

中文翻译：

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居住区系外行星天文台基线4米望远镜：系统工程设计过程和预测的结构热光学性能

宜居地带系外行星天文台任务（HabEx）是2020年天体物理学十年调查中正在审查的四个大型任务之一。它的目标是在附近类似太阳的恒星周围的宜居带中，对行星系统进行直接成像和光谱表征。此外，HabEx将在115至1700 nm的光谱范围和3×3 arcminute的视场范围内，执行广泛的一般天体物理学科学。对于实现其科学目标至关重要，HabEx需要大型，超稳定的UV /光学/近红外望远镜。HabEx使用科学驱动的系统工程，将其基线望远镜指定为4 m偏轴，无遮挡的三面镜吻合结构，在400 nm处具有衍射极限性能，波前稳定性约为几十皮米。我们总结了基线望远镜组件的光机械设计的系统工程方法，包括对科学要求如何驱动望远镜规格的讨论。我们还提供了结构热光学性能分析，表明基线望远镜结构满足其指定的公差。我们报告了HabEx最终报告中未包含的新的和更新的分析。