Prototyping a New Telescope Design for Unprecedented Survey Speed in the Infrared

原型设计新型望远镜，实现前所未有的红外观测速度

• 批准号: 2010041
• 负责人: Roger Smith
• 金额: $ 78.86万
• 依托单位: California Institute of Technology
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2020
• 资助国家: 美国
• 起止时间: 2020-09-01 至 2024-02-29
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2010041&HistoricalAwards=false
• 关键词: Prototyping; New; Telescope; Design; Unprecedented

Our Universe is full of fireworks. Events like colliding neutron stars are not only spectacular but can explain how heavy elements like gold were created. However, like fireworks hidden by their own smoke, scientist can only “hear” their gravitational waves. Astronomers in addition need to “see” the flash of light to know exactly where these explosions are, their colors and their secrets. Fortunately, infrared light penetrates the obscuring material. To catch these events before they fade, we need an infrared camera that records larger sections of the sky in one image than what is available at present. In the system being developed under this award, the entire telescope will be cryogenically cooled so that it doesn't emit a glow in infrared light. This project will build a quarter-scale prototype of a 1m diameter telescope that is planned for use in the Antarctic where the infrared sky is much darker. Such a system will be an infrared complement to the Vera Rubin Observatory. The team will integrate education and research by supporting undergraduate engineering and astronomy students working directly on this technology development. Graduate students will conduct demonstration science under the supervision of the project scientist. This project will develop a new infrared telescope that will utilize a pair of fused silica meniscus lenses placed symmetrically about the pupil to correct for the aberrations introduced by the spherical primary. This geometry achieves low chromatic aberration to deliver diffraction limited images at focal ratios as fast as f/1.2, without requiring dissimilar glasses. The convex fused silica second element is strong enough to support atmospheric pressure, enabling a fully cryogenic optical path through its use as the dewar window. The only warm surfaces seen by the detector are the transparent first element and a thin annulus at the pupil stop, which is configured as a low emissivity narcissus mirror. Key goals of the prototype are to confirm the predicted low thermal background, high throughput and good image quality at f/2 using a 250 mm aperture. A 2.5 μm cutoff Teledyne H2RG detector will cover a 17.8 deg2 field of view with 7.4 arcsec/pixel sampling. Three undergraduate students will be involved in demonstrating key technologies. These include measures to keep the entrance window above dew point, high precision focus and tilt control via thermal expansion of the primary mirror support bipods, and a novel detector readout mode for higher observing efficiency and enhanced dynamic range. This project advances the goals of the Windows on the Universe Big Idea.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.

我们的宇宙充满了烟火。像中子星碰撞这样的事件不仅壮观，而且可以解释像金这样的重元素是如何产生的。然而，就像烟花被自己的烟雾所掩盖一样，科学家们只能“听到”它们的引力波。天文学家还需要“看到”闪光，才能确切地知道这些爆炸的位置，它们的颜色和秘密。幸运的是，红外线可以穿透这些遮蔽材料。为了在这些事件消失之前捕捉到它们，我们需要一台红外相机，它可以在一张图像中记录比目前可用的更大的天空部分。在该奖项下开发的系统中，整个望远镜将被低温冷却，以便它不会发出红外光。该项目将建造一个1米直径望远镜的四分之一比例原型，计划在红外天空暗得多的南极使用。这样一个系统将是维拉鲁宾天文台的红外补充。该团队将通过支持直接从事这项技术开发的本科工程和天文学学生来整合教育和研究。研究生将在项目科学家的监督下进行示范科学。该项目将开发一种新的红外望远镜，该望远镜将利用一对关于瞳孔对称放置的熔融石英弯月形透镜来校正由球面主镜引入的像差。这种几何结构实现了低色差，以f/1.2的焦比提供衍射限制图像，而不需要不同的玻璃。凸形熔融石英第二元件的强度足以支持大气压，从而通过其作为杜瓦瓶窗口的使用实现完全低温的光路。探测器看到的唯一温暖的表面是透明的第一元件和光瞳光阑处的薄环，其被配置为低发射率水仙镜。原型的主要目标是确认预测的低热背景，高吞吐量和良好的图像质量在f/2使用250 mm光圈。2.5 μm截止Teledyne H2 RG探测器将覆盖17.8 deg 2视场，采样率为7.4 arcsec/像素。三名本科生将参与演示关键技术。这些措施包括将入射窗保持在露点以上，通过主镜支撑双脚架的热膨胀进行高精度聚焦和倾斜控制，以及用于更高观察效率和增强动态范围的新型探测器读出模式。该项目推进了"宇宙大创意视窗“的目标。该奖项反映了NSF的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。