Collaborative Research: Advanced Wavefront Sensing and Control for Exoplanet Imaging at W. M. Keck Observatory

合作研究：W. M. Keck 天文台的系外行星成像先进波前传感和控制

• 批准号: 2008822
• 负责人: Rebecca Jensen-Clem
• 金额: $ 36.23万
• 依托单位: University of California-Santa Cruz
• 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 2025-08-31
• 项目状态: 未结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2008822&HistoricalAwards=false
• 关键词: Collaborative; Research; Advanced; Wavefront; Sensing

Taking pictures of planets around other stars is difficult, because stars are much brighter than planets. However, images of other planets can also tell us what the planet is made of, what its weather might be like, how it formed, and whether it might be home to life. So far, astronomers have only managed to image a handful of planets outside the Solar System, and these planets are unusually hot, bright, and far from their suns. To take pictures of Earth-like planets (which are faint and very close to their suns) astronomers must overcome issues like the turbulence in Earth’s atmosphere and imperfections in the telescope optics. This project will tackle both these issues. A new predictive control method will be investigated that both anticipates the upcoming turbulence, and develops methods to measure and correct the internal optical errors of telescopes. The project’s investigators are involved in teaching and mentoring at the new “AstroTech” summer school. Students from underrepresented and underserved populations in Hawaii will be directly involved in this research through Akamai Workforce Initiative internships and through the University of Hawaii at Hilo. These new approaches will be demonstrated at the Keck Observatory.The last three decades have been marked by the discovery of over 4000 exoplanets orbiting nearby stars. Direct imaging is the preferred method for obtaining high signal-to-noise, high-resolution spectra of diverse exoplanet atmospheres. The performance of modern high contrast imaging systems is limited by the ability to sense and correct the lowest order wavefront aberrations that give rise to contaminating starlight close to the telescope’s diffraction limit. This project will implement two technologies at Keck Observatory to improve spatial resolution. Firstly, predictive wavefront control will minimize the effect of time lag between wavefront sensing and control that results in quickly- evolving speckles at low spatial frequencies. Secondly, focal plane wavefront control that minimizes instrument aberrations that are poorly sensed by the existing adaptive optics systems that give rise to wavefront “speckle” errors.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.

在其他恒星周围拍照是困难的，因为恒星比行星亮得多。但是，其他行星的图像还可以告诉我们地球是什么，天气可能是什么，形成方式以及它是否是生活的家园。到目前为止，天文学家仅设法在太阳系以外的少数行星上进行想象，这些行星异常热，明亮，远离太阳。为了拍摄类似地球的行星（微弱且非常靠近太阳）的照片，天文学家必须克服诸如地球大气中的湍流和望远镜光学的缺陷之类的问题。该项目将解决这两个问题。将研究一种新的预测控制方法，既可以预测即将到来的湍流，又开发了测量和纠正望远镜内部光学误差的方法。该项目的调查人员参与了新的“ Astrotech”暑期学校的教学和心理化。来自夏威夷人口不足和服务不足人群的学生将通过Akamai Workerforce倡议实习和夏威夷大学Hilo直接参与这项研究。这些新方法将在凯克天文台进行证明。最近三十年来发现了4000多个绕着附近恒星绕的系外行星。直接成像是获得分歧外球星大气的高信噪比高分辨率光谱的首选方法。现代高对比度成像系统的性能受到感知和纠正最低订单波前畸变的能力的限制，从而导致远离望远镜的衍射极限的污染星光。该项目将在凯克天文台实施两种技术，以改善空间分辨率。首先，预测波前控制将最大程度地减少波前灵敏度和控制之间的时间滞后的效果，从而在低空间频率下迅速发展斑点。其次，现有的自适应光学系统对仪器的畸变最小化，而现有的自适应光学系统会导致波浪前“斑点”错误所感知的仪器畸变。该奖项反映了NSF的法定任务，并通过使用基金会的知识分子和更广泛的影响来审查审查标准来通过评估来诚实地诚实地支持。