Collaborative Research: High Contrast Imaging at the Photon Noise Limit: On-Sky Validation of Speckle Reconstruction from WFS Telemetry

合作研究：光子噪声极限下的高对比度成像：WFS 遥测斑点重建的空中验证

• 批准号: 2308351
• 负责人: Jared Males
• 金额: $ 52.09万
• 依托单位: University of Arizona
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2023
• 资助国家: 美国
• 起止时间: 2023-09-01 至 2025-08-31
• 项目状态: 未结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2308351&HistoricalAwards=false
• 关键词: Collaborative; Research; Contrast; Imaging; Photon

Imaging extrasolar planets is challenging. Planets are typically one hundred thousand to ten billion times fainter than their host stars. Taking pictures of such planets requires nearly perfect control of light. Starlight is blocked using optical devices called "coronagraphs". Ground-based telescopes must deal with the additional problem of turbulence in the Earth's atmosphere. Turbulence causes the stars to twinkle, and telescopes remove this twinkle using a technique called "Adaptive Optics". Finally, image processing is performed to find the exoplanet signal in the noise. Current instruments do not image the faintest possible planets because they are limited by “speckles”, which are created by imperfections in all of the above steps. However not all the available information is currently used when analyzing such images. Nearly all image processing methods use only the science images themselves. This creates many biases and artifacts. This is especially true close to the star, where most planets can be found. The goal of this project is to find more planets by using all the combined information. Software will be written for two existing instruments, which will be used by astronomers to analyze their images. This software will be written to be easy to use and made freely available to astronomers. Students will be involved at both participating institutions.Direct imaging characterization of exoplanets has so far been limited to young, hot, and massive planets orbiting relatively far from their stars. Such planets are observable due to their intrinsic self-luminosity generated as they continue to cool after formation. Many more planets are observable if the inner working angle can be improved. Moreover, improving the sensitivity limit of high-contrast imaging will enable the characterization of fainter, lower-mass planets. The key to enabling more sensitive post-processing is to use the data simultaneously recorded by the suite of wavefront sensors (WFSs) in a modern high-contrast imaging system. These include the main high-order WFS as well as coronagraph low-order and focal plane WFS. The investigators, with the assistance of a post-doctoral researcher, will implement algorithms based on existing proofs of concept, test and validate these algorithms with lab and on-sky data, and deploy the software systems on the MagAO-X and SCExAO instruments. These two extreme-AO coronagraphic instruments share a common software framework and there is collaboration between the instrument teams. This system will be deployed so that users can use it to reduce their data to achieve the highest possible sensitivity at small separations. Making a telemetry-based post-processing system available on current generation instruments will dramatically improve their sensitivity.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.

为太阳系外行星成像是一项挑战。行星通常比它们的宿主恒星暗淡10万到100亿倍。拍摄这样的行星需要近乎完美的光线控制。星光被称为“日冕仪”的光学设备阻挡。地面望远镜必须处理地球大气湍流的附加问题。湍流导致恒星闪烁，望远镜使用一种叫做“自适应光学”的技术来消除这种闪烁。最后进行图像处理，在噪声中寻找系外行星信号。目前的仪器无法成像最微弱的行星，因为它们受到“斑点”的限制，这些斑点是由上述所有步骤中的缺陷造成的。然而，在分析这些图像时，目前并没有使用所有可用的信息。几乎所有的图像处理方法都只使用科学图像本身。这就产生了许多偏见和人为因素。在靠近恒星的地方尤其如此，因为大多数行星都可以在那里找到。这个项目的目标是利用所有的综合信息来发现更多的行星。将为现有的两台仪器编写软件，供天文学家用来分析他们的图像。该软件将被编写为易于使用，并免费提供给天文学家。学生将在两个参与机构参与。到目前为止，系外行星的直接成像特征仅限于年轻、热、大质量的行星，它们的轨道离恒星相对较远。这样的行星是可以观测到的，因为它们在形成后继续冷却时产生了固有的自发光。如果可以改善内部工作角度，可以观测到更多的行星。此外，提高高对比度成像的灵敏度极限将使更微弱、质量更低的行星的特征化成为可能。实现更灵敏的后处理的关键是在现代高对比度成像系统中使用波前传感器套件（wfs）同时记录的数据。这些包括主要的高阶WFS以及日冕低阶和焦平面WFS。在博士后研究员的协助下，研究人员将基于现有的概念证明实现算法，用实验室和天空数据测试和验证这些算法，并在MagAO-X和SCExAO仪器上部署软件系统。这两种极端ao日冕仪共享一个通用的软件框架，并且仪器团队之间存在协作。该系统将部署，以便用户可以使用它来减少他们的数据，以达到尽可能高的灵敏度在小的分离。将基于遥测技术的后处理系统应用于当前发电仪器将大大提高其灵敏度。该奖项反映了美国国家科学基金会的法定使命，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。