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

对太阳系外行星进行成像是一项挑战。行星通常比它们的宿主恒星暗十万到一百亿倍。拍摄这些行星的照片需要近乎完美的光线控制。星光被称为“日冕仪”的光学装置阻挡。地面望远镜必须处理地球大气层中湍流的额外问题。湍流导致恒星闪烁，望远镜使用一种称为“自适应光学”的技术消除这种闪烁。最后，进行图像处理以在噪声中找到系外行星信号。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。这造成了许多偏见和假象。在靠近星星的地方尤其如此，在那里可以找到大多数行星。这个项目的目标是通过使用所有的综合信息来找到更多的行星。将为两个现有的仪器编写软件，天文学家将使用这些仪器来分析他们的图像。该软件将编写成易于使用，并免费提供给天文学家。到目前为止，对系外行星的直接成像表征仅限于年轻、热、大质量的行星，它们的轨道距离恒星相对较远。这类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内在的自发光。如果可以改善内工作角，可以观察到更多的行星。此外，提高高对比度成像的灵敏度极限将使更暗，质量更低的行星的特征。 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由波前传感器（WFS）套件同时记录的数据。这些包括主要的高阶WFS以及日冕物质抛射的低阶和焦平面WFS。在博士后研究人员的协助下，研究人员将根据现有的概念证明实施算法，使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冠状照相仪器共享一个共同的软件框架，仪器团队之间进行协作。该系统的部署将使用户可以使用它来减少数据，以实现小间隔的最高可能灵敏度。在当前一代仪器上提供基于遥测的后处理系统将大大提高其灵敏度。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。

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.