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arXiv · 2208.01155

The space coronagraph optical bench (SCoOB): 2. wavefront sensing and control in a vacuum-compatible coronagraph testbed for spaceborne high-contrast imaging technology

Kyle Van Gorkom·Ewan S. Douglas·Jaren N. Ashcraft·Sebastiaan Haffert·Daewook Kim·Heejoo Choi·Ramya M. Anche·Jared R. Males·Kian Milani·Kevin Derby·Lori Harrison·Olivier Durney
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Abstract

The 2020 Decadal Survey on Astronomy and Astrophysics endorsed space-based high contrast imaging for the detection and characterization of habitable exoplanets as a key priority for the upcoming decade. To advance the maturity of starlight suppression techniques in a space-like environment, we are developing the Space Coronagraph Optical Bench (SCoOB) at the University of Arizona, a new thermal vacuum (TVAC) testbed based on the Coronagraphic Debris Exoplanet Exploring Payload (CDEEP), a SmallSat mission concept for high contrast imaging of circumstellar disks in scattered light. When completed, the testbed will combine a vector vortex coronagraph (VVC) with a Kilo-C microelectromechanical systems (MEMS) deformable mirror from Boston Micromachines Corp (BMC) and a self-coherent camera (SCC) with a goal of raw contrast surpassing $10^{-8}$ at visible wavelengths. In this proceedings, we report on our wavefront sensing and control efforts on this testbed in air, including the as-built performance of the optical system and the implementation of algorithms for focal-plane wavefront control and digging dark holes (regions of high contrast in the focal plane) using electric field conjugation (EFC) and related algorithms.

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Kyle Van Gorkom, Ewan S. Douglas, Jaren N. Ashcraft, Sebastiaan Haffert, Daewook Kim, Heejoo Choi, Ramya M. Anche, Jared R. Males, Kian Milani, Kevin Derby, Lori Harrison, Olivier Durney. 2022-08-01. The space coronagraph optical bench (SCoOB): 2. wavefront sensing and control in a vacuum-compatible coronagraph testbed for spaceborne high-contrast imaging technology. https://arxiv.org/abs/2208.01155

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