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arXiv · 2608.02962

The Space Coronagraph Optical Bench (SCoOB): X. Dark zone maintenance

Saraswathi Kalyani Subramanian·Kyle Van Gorkom·Ramya Anche·William Melby·Kian Milani·Emory Jenkins·Irina Stefan·Adam Schilperoort·Jaren N. Ashcraft·Heejoo Choi·Kevin Derby·Olivier Durney·Daewook Kim·Kelsey Miller·Ewan S. Douglas
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Abstract

The Space Coronagraph Optical Bench (SCoOB) is a vacuum high contrast imaging testbed designed to demonstrate starlight suppression at optical wavelengths and obtain contrasts better than 10$^{-8}$ in a one-sided dark hole from 3 to 10 $\lambda/D$ using a vector vortex coronagraph (VVC) mask. Some of the recent efforts have been in testing dark zone maintenance (DZM) algorithms which are used to stabilize the contrast in the presence of wavefront drifts and allow for the long integration times required by exoplanet observations. In this work, we discuss the results from simulations with two DZM algorithms - linear dark field control (LDFC) and extended Kalman Filter-based (EKF) DZM. We also report preliminary results from the testbed with LDFC.

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Saraswathi Kalyani Subramanian, Kyle Van Gorkom, Ramya Anche, William Melby, Kian Milani, Emory Jenkins, Irina Stefan, Adam Schilperoort, Jaren N. Ashcraft, Heejoo Choi, Kevin Derby, Olivier Durney, Daewook Kim, Kelsey Miller, Ewan S. Douglas. 2026-08-03. The Space Coronagraph Optical Bench (SCoOB): X. Dark zone maintenance. https://arxiv.org/abs/2608.02962

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