The Santa Cruz Extreme AO Lab (SEAL) 2.0: A reflective, multi-wavelength rebuild

Rebecca Jensen-Clem; Vincent Chambouleyron; Prince Javier; Daren Dillon; Emiel H. Por; Benjamin Calvin; Sylvain Cetre; Rodrigo Amezcua Correa; Tara Crowe; Jordan Diaz; Caleb Dobias; David Doelman; Stephen Eikenberry; J. Fowler; Benjamin L. Gerard; Phil Hinz; Renate Kupke; Ashai Moreno; Tiffany Nguyen; Maissa Salama; Aditya R. Sengupta; Nour Skaf; Frans Snik

arXiv · 2509.03770

The Santa Cruz Extreme AO Lab (SEAL) 2.0: A reflective, multi-wavelength rebuild

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Abstract

The Santa cruz Extreme Adaptive optics Lab (SEAL) is a visible/near-infrared wavelength testbed designed to support technology development for high contrast imaging on large, segmented, ground-based telescopes. SEAL saw first light in 2021 as a transmissive, visible-wavelength AO testbed. In this paper, we present four major upgrades to SEAL: (1) the testbed has been rebuilt with custom off-axis parabolic mirrors, enabling operation in both near-infrared and visible wavelengths; (2) the suite of wavefront sensors now includes a Shack-Hartmann, transmissive four-sided pyramid, vector-Zernike, and, in the muirSEAL testbed, a photonic lantern; (3) the testbed includes a vector-vortex coronagraph and will soon include a hybrid astrophotonic coronagraph; (4) in addition to its original Keck-heritage RTC, SEAL now includes two additional control software packages: Catkit, originally developed for the HiCAT testbed at the Space Telescope Science Institute, and the RTC Compute And Control for Adaptive Optics (CACAO), originally designed for Subaru/SCExAO. We discuss the performance of the testbed after the reflective rebuild and on-going technology development work at SEAL.

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Rebecca Jensen-Clem, Vincent Chambouleyron, Prince Javier, Daren Dillon, Emiel H. Por, Benjamin Calvin, Sylvain Cetre, Rodrigo Amezcua Correa, Tara Crowe, Jordan Diaz, Caleb Dobias, David Doelman, Stephen Eikenberry, J. Fowler, Benjamin L. Gerard, Phil Hinz, Renate Kupke, Ashai Moreno, Tiffany Nguyen, Maissa Salama, Aditya R. Sengupta, Nour Skaf, Frans Snik. 2025-09-03. The Santa Cruz Extreme AO Lab (SEAL) 2.0: A reflective, multi-wavelength rebuild. https://arxiv.org/abs/2509.03770

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