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arXiv · 1807.04729

Modeling coronagraphic extreme wavefront control systems for high contrast imaging in ground and space telescope missions

Abstract

The challenges of high contrast imaging (HCI) for detecting exoplanets for both ground and space applications can be met with extreme adaptive optics (ExAO), a high-order adaptive optics system that performs wavefront sensing (WFS) and correction at high speed. We describe two ExAO optical system designs, one each for ground-based telescopes and space-based missions, and examine them using the angular spectrum Fresnel propagation module within the Physical Optics Propagation in Python (POPPY) package. We present an end-to-end (E2E) simulation of the MagAO-X instrument, an ExAO system capable of delivering 6$\times10^{-5}$ visible-light raw contrast for static, noncommon path aberrations without atmosphere. We present a laser guidestar (LGS) companion spacecraft testbed demonstration, which uses a remote beacon to increase the signal available for WFS and control of the primary aperture segments of a future large space telescope, providing on order of a factor of ten factor improvement for relaxing observatory stability requirements. The LGS E2E simulation provides an easily adjustable model to explore parameters, limits, and trade-offs on testbed design and characterization.

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Jennifer Lumbres, Jared Males, Ewan Douglas, Laird Close, Olivier Guyon, Kerri Cahoy, Ashley Carlton, Jim Clark, David Doelman, Lee Feinberg, Justin Knight, Weston Marlow, Kelsey Miller, Katie Morzinski, Emiel Por, Alexander Rodack, Lauren Schatz, Frans Snik, Kyle Van Gorkom, Michael Wilby. 2018-07-12. Modeling coronagraphic extreme wavefront control systems for high contrast imaging in ground and space telescope missions. https://arxiv.org/abs/1807.04729

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