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arXiv · 1901.04050

Key Technologies for the Wide Field Infrared Survey Telescope Coronagraph Instrument

Abstract

The Wide Field Infrared Survey Telescope (WFIRST) Coronagraph Instrument (CGI) is a high-contrast imager and integral field spectrograph that will enable the study of exoplanets and circumstellar disks at visible wavelengths. Ground-based high-contrast instrumentation has fundamentally limited performance at small working angles, even under optimistic assumptions for 30m-class telescopes. There is a strong scientific driver for better performance, particularly at visible wavelengths. Future flagship mission concepts aim to image Earth analogues with visible light flux ratios of more than 10^10. CGI is a critical intermediate step toward that goal, with a predicted 10^8-9 flux ratio capability in the visible. CGI achieves this through improvements over current ground and space systems in several areas: (i) Hardware: space-qualified (TRL9) deformable mirrors, detectors, and coronagraphs, (ii) Algorithms: wavefront sensing and control; post-processing of integral field spectrograph, polarimetric, and extended object data, and (iii) Validation of telescope and instrument models at high accuracy and precision. This white paper, submitted to the 2018 NAS Exoplanet Science Strategy call, describes the status of key CGI technologies and presents ways in which performance is likely to evolve as the CGI design matures.

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Vanessa P. Bailey, Lee Armus, Bala Balasubramanian, Pierre Baudoz, Andrea Bellini, Dominic Benford, Bruce Berriman, Aparna Bhattacharya, Anthony Boccaletti, Eric Cady, Sebastiano Calchi Novati, Kenneth Carpenter, David Ciardi, Brendan Crill, William Danchi, John Debes, Richard Demers, Kjetil Dohlen, Robert Effinger, Marc Ferrari, Margaret Frerking, Dawn Gelino, Julien Girard, Kevin Grady, Tyler Groff, Leon Harding, George Helou, Avenhaus Henning, Markus Janson, Jason Kalirai, Stephen Kane, N. Jeremy Kasdin, Matthew Kenworthy, Brian Kern, John Krist, Jeffrey Kruk, Anne Marie Lagrange, Seppo Laine, Maud Langlois, Herve Le Coroller, Chris Lindensmith, Patrick Lowrance, Anne-Lise Maire, Sangeeta Malhotra, Avi Mandell, Michael McElwain, Camilo Mejia Prada, Bertrand Mennesson, Tiffany Meshkat, Dwight Moody, Patrick Morrissey, Leonidas Moustakas, Mamadou N'Diaye, Bijan Nemati, Charley Noecker, Roberta Paladini, Marshall Perrin, Ilya Poberezhskiy, Marc Postman, Laurent Pueyo, Solange Ramirez, Clement Ranc, Jason Rhodes, A. J. E. Riggs, Maxime Rizzo, Aki Roberge, Daniel Rouan, Joshua Schlieder, Byoung-Joon Seo, Stuart Shaklan, Fang Shi, Remi Soummer, David Spergel, Karl Stapelfeldt, Christopher Stark, Motohide Tamura, Hong Tang, John Trauger, Margaret Turnbull, Roeland van der Marel, Arthur Vigan, Benjamin Williams, Edward J. Wollack, Marie Ygouf, Feng Zhao, Hanying Zhoud, Neil Zimmerman. 2019-01-13. Key Technologies for the Wide Field Infrared Survey Telescope Coronagraph Instrument. https://arxiv.org/abs/1901.04050

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