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arXiv · 1511.01882

Demonstration of high contrast with an obscured aperture with the WFIRST-AFTA shaped pupil coronagraph

Eric Cady·Camilo Mejia Prada·Xin An·Kunjithapatham Balasubramanian·Rosemary Diaz·N. Jeremy Kasdin·Brian Kern·Andreas Kuhnert·Bijan Nemati·Ilya Poberezhskiy·A. J. Eldorado Riggs·Robert Zimmer·Neil Zimmerman
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Abstract

The coronagraph instrument on the WFIRST-AFTA mission study has two coronagraphic architectures, shaped pupil and hybrid Lyot, which may be interchanged for use in different observing scenarios. Each architecture relies on newly-developed mask components to function in the presence of the AFTA aperture, and so both must be matured to a high technology readiness level (TRL) in advance of the mission. A series of milestones were set to track the development of the technologies required for the instrument; in this paper, we report on completion of WFIRST-AFTA Coronagraph Milestone 2---a narrowband $10^{-8}$ contrast test with static aberrations for the shaped pupil---and the plans for the upcoming broadband Coronagraph Milestone 5.

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Eric Cady, Camilo Mejia Prada, Xin An, Kunjithapatham Balasubramanian, Rosemary Diaz, N. Jeremy Kasdin, Brian Kern, Andreas Kuhnert, Bijan Nemati, Ilya Poberezhskiy, A. J. Eldorado Riggs, Robert Zimmer, Neil Zimmerman. 2015-11-05. Demonstration of high contrast with an obscured aperture with the WFIRST-AFTA shaped pupil coronagraph. https://doi.org/10.1117/1.jatis.2.1.011004

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