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arXiv · 2208.02380

A Visible-light Lyot Coronagraph for SCExAO/VAMPIRES

Miles Lucas·Michael Bottom·Olivier Guyon·Julien Lozi·Barnaby Norris·Vincent Deo·Sebastien Vievard·Kyohoon Ahn·Nour Skaf·Peter Tuthill
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Abstract

We describe the design and initial results from a visible-light Lyot coronagraph for SCExAO/VAMPIRES. The coronagraph is comprised of four hard-edged, partially transmissive focal plane masks with inner working angles of 36 mas, 55 mas, 92 mas, and 129 mas, respectively. The Lyot stop is a reflective, undersized design with a geometric throughput of 65.7%. Our preliminary on-sky contrast is 1e-2 at 0.1" to 1e-4 at 0.75" for all mask sizes. The coronagraph was deployed in early 2022 and is available for open use.

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Miles Lucas, Michael Bottom, Olivier Guyon, Julien Lozi, Barnaby Norris, Vincent Deo, Sebastien Vievard, Kyohoon Ahn, Nour Skaf, Peter Tuthill. 2022-08-03. A Visible-light Lyot Coronagraph for SCExAO/VAMPIRES. https://arxiv.org/abs/2208.02380

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