The Optical and Mechanical Design for the 21,000 Actuator ExAO System for the Giant Magellan Telescope: GMagAO-X

Laird M. Close; Jared R. Males; Olivier Durney; Fernando Coronado; Sebastiaan Y. Haffert; Victor Gasho; Alexander Hedglen; Maggie Y. Kautz; Tom E. Connors; Mark Sullivan; Olivier Guyon; Jamison Noenickx

arXiv · 2208.07318

The Optical and Mechanical Design for the 21,000 Actuator ExAO System for the Giant Magellan Telescope: GMagAO-X

Laird M. Close·Jared R. Males·Olivier Durney·Fernando Coronado·Sebastiaan Y. Haffert·Victor Gasho·Alexander Hedglen·Maggie Y. Kautz·Tom E. Connors·Mark Sullivan·Olivier Guyon·Jamison Noenickx

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Abstract

GMagAO-X is the near first light ExAO coronagraphic instrument for the 25.4m GMT. It is designed for a slot on the folded port of the GMT. To meet the strict ExAO fitting and servo error requirement (<90nm rms WFE), GMagAO-X must have 21,000 actuator DM capable of >2KHz correction speeds. To minimize wavefront/segment piston error GMagAO-X has an interferometric beam combiner on a vibration isolated table, as part of this "21,000 actuator parallel DM". Piston errors are sensed by a Holographic Dispersed Fringe Sensor (HDFS). In addition to a coronagraph, it has a post-coronagraphic Lyot Low Order WFS (LLOWFS) to sense non-common path (NCP) errors. The LLOWFS drives a non-common path DM (NCP DM) to correct those NCP errors. GMagAO-X obtains high-contrast science and wavefront sensing in the visible and/or the NIR. Here we present our successful externally reviewed (Sept. 2021) CoDR optical-mechanical design that satisfies GMagAO-X's top-level science requirements and is compliant with the GMT instrument requirements and only requires COTS parts.

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Laird M. Close, Jared R. Males, Olivier Durney, Fernando Coronado, Sebastiaan Y. Haffert, Victor Gasho, Alexander Hedglen, Maggie Y. Kautz, Tom E. Connors, Mark Sullivan, Olivier Guyon, Jamison Noenickx. 2022-08-15. The Optical and Mechanical Design for the 21,000 Actuator ExAO System for the Giant Magellan Telescope: GMagAO-X. https://arxiv.org/abs/2208.07318

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