The conceptual design of GMagAO-X: visible wavelength high contrast imaging with GMT

Jared R. Males; Laird M. Close; Sebastiaan Y. Haffert; Olivier Guyon; Victor Gasho; Fernando Coronado; Olivier Durney; Alexander Hedglen; Maggie Kautz; Jamison Noenickx; John Ford; Tom Connors; Doug Kelly

arXiv · 2208.07312

The conceptual design of GMagAO-X: visible wavelength high contrast imaging with GMT

Jared R. Males·Laird M. Close·Sebastiaan Y. Haffert·Olivier Guyon·Victor Gasho·Fernando Coronado·Olivier Durney·Alexander Hedglen·Maggie Kautz·Jamison Noenickx·John Ford·Tom Connors·Doug Kelly

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Abstract

We present the conceptual design of GMagAO-X, an extreme adaptive optics system for the 25 m Giant Magellan Telescope (GMT). We are developing GMagAO-X to be available at or shortly after first-light of the GMT, to enable early high contrast exoplanet science in response to the Astro2020 recommendations. A key science goal is the characterization of nearby potentially habitable terrestrial worlds. GMagAO-Xis a woofer-tweeter system, with integrated segment phasing control. The tweeter is a 21,000 actuator segmented deformable mirror, composed of seven 3000 actuator segments. A multi-stage wavefront sensing system provides for bootstrapping, phasing, and high order sensing. The entire instrument is mounted in a rotator to provide gravity invariance. After the main AO system, visible (g to y) and near-IR (Y to H) science channels contain integrated coronagraphic wavefront control systems. The fully corrected and, optionally, coronagraphically filtered beams will then be fed to a suite of focal plane instrumentation including imagers and spectrographs. This will include existing facility instruments at GMT via fiber feeds. To assess the design we have developed an end-to-end frequency-domain modeling framework for assessing the performance of GMagAO-X. The dynamics of the many closed-loop feedback control systems are then modeled. Finally, we employ a frequency-domain model of post-processing algorithms to analyze the final post-processed sensitivity. The CoDR for GMagAO-X was held in September, 2021. Here we present an overview of the science cases, instrument design, expected performance, and concept of operations for GMagAO-X.

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Jared R. Males, Laird M. Close, Sebastiaan Y. Haffert, Olivier Guyon, Victor Gasho, Fernando Coronado, Olivier Durney, Alexander Hedglen, Maggie Kautz, Jamison Noenickx, John Ford, Tom Connors, Doug Kelly. 2022-08-15. The conceptual design of GMagAO-X: visible wavelength high contrast imaging with GMT. https://arxiv.org/abs/2208.07312

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