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arXiv · 2407.13021

High-contrast imaging at first-light of the GMT: the wavefront sensing and control architecture of GMagAO-X

Sebastiaan Y. Haffert·Jared R Males·Laird M. Close·Maggie Y. Kautz·Olivier Durney·Olivier Guyon
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Abstract

The Giant Magellan Adaptive Optics eXtreme (GMagAO-X) instrument is a first-light high-contrast imaging instrument for the Giant Magellan Telescope (GMT). GMagAO-X's broad wavelength range and the large 25-meter aperture of the GMT creates new challenges: control of all 21.000 actuators; phasing GMT's segmented primary mirror to nm levels; active control of atmospheric dispersion to sub milli-arcsecond residuals; no chromatic pupil shear to minimize chromatic compensation errors; integrated focal plane wavefront sensing and control (WFSC). GMagAO-X will have simultaneous visible and infra-red WFS channels to control the 21.000 actuator DM. The infra-red arm will be flexible by incorporating switchable sensors such as the pyramid or Zernike WFS. One innovation that we developed for GMagAO-X is the Holographic Dispersed Fringe Sensor that measures differential piston. We have also developed several integrated coronagraphic wavefront sensors to control non-common path aberrations exactly where we need to sense them. We will discuss the key components of the WFSC strategies for GMagAO-X that address the challenges posed by the first high-contrast imaging system on the ELTs.

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Sebastiaan Y. Haffert, Jared R Males, Laird M. Close, Maggie Y. Kautz, Olivier Durney, Olivier Guyon. 2024-07-17. High-contrast imaging at first-light of the GMT: the wavefront sensing and control architecture of GMagAO-X. https://arxiv.org/abs/2407.13021

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