MagAO-X Phase II Upgrades: Implementation and First On-Sky Results of a New Post-AO 1000 Actuator Deformable Mirror

Jay K. Kueny; Kyle Van Gorkom; Maggie Kautz; Sebastiaan Haffert; Jared R. Males; Alex Hedglen; Laird Close; Eden McEwen; Jialin Li; Joseph D. Long; Warren Foster; Logan Pearce; Avalon McLeod; Jhen Lumbres; Olivier Guyon; Joshua Liberman

arXiv · 2407.13019

MagAO-X Phase II Upgrades: Implementation and First On-Sky Results of a New Post-AO 1000 Actuator Deformable Mirror

Jay K. Kueny·Kyle Van Gorkom·Maggie Kautz·Sebastiaan Haffert·Jared R. Males·Alex Hedglen·Laird Close·Eden McEwen·Jialin Li·Joseph D. Long·Warren Foster·Logan Pearce·Avalon McLeod·Jhen Lumbres·Olivier Guyon·Joshua Liberman

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Abstract

MagAO-X is the extreme coronagraphic adaptive optics (AO) instrument for the 6.5-meter Magellan Clay telescope and is currently undergoing a comprehensive batch of upgrades. One innovation that the instrument features is a deformable mirror (DM) dedicated for non-common path aberration correction (NCPC) within the coronagraph arm. We recently upgraded the 97 actuator NCPC DM with a 1000 actuator Boston Micromachines Kilo-DM which serves to (1) correct non-common path aberrations which hamper performance at small inner-working angles, (2) facilitate focal-plane wavefront control algorithms (e.g., electric field conjugation) and (3) enable 10 kHz correction speeds (up from 2 kHz) to assist post-AO, real-time low-order wavefront control. We present details on the characterization and installation of this new DM on MagAO-X as part of our efforts to improve deep contrast performance for imaging circumstellar objects in reflected light. Pre-installation procedures included use of a Twyman-Green interferometer to build an interaction matrix for commanding the DM surface, in closed-loop, to a flat state for seamless integration into the instrument. With this new NCPC DM now installed, we report on-sky results from the MagAO-X observing run in March -- May 2024 for the Focus Diversity Phase Retrieval and implicit Electric Field Conjugation algorithms for quasistatic speckle removal and in-situ Strehl ratio optimization, respectively.

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Jay K. Kueny, Kyle Van Gorkom, Maggie Kautz, Sebastiaan Haffert, Jared R. Males, Alex Hedglen, Laird Close, Eden McEwen, Jialin Li, Joseph D. Long, Warren Foster, Logan Pearce, Avalon McLeod, Jhen Lumbres, Olivier Guyon, Joshua Liberman. 2024-07-17. MagAO-X Phase II Upgrades: Implementation and First On-Sky Results of a New Post-AO 1000 Actuator Deformable Mirror. https://arxiv.org/abs/2407.13019

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