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

TL;DR

This paper details the implementation and on-sky testing of a new 1000-actuator deformable mirror in MagAO-X, significantly enhancing its adaptive optics capabilities for high-contrast imaging of circumstellar objects.

Contribution

It introduces a high-actuator-count deformable mirror upgrade for MagAO-X, enabling faster correction speeds and improved non-common path aberration correction.

Findings

Successful installation and characterization of the new DM.

On-sky results demonstrate improved wavefront control performance.

Enhanced contrast and Strehl ratio achieved in recent observations.

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.