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arXiv · 2012.11667

CHARA Array adaptive optics: complex operational software and performance

Narsireddy Anugu·Theo ten Brummelaar·Nils H. Turner·Matthew D. Anderson·Jean-Baptiste Le Bouquin·Judit Sturmann·Laszlo Sturmann·Chris Farrington·Norm Vargas·Olli Majoinen·Michael J. Ireland·John D. Monnier·Denis Mourard·Gail Schaefer·Douglas R. Gies·Stephen T. Ridgway·Stefan Kraus·Cyril Petit·Michel Tallon·Caroline B. Lim·Philippe Berio
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Abstract

The CHARA Array is the longest baseline optical interferometer in the world. Operated with natural seeing, it has delivered landmark sub-milliarcsecond results in the areas of stellar imaging, binaries, and stellar diameters. However, to achieve ambitious observations of faint targets such as young stellar objects and active galactic nuclei, higher sensitivity is required. For that purpose, adaptive optics are developed to correct atmospheric turbulence and non-common path aberrations between each telescope and the beam combiner lab. This paper describes the AO software and its integration into the CHARA system. We also report initial on-sky tests that demonstrate an increase of scientific throughput by sensitivity gain and by extending useful observing time in worse seeing conditions. Our 6 telescopes and 12 AO systems with tens of critical alignments and control loops pose challenges in operation. We describe our methods enabling a single scientist to operate the entire system.

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Narsireddy Anugu, Theo ten Brummelaar, Nils H. Turner, Matthew D. Anderson, Jean-Baptiste Le Bouquin, Judit Sturmann, Laszlo Sturmann, Chris Farrington, Norm Vargas, Olli Majoinen, Michael J. Ireland, John D. Monnier, Denis Mourard, Gail Schaefer, Douglas R. Gies, Stephen T. Ridgway, Stefan Kraus, Cyril Petit, Michel Tallon, Caroline B. Lim, Philippe Berio. 2020-12-21. CHARA Array adaptive optics: complex operational software and performance. https://doi.org/10.1117/12.2561560

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