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  • Accepted Manuscript: Evaluating the performance of the Keck Observatory adaptive optics systems on crowded field data using different adaptive optics configurations

This content will become publicly available on September 7, 2023

Title: Evaluating the performance of the Keck Observatory adaptive optics systems on crowded field data using different adaptive optics configurations
We present evaluations of the Keck Telescope’s adaptive optics (AO) performance on Milky Way Galactic center imaging and spectroscopic observations using three different AO setups: laser guide star with infrared (IR) tip-tilt correction, laser guide star with visible tip-tilt correction, and infrared natural guide star with a pyramid wavefront sensor. Observations of the Galactic Center can utilize a bright IR tip-tilt star (K′ = 7.4 mag) for corrections, which is over 10 arcseconds closer than the optical tip-tilt star. The proximity of this IR star enables the comparison of the aforementioned AO configurations. We present performance metrics such as full-width-at-half-maximum (FWHM), Strehl ratio, and spectral signal to noise ratio and their relations to atmospheric seeing conditions. The IR tip-tilt star decreases the median spatial FWHM by 31% in imaging data and 30% in spectroscopy. Median Strehl for imaging data improves by 24%. Additionally, the IR star removes the seeing dependence from differential tip-tilt error in both imaging and spectroscopic data. This evaluation provides important work for ongoing upgrades to AO systems, such as the Keck All sky Precision Adaptive Optics (KAPA) upgrade on the Keck I Telescope, and the development of new AO systems for extremely large telescopes.
Authors:
; ; ; ; ; ; ; ; ; ;
Editors:
Schmidt, Dirk; Schreiber, Laura; Vernet, Elise
Award ID(s):
2108185
Publication Date:
NSF-PAR ID:
10356650
Journal Name:
Adaptive Optics Systems VIII
Volume:
12185
Page Range or eLocation-ID:
1218545
Sponsoring Org:
National Science Foundation
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