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Title: Fast and furious focal-plane wavefront sensing at W.M. Keck Observatory
High quality, repeatable point-spread functions are important for science cases like direct exoplanet imaging, high-precision astrometry, and high-resolution spectroscopy of exoplanets. For such demanding applications, the initial on-sky point-spread function delivered by the adaptive optics system can require further optimization to correct unsensed static aberrations and calibration biases. We investigated using the Fast and Furious focal-plane wavefront sensing algorithm as a potential solution. This algorithm uses a simple model of the optical system and focal plane information to measure and correct the point-spread function phase, without using defocused images, meaning it can run concurrently with science. On-sky testing demonstrated significantly improved PSF quality in only a few iterations, with both narrow and broadband filters. These results suggest this algorithm is a useful path forward for creating and maintaining high-quality, repeatable on-sky adaptive optics point-spread functions.  more » « less
Award ID(s):
2009051
PAR ID:
10287068
Author(s) / Creator(s):
; ; ; ; ;
Editor(s):
Shaklan, Stuart B.; Ruane, Garreth J.
Date Published:
Journal Name:
Proc. SPIE 11823, Techniques and Instrumentation for Detection of Exoplanets X, 118231E
Page Range / eLocation ID:
36
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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