Asymmetries in Adaptive Optics Point Spread Functions

Authors

• Alexander Madurowicz, Kavli Institute for Particle Astrophysics and Cosmology
• Bruce Macintosh, Kavli Institute for Particle Astrophysics and Cosmology
• Jeffrey Chilcote, University of Notre Dame
• Marshall Perrin, Space Telescope Science Institute
• Lisa Poyneer, Lawrence Livermore National Laboratory
• Laurent Pueyo, Space Telescope Science Institute
• Jean Baptiste Ruffio, Kavli Institute for Particle Astrophysics and Cosmology
• Vanessa P. Bailey, Jet Propulsion Laboratory
• Travis Barman, The University of Arizona
• Joanna Bulger, National Institutes of Natural Sciences - National Astronomical Observatory of Japan
• Tara Cotten, University of Georgia
• Robert J. De Rosa, Kavli Institute for Particle Astrophysics and Cosmology
• Rene Doyon, Institut de Recherche sur les Exoplanètes
• Gaspard Duchêne, University of California, Berkeley
• Thomas M. Esposito, University of California, Berkeley
• Michael P. Fitzgerald, University of California, Los Angeles
• Katherine B. Follette, Amherst College
• Benjamin L. Gerard, University of Victoria
• Stephen J. Goodsell, Gemini Observatory
• James R. Graham, University of California, Berkeley
• Alexandra Z. Greenbaum, University of Michigan, Ann Arbor
• Pascale Hibon, European Southern Observatory Santiago
• Li Wei Hung, Natural Sounds and Night Skies Division
• Patrick Ingraham, Large Synoptic Survey Telescope
• Paul Kalas, University of California, Berkeley
• Quinn Konopacky, Center for Astrophysics & Space Sciences
• Jérôme Maire, Center for Astrophysics & Space Sciences
• Franck Marchis, SETI Institute
• Mark S. Marley, NASA Ames Research Center
• Christian Marois, National Research Council Canada
• Stanimir Metchev, Western University
• Maxwell A. Millar-Blanchaer, Jet Propulsion Laboratory
• Kimberly Ward-Duong, Arizona State UniversityFollow

Document Type

Article

Publication Date

10-1-2019

Publication Title

Journal of Astronomical Telescopes, Instruments, and Systems

Abstract

An explanation for the origin of asymmetry along the preferential axis of the point spread function (PSF) of an AO system is developed. When phase errors from high-altitude turbulence scintillate due to Fresnel propagation, wavefront amplitude errors may be spatially offset from residual phase errors. These correlated errors appear as asymmetry in the image plane under the Fraunhofer condition. In an analytic model with an open-loop AO system, the strength of the asymmetry is calculated for a single mode of phase aberration, which generalizes to two dimensions under a Fourier decomposition of the complex illumination. Other parameters included are the spatial offset of the AO correction, which is the wind velocity in the frozen flow regime multiplied by the effective AO time delay and propagation distance or altitude of the turbulent layer. In this model, the asymmetry is strongest when the wind is slow and nearest to the coronagraphic mask when the turbulent layer is far away, such as when the telescope is pointing low toward the horizon. A great emphasis is made about the fact that the brighter asymmetric lobe of the PSF points in the opposite direction as the wind, which is consistent analytically with the clarification that the image plane electric field distribution is actually the inverse Fourier transform of the aperture plane. Validation of this understanding is made with observations taken from the Gemini Planet Imager, as well as being reproducible in end-to-end AO simulations.

Keywords

Adaptive optics, Fresnel propagation, Point-spread functions, Scintillation, Turbulence

Volume

5

Issue

4

DOI

https://doi.org/10.1117/1.JATIS.5.4.049003

ISSN

23294124

Version

Version of Record

Recommended Citation

Madurowicz, Alexander; Macintosh, Bruce; Chilcote, Jeffrey; Perrin, Marshall; Poyneer, Lisa; Pueyo, Laurent; Ruffio, Jean Baptiste; Bailey, Vanessa P.; Barman, Travis; Bulger, Joanna; Cotten, Tara; De Rosa, Robert J.; Doyon, Rene; Duchêne, Gaspard; Esposito, Thomas M.; Fitzgerald, Michael P.; Follette, Katherine B.; Gerard, Benjamin L.; Goodsell, Stephen J.; Graham, James R.; Greenbaum, Alexandra Z.; Hibon, Pascale; Hung, Li Wei; Ingraham, Patrick; Kalas, Paul; Konopacky, Quinn; Maire, Jérôme; Marchis, Franck; Marley, Mark S.; Marois, Christian; Metchev, Stanimir; Millar-Blanchaer, Maxwell A.; and Ward-Duong, Kimberly, "Asymmetries in Adaptive Optics Point Spread Functions" (2019). Astronomy: Faculty Publications, Smith College, Northampton, MA.
https://scholarworks.smith.edu/ast_facpubs/117