EDP Sciences
Free Access
Volume 400, Number 3, March IV 2003
Page(s) 1199 - 1207
Section Physical and chemical processes
DOI https://doi.org/10.1051/0004-6361:20030022

A&A 400, 1199-1207 (2003)
DOI: 10.1051/0004-6361:20030022

Tilt anisoplanatism in laser-guide-star-based multiconjugate adaptive optics

Reconstruction of the long exposure point spread function from control loop data
R. C. Flicker1, 2, F. J. Rigaut2 and B. L. Ellerbroek2

1  Lund Observatory, Box 43, 22100 Lund, Sweden
2  Gemini Observatory, 670 N. A'Ohoku Pl., Hilo HI-96720, USA

(Received 22 August 2002 / Accepted 6 January 2003 )

A method is presented for estimating the long exposure point spread function (PSF) degradation due to tilt anisoplanatism in a laser-guide-star-based multiconjugate adaptive optics systems from control loop data. The algorithm is tested in numerical Monte Carlo simulations of the separately driven low-order null-mode system, and is shown to be robust and accurate with less than 10% relative error in both  H and K bands down to a natural guide star (NGS) magnitude of mR=21, for a symmetric asterism with three NGS on a 30 arcsec radius. The H band limiting magnitude of the null-mode system due to NGS signal-to-noise ratio and servo-lag was estimated previously to mR=19. At this magnitude, the relative errors in the reconstructed PSF and Strehl are here found to be less than 5% and 1%, suggesting that the PSF retrieval algorithm will be applicable and reliable for the full range of operating conditions of the null-mode system.

Key words: Instrumentation -- adaptive optics -- methods -- statistical

Offprint request: R. C. Flicker, ralf@astro.lu.se

© ESO 2003

Current usage metrics show cumulative count of Article Views (full-text article views including HTML views, PDF and ePub downloads, according to the available data) and Abstracts Views on Vision4Press platform.

Data correspond to usage on the plateform after 2015. The current usage metrics is available 48-96 hours after online publication and is updated daily on week days.

Initial download of the metrics may take a while.