Temporal variability and statistics of the Strehl ratio in adaptive-optics images

Abstract

We have investigated the temporal variability and statistics of the "instantaneous" Strehl ratio. The observations were carried out with the 3.63-m AEOS telescope equipped with a high-order adaptive optics system. In this paper Strehl ratio is defined as the peak intensity of a single short exposure. We have also studied the behaviour of the phase variance computed on the reconstructed wavefronts. We tested the Marechal approximation and used it to explain the observed negative skewness of the Strehl ratio distribution. The estimate of the phase variance is shown to fit a three-parameter Gamma distribution model. We show that simple scaling of the reconstructed wavefronts has a large impact on the shape of the Strehl ratio distribution.

arXiv commentsubmitted to PASP

References in corpus (4)

• Lucky Imaging: High Angular Resolution Imaging in the Visible from the Ground
• Ground-Based Coronagraphy with High Order Adaptive Optics
• Diffraction-limited 800nm imaging with the 2.56m Nordic Optical Telescope
• The Strehl Ratio in Adaptive Optics Images: Statistics and Estimation

Cited by in corpus (4)

• Getting Lucky with Adaptive Optics: Fast AO Image Selection in the Visible with a Large Telescope
• Reference-less detection, astrometry, and photometry of faint companions with adaptive optics
• Stochastic Speckle Discrimination with Time-Tagged Photon Lists: Digging Below the Speckle Noise Floor
• Probing Photon Statistics in Adaptive Optics Images with SCExAO/MEC