SLODAR: measuring optical turbulence altitude with a Shack-Hartmann wavefront sensor

Wilson, R.W.

Abstract

This paper discusses the use of Shack–Hartmann wavefront sensors to determine the vertical distribution of atmospheric optical turbulence above large telescopes. It is demonstrated that the turbulence altitude profile can be recovered reliably from time-averaged spatial cross-correlations of the local wavefront slopes for Shack–Hartmann observations of binary stars. The method, which is referred to as SLODAR, is analogous to the well known SCIDAR scintillation profiling technique, and a calibration against contemporaneous SCIDAR observations is shown. Hardware requirements are simplified relative to the scintillation method, and the number of suitable target objects is larger. The implementation of a Shack–Hartmann based turbulence monitor for use at the William Herschel Telescope is described. The system will be used to optimize adaptive optical observations at the telescope and to characterize anisoplanatic variations of the corrected point spread function.

Citation

Wilson, R. (2002). SLODAR: measuring optical turbulence altitude with a Shack-Hartmann wavefront sensor. Monthly Notices of the Royal Astronomical Society, 337(1), 103-108. https://doi.org/10.1046/j.1365-8711.2002.05847.x

• Journal Article Type: Article
• Publication Date: 2002-11
• Deposit Date: Nov 22, 2006
• Journal: Monthly Notices of the Royal Astronomical Society
• Print ISSN: 0035-8711
• Electronic ISSN: 1365-2966
• Publisher: Royal Astronomical Society
• Peer Reviewed: Peer Reviewed
• Volume: 337
• Issue: 1
• Pages: 103-108
• DOI: https://doi.org/10.1046/j.1365-8711.2002.05847.x
• Keywords: Atmospheric effects, Instrumentation, Adaptive optics, Site testing, Telescopes.
• Public URL: https://durham-repository.worktribe.com/output/1616090