S-DIMM+ height characterization of day-time seeing using solar granulation
Abstract
To evaluate site quality and to develop multi-conjugative adaptive optics systems for future large solar telescopes, characterization of contributions to seeing from heights up to at least 12 km above the telescope is needed. We describe a method for evaluating contributions to seeing from different layers along the line-of-sight to the Sun. The method is based on Shack Hartmann wavefront sensor data recorded over a large field-of-view with solar granulation and uses only measurements of differential image displacements from individual exposures, such that the measurements are not degraded by residual tip-tilt errors. We conclude that the proposed method allows good measurements when Fried's parameter r_0 is larger than about 7.5 cm for the ground layer and that these measurements should provide valuable information for site selection and multi-conjugate development for the future European Solar Telescope. A major limitation is the large field of view presently used for wavefront sensing, leading to uncomfortably large uncertainties in r_0 at 30 km distance.
Keywords
Cite
@article{arxiv.1002.3151,
title = {S-DIMM+ height characterization of day-time seeing using solar granulation},
author = {G. B. Scharmer and T. I. M. van Werkhoven},
journal= {arXiv preprint arXiv:1002.3151},
year = {2013}
}
Comments
Accepted by AA 22/01/2010 (12 pages, 11 figures)