@inbook{4375fd2e51ef46c48c683c3ca1d49938,
title = "Cornelis Zwaan, open principle, and the future of high-resolution solar telescopes",
abstract = "It was in the years around 1970 that during site-test campaigns for JOSO masts were erected up till 30 m height with sensors at several heights for the measurement of temperature fluctuations. Cornelis (Kees) Zwaan discovered that the fluctuations decrease drastically at heights from about 15 m and upward when there is some wind. The conclusion from this experience was the open telescope principle: the telescope should be completely free in the air 15 m or more above the ground. The Dutch Open Telescope (DOT) was the pioneering demonstrator of the open-telescope technology. Now that larger high-resolution telescopes come in view, it is time to analyze again the principle: (i) the essentials for proper working of the open principle; (ii) the differences with nighttime observations particularly concerning the seeing; (iii) the design consequences for the new generation of high-resolution solar telescopes.",
author = "R.H. Hammerschlag and F.C.M. Bettonvil and A.P.L. J{\"a}gers and G. Sliepen",
year = "2008",
language = "Undefined/Unknown",
series = "Proceedings of SPIE",
publisher = "SPIE",
number = "7012",
pages = "70120M",
editor = "L.M. Stepp and R. Gilmozzi",
booktitle = "Ground-based and Airborne Telescopes II",
address = "United States",
}