Share Email Print

Proceedings Paper

Experimental study of the effect of non-Kolmogorov stratospheric turbulence on star image motion
Author(s): Mikhail S. Belen'kii; Stephen J. Karis; James M. Brown; Robert Q. Fugate
Format Member Price Non-Member Price
PDF $14.40 $18.00

Paper Abstract

The effect of non-Kolmogorov stratospheric turbulence on star image motion is for the first time experimentally investigated with a ground-based telescope. A new approach permitting isolation of star image motion induced solely by atmospheric turbulence is employed. In this technique Polaris image wander is recorded with the telescope bolted in place to minimize uncontrolled telescope motion. High resolution temporal and spatial statistics of wave-front tilt are obtained. The dependencies of tilt variance, tilt power spectra, and tilt temporal correlation on telescope diameter are investigated for five apertures in the range 0.1-1.5 m. The experimental data show the dependence of tilt variance on telescope diameter does not follow the predictions of the Kolmogorov and von Karman models. The graph of the measured dependence has a “knee” which can be explained only by assuming a non-Kolmogorov stratospheric turbulence effect. The difference between tilt components in different axes indicates anisotropy in stratospheric turbulent inhomogeneities. The slopes of the measured tilt power spectra, approximately -1 in the low frequency range and -8/3 in the high frequency range, do not agree with theoretical predictions. The measured tilt temporal correlation scale is in the range 0.1-1.0 s, and the behavior of the correlation coefficients indicates the effect of large scale inhomogeneities not predicted by the conventional model. Uncontrolled telescope motion is manifested as a “bump” in the tilt power spectra in the range 70-90 Hz, but this makes an insignificant contribution to Polaris jitter variance.

Paper Details

Date Published: 17 October 1997
PDF: 11 pages
Proc. SPIE 3126, Adaptive Optics and Applications, (17 October 1997); doi: 10.1117/12.290143
Show Author Affiliations
Mikhail S. Belen'kii, Georgia Tech Research Institute (United States)
Stephen J. Karis, Air Force Phillips Lab. (United States)
James M. Brown, Air Force Phillips Lab. (United States)
Robert Q. Fugate, Air Force Phillips Lab. (United States)

Published in SPIE Proceedings Vol. 3126:
Adaptive Optics and Applications
Robert K. Tyson; Robert Q. Fugate, Editor(s)

© SPIE. Terms of Use
Back to Top