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arXiv · 2407.00960

Optical turbulence vertical distribution at the Peak Terskol Observatory and Mt. Kurapdag

Abstract

Characterization of atmospheric turbulence is essential to understanding image quality of astronomical telescopes and applying adaptive optics systems. In this study, the vertical distributions of optical turbulence at the Peak Terskol Observatory (43.27472N 42.50083E, 3127 m a.s.l.) using the Era-5 re-analysis, scintillation measurements and sonic anemometer data are investigated. For the reanalysis grid node closest to the observatory, vertical profiles of the structural constant of the air refractive index turbulent fluctuations $C^2_n$ were obtained. The calculated $C^2_n(z)$ vertical profiles are compared with the vertical distribution of turbulence intensity obtained from tomographic measurements with Shack-Hartmann sensor. The Fried parameter r0 at the location of Terskol Peak Observatory was estimated. Using combination of atmospheric models and scheme paramaterization of turbulence, $C^2_n(z)$ profiles at Mt. Kurapdag were obtained. The r0 values at the Peak Terskol Observatory are compared with estimated values of this length at the ten astronomical sites including Ali, Lenghu and Daocheng.

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A. Y. Shikhovtsev, C. Qing, E. A. Kopylov, S. A. Potanin, P. G. Kovadlo. 2024-07-01. Optical turbulence vertical distribution at the Peak Terskol Observatory and Mt. Kurapdag. https://doi.org/10.3390/rs16122102

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