Vol. 38, issue 07, article # 12

Abstract:

The present work develops a technique for measuring the intensity of atmospheric optical turbulence in crossed optical beams. A new calibration function is suggested which allows estimating vertical profiles of the structure characteristic of the air refractive index turbulent fluctuations using covariance functions of differential jitters of solar subimage fragments detected by Shack–Hartmann sensor. Using observational data obtained at the Large Solar Vacuum Telescope (LSVT) of the Baikal Astrophysical Observatory (BAO), a characteristic vertical profile of the structure characteristic of the air refractive index turbulent fluctuations was measured. For comparison, the vertical profile of the structure characteristic of the air refractive index turbulent fluctuations was calculated based on the mean meteorological atmospheric characteristics. Both modeling and measurement data indicate the existence of turbulent layers at certain altitudes above the LSVT. The suggested approaches can be used in the optimization of adaptive optics systems, as well as in the development of optical turbulence profilers.

Keywords:

atmosphere, turbulence, outer turbulence scale

Figures:

References:

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