Tests of the adaptive optical system with a modified correlation sensor at the big solar vacuum telescope

摘要

The possibility of applying adaptive correction to ground-based solar astronomy is considered. Several experimental systems for image stabilization are described along with the results of their tests. As a result of the installation of the first order adaptive-optics system, the Big Solar Vacuum Telescope (BSVT) acquired the new quality. Different ways of development of an adaptive correction to be used in the BSVT of the Baikal Astrophysical Observatory are discussed. Tests of the modified correlation sensor (MCS) at BSVT have shown that at a proper choice of the filtering function parameters, the MCS reliably measures shifts of the solar granulation image in the telescope first focus under good visibility conditions. The MCS, as a part of the adaptive optical system, was intended for measuring the image shift in the telescope second focus. It turned out that the image quality becomes noticeably worse at image transfer to the second focus. The MCS measures the image shift of solar granulation in the second focus only under extremely good visibility conditions and certain granulation structure. Reduction of the telescope entrance aperture to 170 mm insignificantly affects the image quality and, therefore, the MCS operation.