The Solar Tower Telescope TST-2

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The 60-cm coelostat, 45-cm spherical primary mirror (f/27), one flat and two convex secondary mirrors provide f/27, f/46 and f/78 Cassegrain foci on the entrance slit of a spectrograph. There are an echelle-grating, Universal Spectrophotometer with a scanning system and a CCD camera.

Study of spectra with analyzers of circular and linear polarization allowed us to determine physical conditions in solar flares, moustaches and to model active processes and their evolution.

The part of the Sun with coronal hole obtained in the HeI 10830 Å spectral line.

Study of evolution and differential rotation of the solar large - scale background magnetic fields and coronal holes has shown that the background magnetic fields can not be explained by the diffusion of the active region fields and that the nature of coronal holes differs from the nature of the background fields.