Experiments on high-resolution observations of the Sun at the A.B. Severny Solar Tower Telescope of CrAO
The paper describes the experiments on high-resolution observations of the Sun, which were carried out during October and November 2021 at the A.B. Severny Solar Tower Telescope (STT-1). The spatial resolution of optical telescopes is usually limited by the seeing. Meanwhile, mathematical methods of speckle imaging allow one to achieve the diffraction-limited resolution. Our goal is to reveal whether STT-1 is capable of producing high-resolution images. We complemented the optical layout of STT-1 by a high-speed imaging unit. The unit made it possible to acquire dozens of short-exposure solar surface images per second. Then the data were processed and compared with the images taken by a space-borne instrument. We found that this technique allows one to substantially increase the spatial resolution of the telescope. Tiny solar features as small as solar granules or penumbra filaments are clearly seen in the reconstructed images. Hence, the data acquired by STT-1 can be used to study the structure and evolution of small-scale features on the Sun in detail.