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Information × Registration Number 0221U101192, 0120U105433 , R & D reports Title Optical observations of the solar atmosphere and investigations of the influence of wave processes in it on convection popup.stage_title Head Shchukina Nataliia H., Доктор фізико-математичних наук Registration Date 17-01-2021 Organization Main Astronomical Observatory of the National Academy of Sciences of Ukraine popup.description2 Observations of the line intensity profile variations during the extreme minimum of the current 24th cycle of the solar activity were performed with high spectral and temporal resolution using Ernest Gurtovenko telescope of the Main Astronomical Observatory of the NAS of Ukraine. The aim of the observations is to detect the changes in the atmosphere of the quiet Sun during the 11-year cycle of solar activity and to understand the nature of these changes. The influence of sound waves on convection has been studied using high-quality ground-based observations of the faculae regions near the center of the solar disk that were obtained in November 2007 at the German Vacuum Tower Telescope (Tenerife, Spain). Three simultaneous data sets were used simultaneously. They are: 1) spectropolarimetric data in Fe 1564.3-1565.8 nm lines; 2) filtergrams in BaII 455.37-455.43 nm; 3) filtergrams in Ca II H 396.8 nm. It is shown that sound waves which propagate downward from the chromosphere to the photosphere of faculae regions can significantly affect the temperature characteristics of turbulent vortices at the height of continuum spectrum formation. In particular, the contrast of granules can increase by 80%. The morphology of the active region NOAA 9087 and the double-ribbon flare 3N/M6.4 which occurred in July 19 2000 was studied. The development of a circular flare was analyzed using observations in Hα line. The study is based on multiwavelength space (Yohkoh, GOES, SOHO) and ground-based observations (Big Bear and Medon observatories).   Product Description popup.authors Kostik Roman I. Osipov Sergiy M. Chornogor Svetlanaна M. popup.nrat_date 2021-01-17 Close