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Information × Registration Number 0219U000818, 0118U004070 , R & D reports Title Investigation and interpretation of acoustic oscillations on the Sun using data of space experiments CORONAS-DIFOS (Ukraine), SOHO (USA) and ground-based observations popup.stage_title Head Osipov Sergiy, Registration Date 27-02-2019 Organization Main Astronomical Observatory popup.description2 The systematization of observations data of space gelioseismological experiments Coronas-DIFOS-F, SOHO/Virgo and SOHO/GOLF, primary data processing, error analysis are completed. Algorithms and programs for analysis of amplitude-phase characteristics of five-minute oscillations are developed. The analysis of the spectra of acoustic oscillation power showed a significant increase over time of noise for all frequencies in the range of 1.7-9.9 MHz. Noise velocities have been revealed, in addition, the apparent annual periodicity. The influence of the most powerful solar flares on the characteristics of global five-minute oscillations of the solar photosphere is investigated. It is shown that during the flares the frequency of modes decreases, the power of the modes increases, the background power and the phase dependences of oscillations vary at different altitudes of the Sun's atmosphere. In general, the effect of flares on acoustic oscillations of the Sun is negligible and short-lived and has the opposite character when compared with the effect of the spot activity of the Sun. The analysis of simultaneous, integrated ground observations of quiet and faculae areas of the solar surface has shown that the propagating acoustic waves originate in the lower photosphere both in the active and in the quiet areas of the solar surface, but to achieve and heat the chromosphere these waves are capable only in an active region where moderate magnetic fields are present. Product Description popup.authors Беспалько В.Г. Васильєва І.Е. Костик Р.І. Осіпов С.М. Щукіна Н.Г. popup.nrat_date 2020-04-02 Close