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Information × Registration Number 0205U007156, 0103U007923 , R & D reports Title Helioseismological investigation of insides and atmosphere of the Sun by space stations SOHO, CORONAS and ground observations popup.stage_title Head Osipov S.M., Registration Date 23-12-2005 Organization Main Astronomical Observatory popup.description2 The time series of 228-hour observations of solar irradiance performed using the photometer DIFOS aboard the Ukrainian-Russian satellite CORONAS-I have been analyzed. The scientific goal is to investigate amplitudes and phases of the low-degree p-modes of 5-minute solar oscillations. The results obtained are in a good agreement with the SOHO-Virgo/SPM space experiment. The oscillation power is shown to be larger in the ultraviolet spectral band. The power increases with the atmospheric height. It is particularly large for the radial modes. The dependence of phase shifts on the degree of modes is found. The similar data is obtained using SOHO experiment. The phase shifts reach maximum at frequencies around 3.5 - 3.6 mHz. The monotonic changing of phase shifts with height is broken in the lower photosphere and in upper layers near 150-200 km. Earlier this result was never known. The ground-based observations of the irradiance and velocity oscillations have been carried out simultaneously using the solar telescopes of the Instituto de Astrofisica de Canarias (Tenerife and La Palma, Spain). Theoretical investigations of the propagation of waves in the inhomogeneous atmosphere with granulation structure had been carried out. They reproduce rather well the irradiance amplitudes while the calculated phase shifts are in worse agreement with observations. Interaction of the solar convective motions and resonance oscillations have been studied. The damping of the oscillations is negligible in the intergranular lanes while in sunspots is noticeable.5635 Product Description popup.authors popup.nrat_date 2020-04-02 Close