18.06.02

III. The spectral and polarization features of solar plasma in a wide frequency range according RATAN-600 data.

•  The aim of the reports is to show the different spectral and polarization features of  radio emission in active and stable  solar structures, The structures were observed with moderate spatial and frequency resolution at RATAN-600. The future progress in the study with the help of FASR can be expected. •At Fig.3 the example of one-dimensional scan with RATAN-600 observation both at one wavelength and many wavelength in the range from 1.8 cm to 17.1 cm is superimposed on the solar disk. •At the Fig.4 and 5 we demonstrate the spectral behaviour of different polarization details in wide wavelength range. •The importance of high flux sensitivity is needed for study of weak polarization signal. This is demonstrated at the Fig. 6, 8 and 9. The high dynamic range using in RATAN observations is shown at Fig. 7. •The Fig. 10, 11, 12 and 13 are devoted to different spectral-polarization features of preflare plasma, which appear in flare-productive active regions before powerful flares. •The interesting effect connected with radioemission depression before flare is demonstrated at Fig 14 (microwave «darkening») and Fig.15 (associated polarization inversion).