Spectrum-time analysis of the radio emission of the sun at λ = 3 cm wavelength.

Observations of solar radio emission at 3 cm were made with the 2 m telescope at the mountain station of the Main Astronomical Observatory near Kislovodsk. Spectrum-time analysis shows oscillations with periods of 5, 10, 15, and 20 min. The oscillation power was found to be periodically attenuated. It is found that, for oscillations with periods of 5 and 10 min, the intensity number and durations of the attenuations decrease prior to flares with an importance not less than 1. However, for periods of 15 and 20 min, the intensity and duration of the attenuations increase 2-4 days prior to the onset of flares.