PERIODICITY IN THE BASAL COMPONENT OF RADIO-EMISSION DURING MAXIMUM AND MINIMUM SOLAR-ACTIVITY

The basal component of radio emission is the radio intensity obtained after subtracting the sunspot-dependent (magneto-active) component fro m the observed flux and finally deducting the steady part from this su btracted value. The periodicity of this basal component of solar radio emission in the frequency band 0.245-15.4 GHz was studied both for th e solar maximum (1980 and 1991) and minimum (1975 and 1986) periods. A constant periodicity of 35 days was observed in the entire radio band under study during the periods of maximum solar activity, whereas the periodicity fluctuates harmonically with frequency during the minimum periods, giving rise to an average time period of approximately 54 da ys.