Comparative study of the flare-burst association for post-maximum periods of consecutive solar cycles

Abstract

The occurrence of microwave bursts and peak flux spectra were studied as a function of the pre-and postmaximum phase of the respective flares during two consecutive solar cycles (1969-1972 and 1980-1982). In the 20th solar cycle, about 76 percent of the flare-associated bursts occurred in the premaximum phase and the remaining 24 percent occurred in the postmaximum phase; in the 21st cycle, these values were 65 and 35 percent, respectively. Bursts with impulsive and gradual rises and falls were relatively more abundant in the premaximum phases for the 20th cycle; impulsive, complex, and simple bursts were more abundant in the 21st cycle.