Simultaneous observations of the H-alpha and Ca II K floccular lines show that during the first three days of the newly formed flocculi the temperature grows gradually, while the density is practically constant. During the following days an increase in density is observed, The phase of increasing density does not occur in the case of faint flocculi. The K-line analysis of the six newly - formed sunspots indicates that the average cooling upward velocity equals 15 ms”' . An increase in sunspot induction was observed at the time of the flares (46 spots, Fig. 5).
We describe the course of events during the evolution of the 300 keV, 3B/M7 June 26, 1983, 14:07 UT flare, as observed at the Crimean Astrophysical Observatory. We show directly as they developed a/ preflare microprominence uprise (Fig. 1)
b/ emisslve-surge flare onset c/ flaring arch system during the maximum flare phase (Fig. 2) d/ flaring arch cooling, which dlffers from the proper "post-flare loops" phenomenon (Fig. 3). The maximum rate of the upward surge’s extension, along its
axis, was 360 km s-1.
The occurrence of LDE flares in the last three solar cycles
has been investigated. Generally, in all the cycles considered, LDE flares mainly originated during a 6-year interval of the respective cycle (2 years before and 4 years after the cycle maximum). The highest LDE flare occurrence was observed in the ascending phase of the 22nd cycle (monthly mean number in 1989 - 32, in 1970 - 19 and in 1980 - 14 LDE (M-X) flares).