Delta-sunspots and X-class flares

All-sunspots from September 1986 to December 1992 in solar cycle 22 are used to investigate the characteristics of-sunspots and the relationship between-sunspots and X-class X-ray flares. The main results of this statistical study are as follows.

(1)	The earlier discoveries on the formation and disintegration patterns of-sunspots (Tang, 1983; Zirin and Liggett, 1987; Zirin, 1988) are confirmed. In a general sense, all-sunspots form from the penetration of two different dipoles. Delta-sunspots could be disintegrated byin situ flux cancellation. In addition, some-sunspots become separated by the sliding apart of opposite polarities.
(2)	A prominent characteristic of-sunspots is the imbalanced flux between the two polarities. A sample of 58-sunspots observed by the Solar Magnetic Field Telescope at Huairou, in which there are one or more X-class flares, maintains an average flux ratio of 6.6 between the majority and minority polarities. Unlike the early results of Tang (1983), two-third of them show a dominant flux from the preceding spots.
(3)	The number of-sunspots seems to be an index of solar activity. More than 95% of X-class X-ray flares take place in active regions of-sunspots; while 23% of-sunspots are generators of X-class X-ray flares. The productivity of X-class flares is closely correlated to the lifetime of-sunspots in this manner:Pxxf = –0.12 + 0.02TEmphasis>/2.