Characteristics and regularities of sunspots and flares in GLE events

Abstract In this paper, we have made an effort to study the characteristics and regularities of sunspots and flares associated with the 73 GLE events. The mean (∼ 55.37◦ ± 5.30◦ ) longitude of the GLE-associated-flares in the western hemisphere and the mean (∼ 6.71◦±2.25◦ ) latitude of the GLE-associated-flares in the region near the solar equator or northern hemisphere of the Sun suggested that most of the GLEs originated from the western hemisphere of the Sun. The optical flares associated with GLEs are of magnitude higher than or equal to class 1, while the soft X-ray flares associated with GLEs are of magnitude higher than or equal to class C, with the majority being X-class flares. The rates of increases in GLEs do not have a direct relationship with the maximum and average soft X-ray flux. The time difference between the GLE onsets and the corresponding flare peak times is mainly concentrated within 0-20 minutes. Thus, the study suggests that solar flares are possibly the sources of high energy particles in GLE events.