Solar electron events from 1995 to 2005 with WIND/3DP

After taking into account times of high background, the corrected occurrence frequency of solar electron events versus peak flux exhibits a power-law distribution over three orders of magnitude with exponents between -1.0 and -1.6 for different years, comparable to the frequency distribution of solar proton events, microflares, and coronal mass ejections (CMEs), but significantly flatter than that of soft X-ray (SXR) flares.

At 40keV (2.8keV), the integrated occurrence rate above ~0.29 (~330)/cm2/s.sr^-1^/keV near 1 AU is ~1000/year (~600/year) at solar maximum and ~35/year (~25/year) at solar minimum, about an order of magnitude larger than the observed occurrence rate. We find these events typically extend over ~45{deg} in longitude, implying the occurrence rate over the whole Sun is ~10^4^/year near solar maximum. The observed solar electron events have a 98.75% association with type III radio bursts, suggesting all type III bursts may be associated with a solar electron event.