Validating the proton prediction system (PPS)

The proton prediction system (PPS) is a program developed at the Air Force Research Laboratory (AFRL) to predict solar energetic (E>5MeV) proton (SEP) intensities at 1 AU following solar flares. It is based on average observed SEP intensity-time profiles, peak intensities, and event durations. The input parameters are solar flare peak or time-integrated X-ray or radio fluxes and their times of onsets and maxima, and solar flare locations. We do a limited validation of the PPS using 78 GOES solar X-ray flares of peak intensity ⩾M5⩾M5 with well associated HαHα flare locations. Predicted peak proton intensities J(E>10MeV) and event onset and rise times are compared with SEP events observed by GOES. We also select all GOES E>10MeV SEP events above 10 proton flux units (pfu) during the same time period to compare with those predicted by the PPS. With our M5 X-ray flare threshold the PPS yields approximately equal numbers of correct predictions, false predictions, and missed 10-pfu SEP events.