Prediction of the Peak Intensity of Solar Energetic Particle Events in Solar Cycles 23 and 24 using CME Speed and Direction and Radio Observations ("SEPSTER")

Abstract:

We assess whether a formula obtained by Richardson et al. (2014) relating the peak intensity of 14-24 MeV protons in a solar energetic particle event at 1 AU to the solar event location and the speed of the associated coronal mass ejection (CME), may be used to “predict” the intensity of a solar energetic particle event. Starting with a set of all 334 CMEs in the CCMC/SWRC DONKI real-time database during October, 2011-July 2012, selected without consideration of whether they were associated with SEP events, we use the CME speed and direction to predict the proton intensity at Earth or the STEREO spacecraft using this formula. Since most (~85%) of these CMEs were not associated with SEP events, many “false alarms” result. We demonstrate that considering the type II or type III radio emissions that may accompany the CMEs, or the speed and width of the CME, can help to improve the forecast skill, which we assess using several skill scores. The method is also applied to over 1100 CMEs in solar cycle 23.