Energetic Particle Responses to Interplanetary Shocks Observed by ACE

At very strong shock passages, protons (and other ions) may be accelerated at or near a spacecraft resulting in substantial particle intensities increases. Such events may be a significant space weather hazard, yet we are still unable to accurately forecast their arrival time or the magnitude of the particle increase. Here, we classify the >10 MeV proton response (observed by ACE/SIS) to passing shocks (identified by ACE/MAG, ACE/SWEPAM, SOHO/PM), examine heavy ion properties, and relate them to the measured shock parameters in an effort to further our understanding of these events and our ability to predict them.