The time profile of relativistic solar particle events as observed by neutron monitors

The most energetic particles accelerated in solar eruptive events are protons and nuclei with energies that may reach a few tens of GeV. They can be detected on the Earth through secondaries they produce when interacting atmosphere. Solar particle where this happens called Ground-Level Enhancements (GLEs). Their study is relevant one hand because high pose particularly strong challenges to understanding acceleration processes. On other hand, secondary constitute source radiation atmosphere temporarily exceed permanent dose rate from galactic cosmic rays. This makes monitoring doses received by aircrew GLEs issue space weather services for civil aviation. addresses time profiles GLEs, search commonalities used constrain models propagation forecast evolution an ongoing event. We investigate historical (1971–2012) worldwide network neutron monitors, comparing rise decay as observed monitor strongest response. sample comprises 23 events. evaluate statistical correlations between inferred fits compute normalised median GLE profile. An empirical correlation reported earlier work times count confirmed. find indications relationship parent activity. discuss ideas mechanisms behind its usefulness services.