North/South Hemispheric Periodicities in the >25 MeV Solar Proton Event Rate During the Rising and Peak Phases of Solar Cycle 24

Ian Richardson, Tycho von Rosenvinge, Hilary Cane

We present evidence that $>25$ MeV solar proton events show a clustering in time at intervals of $\approx$ six months that persisted during the rising and peak phases of Solar Cycl…