The latitudinal transport of energetic particles associated with corotating interaction regions

We investigate the effect of large-scale magnetic turbulence in the solar w ind on the transport of similar to1-10-MeV protons associated with corotati ng interaction regions (CIRs). We develop a quantitative model of the helio spheric magnetic field which is determined by the motions of magnetic foot points near the solar photosphere. The trajectories of many test particles are numerically integrated in this field to examine the variation of the pa rticle distribution function with latitude. The foot points of the magnetic field lines, which extend radially from the source surface, execute a rand om walk in latitude and longitude. We find that the resulting long-waveleng th magnetic fluctuations lead to significant latitudinal field line diffusi on which simultaneously leads to significant latitudinal transport of CIR-a ssociated energetic particles. The results from our model are qualitatively consistent with recent Ulysses observations of recurrent energetic particl e intensity enhancements at high heliographic latitudes.