Acceleration and propagation of energetic charged particles in the inner heliosphere

Abstract

Both particle propagation and acceleration are intimately related to the strength of scattering. I shall review some recent developments in our understanding of interplanetary propagation, in particular the dawn of a solution of the well-known discrepancy problem between mean free paths (mfp) derived from quasi-linear theory (QLT) and from fits to observational data. With this much improved understanding of particle scattering we can re-evaluate our understanding of particle acceleration at interplanetary shocks. Special attention is paid to the model of coupled hydrodynamic wave excitation and ion acceleration at shocks.