This grant will fund theoretical studies of the interaction of energetic particles with the solar wind. The studies will be broad-based: they will emphasize shock-accelerated particles and pickup ions but will include galactic cosmic rays, solar flare particles and the cosmic comparisons between theory and observations, and the microprocesses of the interaction including wave excitation by the energetic particles and the quasilinear and nonlinear interaction between the waves and particles. Specific topics of research are, for example: (1) Shock-accelerated ion distributions at energies just above injection. (2) The mechanism which limits diffuse ion energy spectra at Earth's bow shock to exponential in energy per charge, and a search for the effects of curvature and gradient drifts on the spectra. (3) The acceleration of solar flare ions at coronal shocks including shock evolution and ion wave excitation. (4) Wave excitation in the solar wind by interstellar pickup hydrogen including wave coupling between outward and inward propagating waves. (5) Fundamental studies in the quasilinear evolution of pickup ions upstream of comets. (6) Galactic cosmic ray modulation in the outer heliosphere. The overall aim is to use energetic particles as probes of the electromagnetic environment of the earth and the sun.
