HR: 0800h
AN: SH21C-0435    [Abstracts]
TI: Compound and Perpendicular Diffusion of Solar Energetic Particles and Field Line Random Walk
AU: * Webb, G M
EM: gmwebb@citrus.ucr.edu
AF: Institute of Geophysics and Planetary Physics, University of California Riverside, 900 University Ave., Room 1432, Geology Bldg., Riverside, CA 92521 United States
AU: Zank, G P
EM: zank@ucrac1.ucr.edu
AF: Institute of Geophysics and Planetary Physics, University of California Riverside, 900 University Ave., Room 1432, Geology Bldg., Riverside, CA 92521 United States
AU: Kaghashvili, E K
EM: ekaghash@citrus.ucr.edu
AF: Institute of Geophysics and Planetary Physics, University of California Riverside, 900 University Ave., Room 1432, Geology Bldg., Riverside, CA 92521 United States
AU: le Roux, J A
EM: jakobus@ucrac1.ucr.edu
AF: Institute of Geophysics and Planetary Physics, University of California Riverside, 900 University Ave., Room 1432, Geology Bldg., Riverside, CA 92521 United States
AU: Li, G
EM: ganli@citrus.ucr.edu
AF: Institute of Geophysics and Planetary Physics, University of California Riverside, 900 University Ave., Room 1432, Geology Bldg., Riverside, CA 92521 United States
AB: Simulations of energetic charged particle transport in random magnetic fields by Giacalone and Jokipii (1999), Mace et al. (2000) and Qin et al. (2002,2003) demonstrate that the quasilinear theory of diffusion of cosmic rays normal to the magnetic field is somewhat unsatisfactory. A more satisfactory theory for perpendicular diffusion, which better fits the simulations is the nonlinear guiding center theory of Matthaeus et al. (2003); Zank et al. (2004) and Shalchi et al. (2004), but this theory does not account for compound diffusion of particles perpendicular to the field observed in near slab turbulence. In this paper, we use a model for particle transport normal to the random walking mean magnetic field, based on a Chapman Kolmogorov equation, in which the particle is transported relative to the random walking field line. The model indicates that the particle can undergo both compound diffusion and ordinary diffusion perpendicular to the mean magnetic field. If the particle propagates in a ballistic fashion along the field at early times (as described by the telegrapher equation), then the particle diffuses perpendicular to the field at essentially the classical field line random walk (FLRW) value given by Jokipii (1966). We discuss the relation between this model, and the work of Chuvilgin and Ptuskin (1993) on perpendicular and compound diffusion.
DE: 2118 Energetic particles, solar
SC: SPA-Solar and Heliospheric Physics [SH]
MN: 2004 AGU Fall Meeting