HR: 10:20h
AN: SH42A-01    [Abstracts]
TI: Energy Spectra and Anisotropies at a 2-D Shock: Implications for Voyager-1 and the Termination Shock
AU: * Kota, J
EM: kota@lpl.arizona.edu
AF: University of Arizona, University of Arizona, Lunar and Planetary Laboratory, Tucson, AZ 85721-0092 United States
AU: Jokipii, J R
EM: jokipii@lpl.arizona.edu
AF: University of Arizona, University of Arizona, Lunar and Planetary Laboratory, Tucson, AZ 85721-0092 United States
AU: Giacalone, J
EM: giacalon@lpl.arizona.edu
AF: University of Arizona, University of Arizona, Lunar and Planetary Laboratory, Tucson, AZ 85721-0092 United States
AB: The enhancement of low-energy particle fluxes and large field-aligned anistropies detected by Voyager-1 indicate, most likely, the proximity of the termination shock. It is still debated if Voyager-1 crossed the shock or remained still upstream in the supersonic wind. It seems quite conceivable that Voyager-1 was still inside the shock, but its magnetic field line had already intersected the shock. This may occur naturally if the magnetic field line intersects the shock multiple times, which can occur in a number of plausible ways. We study the effects of such multiple intersection in the framework of diffusive acceleration. We consider a 2-dimensional, quasi-perpendicular planar shock, allowing the direction of the magnetic field to vary along the shock. Energy spectra and anisotropies are calculated by both analytical approximation and numerical solution of Parker's diffusive transport equation in 2-D. The predicted fluxes show quite remarkable spatial variation depending on the configuration of the magnetic field. Energy spectra and anisotropies exhibit cosiderable variability as well. We will discuss the implications for the Voyager-1 observations.
DE: 7524 Magnetic fields
DE: 7851 Shock waves
DE: 2104 Cosmic rays
DE: 2114 Energetic particles, heliospheric (7514)
SC: SPA-Solar and Heliospheric Physics [SH]
MN: 2004 AGU Fall Meeting