Interplanetary propagation of steady solar injected particles

Abstract

The numerical solution of the spherically symmetric, steady-state Fokker-Planck equation of transport in a system of reference anchored at the Earth with the energy variableT, as measured in a frame moving with the solar wind, shows a good fit to recorded data in interplanetary space during 1965–1968. The boundary condition for a steady-state particle injection at the solar surface considers the energy transformation from the fixed frame into the moving one. Another possible introduction of boundary conditions via the differential current density is also discussed. Densities and gradients in an energy range (≈6 orders of magnitude centred around 1 GeV/nucleon) and radial distances (up to 5 AU) are illustrated in stereographic projections. In our computations the diffusion coefficient is given byKrr=K(r)·K(P), and the densityu reveals itself to be smoothi.e. e=(v/w)|ϖ Inu/ϖ lnT|≪1. wherew is the particle speed andv is the solar-wind velocity. The radial anisotropy in also presented.