Latitudinal transport of 7 MeV Jovian and galactic electrons in the inner heliosphere

Abstract

The heliospheric modulation of galactic and Jovian electrons is studied using a fully three-dimensional, steady-state model based on Parker's transport equation including the Jovian source. The model is used to study the latitudinal transport of both 7 MeV Jovian and galactic electrons by illustrating how the electron intensities are affected at different latitudes when enhancing perpendicular diffusion in the polar directions. In particular, the electron intensity-time profile along the Ulysses trajectory is calculated for various assumptions for perpendicular diffusion in the polar directions and compared to the 3-10 MeV electron flux observed by Ulysses from launch up to the end of the first out-of-ecliptic orbit. Comparison of the model computations and the observations give an indication as to the magnitude of this diffusion coefficient. The relative contributions of the Jovian and galactic electrons to the total electron intensity are shown along the Ulysses trajectory.