Time-dependent transport of energetic charged particles in the dynamical heliosphere

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After a decade of highly successful exploration of the three-dimensional structure of the inner heliosphere mainly during solar minimum activity, the Ulysses spacecraft is now heading towards high heliographic latitudes again. In difference to the previous minimum mission, Ulysses now starts to experience solar maximum conditions in its second out-of-ecliptic orbit around the Sun. This offers the unique opportunity to investigate the three-dimensional transport of cosmic rays and other energetic particles during a solar maximum activity period. Very little is known about the importance of the various transport processes during such periods, in particular about the solar activity dependence of diffusion and large-scale gradient and curvature drifts in the highly variable solar wind plasma. The observations of both galactic cosmic ray and Jovian electron intensities with the Kiel Electron Telescope (KET) onboard Ulysses are ideally suited to study the three-dimensional particle transport because of the spacecraft's unique trajectory and the longterm data recording by the KET instrument. It is expected that Ulysses will continue to record a complete solar activity cycle at least until 2002. These data combined with model calculations, using sophisticated multi-dimensional numerical transport models developed at the Universities of Potchefstroom and Bochum, will allow us to determine the significance of the various modulation processes and constrain the relevant transport parameters (e.g. the diffusion coefficients). The intended collaboration between the German and South African groups will enable us to improve the current understanding of solar modulation of galactic cosmic rays as well as the propagation of Jovian electrons. Based on the experimental and modelling expertise on either side we anticipate a successful and productive joint research collaboration.