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

在对主要在太阳最低活动期间的内日光层的三维结构进行了十年的非常成功的探索之后，尤利西斯号航天器现在再次向高太阳纬度进发。与之前的最小任务不同，尤利西斯现在开始在它的第二个绕太阳的黄道外轨道上经历太阳最大值条件。这为研究太阳活动高峰期宇宙射线和其他高能粒子的三维传输提供了独特的机会。人们对这一时期各种输送过程的重要性知之甚少，特别是对高度可变的太阳风等离子体中扩散和大尺度梯度和曲率漂移对太阳活动的依赖。由于宇宙飞船独特的轨道和KET仪器的长期数据记录，Ulysses上的基尔电子望远镜(KET)对银河宇宙线和木星电子强度的观测非常适合于研究三维粒子输运。预计至少到2002年，尤利西斯将继续记录一个完整的太阳活动周期。这些数据与模型计算相结合，使用波切夫斯特罗姆大学和波鸿大学开发的复杂的多维数值传输模型，将使我们能够确定各种调制过程的重要性，并限制相关的传输参数(例如扩散系数)。德国和南非小组计划进行的合作将使我们能够改进目前对太阳对银河宇宙线的调制以及木星电子传播的理解。基于双方的实验和建模专业知识，我们期待着成功和富有成效的联合研究合作。

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.