The basics of focused transport as applied to solar energetic particles are reviewed, paying special attention to areas of common misconception. The micro-physics of charged particles interacting with slab turbulence are investigated to illustrate the concept of pitch-angle scattering, where after the distribution function and focused transport equation are introduced as theoretical tools to describe the transport processes and it is discussed how observable quantities can be calculated from the distribution function. In particular, two approximations, the diffusion-advection and the telegraph equation, are compared in simplified situations to the full solution of the focused transport equation describing particle motion along a magnetic field line. It is shown that these approximations are insufficient to capture the complexity of the physical processes involved. To overcome such limitations, a finite-difference model, which is open for use by the public, is introduced to solve the focused transport equation. The use of the model is briefly discussed and it is shown how the model can be applied to reproduce an observed solar energetic electron event, providing insights into the acceleration and transport processes involved. Past work and literature on the application of these concepts are also reviewed, starting with the most basic models and building up to more complex models.

中文翻译：

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聚焦太阳能粒子传输入门

回顾了应用于太阳高能粒子的聚焦传输的基础知识，特别注意了常见的误解领域。研究了带电粒子与平板湍流相互作用的微观物理学，以说明俯仰角散射的概念，其中引入分布函数和聚焦输运方程作为描述输运过程的理论工具，并讨论了可观察量如何由分布函数计算。特别是，扩散平流和电报方程这两个近似在简化情况下与描述粒子沿磁场线运动的聚焦输运方程的完整解进行了比较。结果表明，这些近似值不足以捕捉所涉及物理过程的复杂性。为了克服这些限制，引入了一个对公众开放的有限差分模型来求解聚焦传输方程。简要讨论了该模型的使用，并展示了如何应用该模型来重现观察到的太阳能高能电子事件，从而深入了解所涉及的加速和传输过程。还回顾了过去关于应用这些概念的工作和文献，从最基本的模型开始，到构建更复杂的模型。简要讨论了该模型的使用，并展示了如何应用该模型来重现观察到的太阳能高能电子事件，从而深入了解所涉及的加速和传输过程。还回顾了过去关于应用这些概念的工作和文献，从最基本的模型开始，到构建更复杂的模型。简要讨论了该模型的使用，并展示了如何应用该模型来重现观察到的太阳能高能电子事件，从而深入了解所涉及的加速和传输过程。还回顾了过去关于应用这些概念的工作和文献，从最基本的模型开始，到构建更复杂的模型。