| Summary Note |
It is common for scientific texts to be organized in logical rather than historical order. Unfortunately, perhaps, nature does not always proceed in that fashion. In an actively evolving field, new ideas and observations build slowly, step by step, often reversing course, and a student should be prepared for this. Therefore, I have included much of the backing and filling and the individual observations which have led to our present understanding.In reading this book, it is important to keep in mind that a realistic understanding must incorporate different kinds of observations. No single inquiry will suffice. Like reading a murder mystery, it is normal to speculate along the way, but we must eventually consider all the evidence, which is not available early in the story. There are many pieces of evidence, of many different kinds, in this mystery. There is now a wealth of evidence on abundances of chemical elements and isotopes and their ionization states and much on electrons; there is onset timing, radio evidence, and the streaming limit; there are injection profiles, intensity dropouts, energy spectral shapes, spectral knees, and particle reservoirs, in addition to the solar associations. All of these help us find the origin, acceleration, distribution, and transport of the solar energetic particles (affectionately SEPs). This has become a rich field. Unlike the murder mystery, however, our hard-won understanding also raises new ques- tions for future scientists to address. The story of SEPs is actually covered in five chapters (cit. from the Preface): |
