伽马谱线轮廓研究及在耀斑伽马射线观测的应用

The solar gamma-rays are the most direct and almost unique diagnostic tools for studying the acceleration and transportation of energetic particles (especially for protons and heavy ions) in solar flares. However, due to the complexity of solar gamma-rays calculation and the difficulty of observation analysis, the study of flare-accelerated ions was still a tough subject. On the basis of our previous work about theoretical calculations of solar gamma-ray production and RHESSI satellite observations data analysis, this project will further explore the features of the gamma line shapes, which reveal the characteristic of energetic particle in solar flares. The project will calculate the formation and distribution of gamma-ray lines by Monte-Carlo simulation, and investigate the relationship of line shapes/yields and the flare characteristics, such as the information of accelerated ions and physical condition of interaction region. A set of criteria for analyzing gamma-ray observation data would be established, in order to acquire or limit the properties of flare-accelerated ions efficiently. It will also help to understand the particle acceleration mechanism in flares.

伽马射线是研究太阳耀斑高能粒子（尤其是质子和重核离子）加速和传播最为直接和几乎唯一的手段。但由于耀斑伽马射线理论计算的复杂和分析观测上的困难，耀斑加速离子的研究至今仍是难题。本项目在我们前期工作关于耀斑伽马射线能谱的理论计算和RHESSI卫星伽马射线数据的观测分析基础上，进一步探究伽马谱线轮廓的特征，从而揭示耀斑高能粒子特性。本项目拟通过蒙特卡洛模拟方法，计算谱线的形成和分布，并探讨谱线轮廓、谱线产额与耀斑加速离子和作用区物理特性的变化关系，从而建立起一套有效的判断标准，使之应用于耀斑伽马射线观测分析中，以期有效地获取或限制耀斑加速离子信息，进而有助于认识耀斑中粒子加速机制。