日球鞘内能量氢原子和源质子的能谱的时空特征

项目名称： 日球鞘内能量氢原子和源质子的能谱的时空特征

项目编号： No.41274172

项目类型： 面上项目

立项/批准年度： 2013

项目学科： 天文学、地球科学

项目作者： 王玲华

作者单位： 北京大学

项目金额： 90万元

中文摘要： 日鞘内的高能质子可以和星际介质风中的冷氢原子发生电荷交换转变成为能量氢原子。这些能量氢原子携带着源质子的信息，沿着直线从日鞘向外运动。因此，对日鞘内的能量氢原子和源质子的研究会有力地促进对日球层边界区中的能量转换和粒子加速过程的认识，从而推动日球层边界区动力学的研究。目前，日鞘内粒子研究中尚需解决的重要问题是：日鞘内能量转化的时空特征及其成因是未知的；与能量转化紧密相关的中等能量离子的加速区和机制是不清楚的；起源于这些离子的异常宇宙射线的加速区和机制也是不清楚的。本项目将利用STEREO、IBEX和Cassini飞船的观测，首次建立日球鞘内能量氢原子和源质子从低能到高能的能谱的时空特征的描述，揭示其形成的原因和机制；检验以往的日球层边界区粒子加速理论，探索日鞘内中等能量粒子的加速区和机制；分析日鞘内质子能谱和其时空变化特征与异常宇宙射线的观测的相关性，探索异常宇宙射线的加速区和机制。

中文关键词： 能量中性氢原子；能量转换；粒子加速；；

英文摘要： The energetic ions in the heliosheath can charge exchange with cold hydrogen atoms in the Local Interstellar wind and then become energetic neutral atoms (ENAs). These ENAs will carry the information of their parent ions and leave the heliosheath along a ballistic trajectory. The studies of these ENAs and their parent ions in the heliosheath can greatly help in understanding the energy transport and particle acceleration in the outer boundary of the heliosphere, and thus its dynamics. The important questions that need to be addressed in the study of the heliosheath particles are: how does the energy transport in the heliosheath vary with time and space and what are the causes? Where and how are pickup ions (that are closely related to the energy transport in the heliosheath) accelerated in the heliosheath? Where and how are Anomalous Cosmic Rays (ACRs) (that are believed to originate from the accelerated pickup ions) accelerated in the heliosheath? First, We propose to construct the first temporal and spatial distributions of the energy spectrum of ENAs and their parent ions in the heliosheath, using the ENA measurements from STEREO,IBEX and Cassini, and to investigate the causes that lead to such distributions. Secondly, we will compare observations with the past models of the heliosheath particle acceleration,

英文关键词： Energetic Neutral Atoms；Energy Transport；Particle Acceleration；；