较快的太阳能粒子的延迟到来作为对冲击加速过程的探测器
Yuncong Li1,2, Jingnan Guo1,3, Daniel Pacheco1
1National Key Laboratory of Deep Space Exploration/School of Earth and Space Sciences, University of Science and Technology of China, Hefei 230026, China.
National science review
|October 3, 2025
概括
太阳能质子 (SEP) 事件挑战了传统的速度分散. 新的观测揭示了反向速度分散 (IVD),其中更高能量的粒子迟到,这表明了冲击加速机制.
科学领域:
- 空间等离子体物理学 空间等离子体物理学
- 太阳物理 太阳物理
- 天体物理学 天体物理学
背景情况:
- 在太阳爆发期间的粒子加速和运输是空间等离子体物理学的关键问题.
- 传统上,更高能量的粒子更早到达 (速度分散),这是太阳能质子 (SEP) 事件中常见的观察.
- 帕克太阳探测器和太阳轨道探测器最近的观测显示了反向速度分散 (IVD),挑战了这种既定的模型.
研究的目的:
- 报告和分析最近在10个太阳能质子事件中对IVD结构的观察.
- 为了调查导致不寻常的IVD现象的潜在物理机制.
- 确定冲击加速过程的物理条件和时间尺度.
主要方法:
- 欧空局太阳轨道器观测到的10个太阳能质子事件的分析.
- 研究粒子速度分散和逆速度分散现象.
- 模拟与磁再连接相关的冲击扩散加速.
主要成果:
- 在10个太阳能质子事件中证实了反向速度分散 (IVD) 的观测.
- 确定了相对于磁再连接的冲击扩散加速,作为加速质子的潜在主导机制.
- 不能直接观察到的冲击加速过程的确定的物理条件和时间尺度.
结论:
- 这项研究提供了令人信服的证据,证明了太阳能质子事件中的反向速度分散.
- 冲击扩散加速,加上磁再连接,被认为是这些事件中高能粒子加速的主导机制.
- 这项研究为太阳爆发期间冲击加速的条件和时间尺度提供了新的见解.
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