在大约166 TeV的宇宙射线质子频谱中出现硬化的证据,由GRAPES-3实验观测到
F Varsi1, S Ahmad2, M Chakraborty3
1Indian Institute of Technology Kanpur, Kanpur 208016, India.
Physical review letters
|February 16, 2024
概括
在GRAPES-3实验测量了从50 TeV到1.3 PeV的宇宙射线质子光谱. 结果显示光谱硬化在166 TeV左右,表明光谱不是一个单一的功率规律,直到膝盖能量.
科学领域:
- 宇宙射线物理学 宇宙射线物理学
- 天体物理学 天体物理学
- 粒子物理学的粒子物理学.
背景情况:
- 宇宙射线是来自外太空的高能粒子.
- 了解它们的起源和光谱对天体物理学至关重要.
- 之前的测量在能量范围和精度上有局限性.
研究的目的:
- 以高精度测量宇宙射线质子光谱.
- 为了研究光谱特征,如硬化或软化.
- 为了限制宇宙射线起源和加速的模型.
主要方法:
- 使用了GRAPES-3实验,记录了7.81×10^6的广泛空气淋浴事件.
- 使用闪探测器和望远镜测量了电磁和子元件.
- 分析了子的多重分布,以确定主要成分.
主要成果:
- 介绍了从50 TeV到1.3 PeV的宇宙射线质子光谱.
- 在大约166 TeV时观察到显著的光谱硬化.
- 该光谱从单一的功率定律模型偏离到膝盖能量 (~3 PeV).
结论:
- 宇宙射线质子光谱表现出复杂的行为,不被单一的功率定律描述.
- 观察到的光谱硬化为了解宇宙射线来源提供了关键数据.
- GRAPES-3的结果为高能宇宙射线物理学提供了宝贵的见解.
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