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用冰块搜索极高能量的中微子和超高能宇宙射线质子部分的第一个约束
R Abbasi1, M Ackermann2, J Adams3
1Department of Physics, Loyola University Chicago, Chicago, Illinois 60660, USA.
Physical review letters
|August 4, 2025
概括
冰块数据显示没有超高能量中微子超过10 PeV,设置了新的流量极限. 这种非观测不利于超高能宇宙射线 (UHECR) 的仅质子起源,补充其他测量.
科学领域:
- 天体物理学 天体物理学
- 粒子物理学 粒子物理学
- 宇宙射线物理学 宇宙射线物理学
背景情况:
- 超高能宇宙射线 (UHECR) 是神秘的粒子,其能量超过10^18 eV.
- 在天体物理学中,UHECRs的起源和组成仍然是一个重要的难题.
- 中微子是最有能量的天体物理过程的潜在信使.
研究的目的:
- 通过使用来自IceCube中微子天文台的大型数据集,搜索扩散的极高能中微子流.
- 为了限制所有风味的中微子流在10^18 eV左右的能量.
- 通过分析中微子非观测来研究UHECR源的组成.
主要方法:
- 对12.6年的IceCube数据分析中微子事件.
- 设定了10 PeV以上的扩散中微子流的上限.
- 将中微子流量极限与不同UHECR组合和源进化场景的预测进行比较.
主要成果:
- 迄今为止,对于10^18 eV的扩散性所有风味中微子流的最严格的上限是:E^2Φ_ν ≈ 10^-8 GeV cm^-2 s^-1 sr^-1.
- 限制UHECRs的质子分数在70%以下 (在90%CL),以使源进化与恒星形成率相似或强于恒星形成率.
- 在IceCube非观测和KM3NeT中微子候选事件之间发现了2.9西格玛的张力.
结论:
- 在某些宇宙进化假设下,高能中微子的非观测不利于UHECR源的纯质子组成.
- 这一结果为UHECR成分提供了一个独立的约束,可以补充空气淋浴实验.
- 这项研究强调了多信使天文学在解开宇宙奥秘方面的重要性.
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