在一个活跃的银河系核NGC 1068喷射中,来自β衰变的中微子和玛射线
Koichiro Yasuda1, Nobuyuki Sakai2, Yoshiyuki Inoue2,3,4
1University of California, Los Angeles, Department of Physics and Astronomy, Los Angeles, California 90095-1547, USA.
Physical review letters
|May 2, 2025
概括
来自星系NGC 1068的高能中微子和玛射线是由中子β衰变解释的. 这种涉及光分解的模型与观测到的马射线缺陷保持一致,可以应用于其他活跃星系.
科学领域:
- 天体物理学 天体物理学
- 粒子天体物理学 粒子天体物理学
- 高能天体物理学 高能天体物理学
背景情况:
- 像NGC 1068这样的活跃星系会发射高能中微子和玛射线.
- 以前的模型经常难以同时解释观察到的流量.
- 质子-光子相互作用是常见的解释,但可能导致对玛射线流量的高估.
研究的目的:
- 提出和验证一个新的模型,解释同时检测TeV中微子和高能马射线的NGC 1068.
- 调查核光分解和随后的β衰变在活跃银河系核喷气中的作用.
- 为了使观察到的中微子和马射线流与理论预测相协调.
主要方法:
- 模拟-4核的光分解,在活跃的银河系核喷气中的紫外线光子.
- 模拟光分解产生的中子的β衰变.
- 从这些过程中计算出预期的中微子和马射线流.
- 将模型预测与NGC 1068的观测数据进行比较.
- 考虑到通过贝特 - 希特勒对生产和光子过程从质子发出同步子和逆康普顿辐射.
主要成果:
- 该模型成功地解释了观察到的TeV中性子能量 (1-100 TeV) 通过从PeV能量的-4光分解中产生的中子β衰变.
- 来自β衰变的预测TeV马射线流量明显低于中微子流量,与NGC 1068中观察到的马射线缺陷一致.
- 结合的场景,包括质子诱导的过程,也可以解释观察到的GeV马射线流对于可信的喷射磁场强度.
- 拟议的机制适用于其他活跃星系,如NGC 4151.
结论:
- 在-4光分解后的中子β衰变为NGC 1068所观测到的TeV中微子和马射线提供了可行的解释.
- 这种模型解决了通常在以质子为基础的模型中遇到的马射线缺陷问题.
- 未来的中性子风味比率测量可以为这种β衰变起源提供关键证据.
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