在PandaX-4T中从大气中搜索轻暗物质
Xuyang Ning, Abdusalam Abdukerim, Zihao Bo
1School of Physics and Technology, Nanjing Normal University, Nanjing 210023, China.
Physical review letters
|August 11, 2023
概括
研究人员使用宇宙射线碰撞寻找来自埃塔中子衰变的轻暗物质. 没有发现过量,这为轻暗物质与原子核的相互作用通过标量介质设定了新的极限.
科学领域:
- 粒子物理学 粒子物理学
- 天体粒子物理学的物理学
- 宇宙学的宇宙学是什么?
背景情况:
- 暗物质仍然是物理学中的一个重要团.
- 宇宙射线与地球大气层的相互作用产生了二次粒子,包括eta (η) 中子.
- 埃塔介子可以分解成暗物质粒子,这些粒子可能与原子核相互作用.
研究的目的:
- 为了寻找由eta中子衰变产生的轻暗物质.
- 开发和应用一种新的模拟增强暗物质的框架.
- 建立光暗物质和原子核之间的相互作用截面的约束.
主要方法:
- 使用PandaX-4T探测器调试数据,年暴露量为0.63.
- 开发了模拟增强暗物质的一般框架,包括地球衰减效应 (弹性和准弹性散射).
- 执行专门的模拟,考虑大气产量和探测器相互作用.
主要成果:
- 没有观察到背景以上信号事件的显著过剩.
- 建立了光暗物质与核相互作用的第一个约束,这种相互作用由光级粒子介导.
- 对于0.1 MeV/c2的暗物质质量和300 MeV/c2的介质质量,在5.9×10−37 cm2的相互作用截面上设置一个较低的排除极限.
- 在eta (η) 到暗物质衰变分支比上限达到1.6×10−7.
结论:
- 搜索没有提供来自eta中子衰变的轻暗物质的证据.
- 这项研究为这种特定的轻暗物质模型提供了迄今为止最严格的约束.
- 开发的模拟框架是公开可访问的,适用于其他增强的暗物质搜索.
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