在一个补偿的铁磁磁体中,通过中子旋转旋转测量,对奇异的中子-旋转-电子-旋转相互作用的新上限
T Mulkey1, K N Lopez2, C D Hughes2
1Georgia State University, Atlanta, Georgia 30303, USA.
Physical review letters
|March 6, 2026
概括
研究人员通过寻找中子和电子之间的异国情调旋转相互作用来寻找超越标准模型的新物理学. 实验没有发现这些相互作用的证据,改善了新的物理理论的限制.
科学领域:
- 实验性的粒子物理学.
- 中子散射是一种中子散射.
- 超越标准模型的物理学
背景情况:
- 粒子物理学的标准模型描述了基本粒子和力,但并没有解释所有观察到的现象.
- 奇特的旋转-旋转相互作用可能表明新的基本力或粒子.
- 中子极度测量为这种相互作用提供了一个敏感的探测器.
研究的目的:
- 为了寻找中子和电子之间的异国情调的旋转-旋转相互作用.
- 为了限制超越标准模型的新物理模型的参数.
- 为了建立新的合常数积的上限gAe gAn.
主要方法:
- 通过极化电子的密集介质利用缓慢中子极化成像.
- 在其磁性补偿温度下使用铁磁性目标,以创建具有零净磁化的极化电子组合.
- 测量了中子自旋旋转角度作为相互作用长度的函数.
主要成果:
- 每个单位长度的测量平均中子旋转旋转角度为 (dφ ̄F5/dz) =[0.41±6.3(stat) ±4.4(sys) ]×10−3 rad/m.
- 这个结果与零一致,表明没有观察到异国情调的旋转-旋转相互作用.
- 改进了以前的合常数 gAe gAn 的上限数量数量级.
结论:
- 寻找异国情调的中子-电子旋转-旋转相互作用的结果为零.
- 该实验为10−8m和10−2m之间的相互作用范围λc设定了轴联定数gAe gAn的轴联定数积的新严格极限.
- 这项工作有助于限制标准模型之外的新物理学理论.
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