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在sqrt[s]=13 TeV的质子对撞过程中寻找具有非普遍合的中性测量玻色子
A Hayrapetyan1, A Tumasyan1, W Adam2
1Yerevan Physics Institute, Yerevan, Armenia.
Physical review letters
|August 27, 2025
概括
物理学家使用大型强子对撞机的数据寻找新的重中性测量玻色子 (Z'). 没有发现证据, 限制其潜在的质量和衰变特性.
科学领域:
- 高能物理
- 粒子物理学
- 超越标准模型物理
背景情况:
- 粒子物理学的标准模型描述了基本的粒子和力.
- 新重量玻色子的存在,如Z'玻色子,是由标准模型的一些扩展所预测的.
- 寻找新的粒子对于理解宇宙的基本结构至关重要.
研究的目的:
- 进行首次寻找具有非通用费米子合的重中性旋转-1测量玻色子 (Z oun).
- 通过矢量玻色子聚变过程研究Z'玻色子的产生.
- 限制一个潜在的Z'玻色子分解为陶或W玻色子.
主要方法:
- 通过CMS实验收集的大型强子对撞机 (LHC) 数据的分析.
- 使用质量中心能量为13TeV的质子碰撞数据.
- 从2016年到2018年,采用138 fb^{-1}的整合亮度.
- 设定Z'玻色子产生和衰变的横截面和分支分量的上限.
主要成果:
- 收集的数据与标准模型的预测一致.
- 上限设定了生产横截面乘以分支数的Z'小数目.
- 对于2.45TeV的质量,Z'玻色子分解为陶的存在被排除在外.
- 一个Z'玻色子分解为W玻色子的存在被排除在1.60TeV以下的质量.
结论:
- 这项研究首次通过矢量玻色子聚变产生重中性Z'玻色子.
- 在分析的数据集中没有发现Z'玻色子的证据.
- 对一个潜在的Z'玻色子的质量和合有严格的限制,进一步限制了超越标准模型的理论.
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