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在sqrt[s]=13 TeV的质子对质子碰撞中寻找带微小电荷的粒子
A Hayrapetyan1, A Tumasyan1, W Adam2
1Yerevan Physics Institute, Yerevan, Armenia.
Physical review letters
|April 18, 2025
概括
这项研究在大型强子对撞机 (LHC) 寻找带有微小电荷的粒子,不包括高达640GeV的质量和低至e/3.3的电荷. 这些结果为这种Drell-Yan生产模式设定了最严格的限制.
科学领域:
- 高能物理 高能物理
- 粒子物理学 粒子物理学
- 碰撞器物理学 碰撞器物理学
背景情况:
- 在大型强子对撞机 (LHC) 寻找新的物理现象对于理解基本粒子至关重要.
- 之前的搜索已经探索了各种电荷状态,但低于电子电荷 (e) 的部分电荷粒子在很大程度上仍然不受限制.
- 德雷尔-扬生产机制是产生新粒子在质子-质子碰撞中的关键过程.
研究的目的:
- 在LHC进行首次搜索,寻找具有e/3和0.9e之间的微分电荷的新粒子.
- 为具有2e/3.3电荷的粒子扩展以前的极限.
- 在特定的生产道中为此类颗粒建立最严格的排除限值.
主要方法:
- 利用了在2016年至2018年期间在13 TeV的质量中心能量下收集的138个反向的质子对质子碰撞数据的数据集.
- 采用跟踪探测器中的小能量损失作为主要可观测值来识别部分电荷粒子的潜在信号.
- 分析了来自CERN LHC的数据,重点关注类似Drell-Yan的生产过程.
主要成果:
- 不包括在 95% 的置信度水平下,质量高达 640 GeV 的部分电荷粒子.
- 为粒子带电荷低至e/3.3的粒子设置新的排除极限.
- 确立了迄今为止最严格的Drell-Yan类产生带电量在e/3和0.9e之间的粒子的极限.
结论:
- 搜索成功地限制了LHC中部分电荷粒子的参数空间.
- 结果表明LHC实验对低电荷粒子搜索的敏感性.
- 这项研究显著推进了超越标准模型的物理学探索.
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