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在NA62寻找暗光子在NA62的勒普顿衰变
E Cortina Gil1, J Jerhot1, A Kleimenova1
1Université Catholique de Louvain, Louvain-La-Neuve, Belgium.
Physical review letters
|September 27, 2024
概括
NA62实验寻找暗光子分解成电子-正电子对,但没有发现任何信号. 这次搜索排除了暗光子参数空间的区域,改善了50-600 MeV/c2.2之间质量的现有限制.
科学领域:
- 粒子物理学 粒子物理学
- 暗物质的搜索 暗物质的搜索
- 高能物理 高能物理
背景情况:
- 暗光子的存在被假设为可见和暗领域之间的中间体.
- 以前的搜索已经限制了暗光子的特性,但在MeV/c2质量范围内仍然存在差距.
研究的目的:
- 用NA62实验的数据搜索暗光子分解成电子-正电子对的证据.
- 为了限制暗光子的参数空间,特别是它们的质量和合强度.
- 将结果解释在与轴子类粒子搜索的背景下.
主要方法:
- 利用CERN的NA62实验在光束倾倒模式下,在2021年收集1.4×1017个质子在倾倒中.
- 分析了暗光子在飞行中的衰变成电子-正子对的数据.
- 结合了与以前在勒普顿-反勒普顿最终状态中寻找暗光子的搜索结果.
主要成果:
- 没有观察到暗光子信号的显著证据.
- 在90%的置信级别下,暗光子参数空间的一个区域被排除在外.
- 改善了50至600 MeV/c2之间的暗光子质量和从10−6到4×10−5.5的合值的实验极限.
结论:
- 该搜索为暗光子特性设定了新的极限,特别是在指定的质量和合范围.
- 这些结果有助于持续的努力,以检测或排除黑暗部门的候选人.
- 该分析还提供了对axionlike粒子模型的约束.
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