在D^{+}→K^{-}K^{+}π^{+}衰变中观察到的CP违规的测量
R Aaij1, A S W Abdelmotteleb2, C Abellan Beteta3
1Nikhef National Institute for Subatomic Physics, Amsterdam, Netherlands.
Physical review letters
|January 3, 2025
概括
这项研究使用LHCb数据在D+衰变中寻找电荷平价 (CP) 对称性违反. 没有发现CP违规的证据,为多体衰变设置了新的灵敏度记录.
科学领域:
- 粒子物理学 粒子物理学
- 高能物理 高能物理
- 违反对称性的行为
背景情况:
- 电荷平价对称 (CP) 是粒子物理学的一个基本原理.
- 了解CP违规对于解释宇宙中的物质-反物质不对称至关重要.
- D+→K+π+衰变提供了一个独特的道来探测CP对称性.
研究的目的:
- 在D+→K-K+π+衰变中寻找CP对称性的违反.
- 在这个衰变通道中测量可观测的CP不对称性.
- 在多体衰变中为CP违规设置新的极限.
主要方法:
- 利用了来自13 TeV的LHCb探测器的质子对质子碰撞数据.
- 采用一种新的模型独立技术来比较D+和D-相位空间分布.
- 使用D_s+→K-K+π+控制通道减去仪器不对称.
主要成果:
- 对于 CP 保存假设的 p 值为 8.1%.
- 测量CP不对称的可观测值:A_CP下载S^φπ+ = (0.95±0.43_stat±0.26_syst) ×10^-3和A_CP下载S^K*0K+ = (-0.26±0.56_stat±0.18_syst) ×10^-3.
- 没有发现CP违规的证据.
结论:
- 结果显示,在D+→K-K+π+衰变中没有证据表明CP违规.
- 这代表了迄今为止在多体衰变的相位空间中对CP违规的最敏感的搜索.
- 这些发现有助于对粒子物理学中基本对称性的持续调查.
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