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在B^{+}→D^{*±}D^{}K^{+}衰变中观察新的或类状态
R Aaij1, A S W Abdelmotteleb2, C Abellan Beteta3
1Nikhef National Institute for Subatomic Physics, Amsterdam, Netherlands.
Physical review letters
|October 11, 2024
概括
研究人员使用LHCb数据研究了B质子衰变,在D*D质谱中观察了四种充或类似充的状态. 其中三种共振结构以前没有被观察到,进步了粒子物理学的理解.
科学领域:
- 高能物理 高能物理
- 粒子物理学 粒子物理学
- 量子色态动力学 量子色态动力学
背景情况:
- 乙子衰变为发现新粒子提供了丰富的环境.
- 了解充和充类状态对于测试量子染色动力学至关重要.
- 以前的研究已经暗示了B-meson衰变景观中的异国情调.
研究的目的:
- 为了研究B+→D*±DK+衰变中的共振结构.
- 为了确定观察到的共振的量子数,特别是C平价.
- 确认或发现新的充或类似充状态和异国情调的共振.
主要方法:
- 分析了来自LHCb实验的质子对质子碰撞数据在7,8和13 TeV.
- 适用于B+→D*+D-K+和B+→D*-D+K+衰变通道的同时振幅.
- 通过对D*±D质谱的C平价分析来确定共振特性.
主要成果:
- 观察了四种或类似的状态分解为D*±D: ηc(3945) (0−+), hc(4000) (1+−), χc1(4010) (1++), 和 hc(4300) (1+−).
- 识别至少三个以前未被观察到的状态.
- 在一个新的生产道中确认T*共振 (T_{c[over ̄]s[over ̄]0}^{*}(2870) ^{0}和T_{c[over ̄]s[over ̄]1}^{*}(2900) ^{0}).
结论:
- 这项研究成功地确定和描述了几种充或类似充的状态,扩大了已知的粒子光谱.
- 确定C parities为理论模型提供了关键信息.
- 在不同的衰变通道中确认T*共振加强了它们在重夸克物理学中的存在和重要性.
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