对单个卡比博抑制衰变的观察 D^{0}→b_{1}(1235) ^{-}e^{+}ν_{e}和证据证明 D^{+}→b_{1}(1235) ^{0}e^{+}ν_{e}
M Ablikim1, M N Achasov2, P Adlarson3
1Institute of High Energy Physics, Beijing 100049, People's Republic of China.
Physical review letters
|January 30, 2026
概括
研究人员观察到D质子在轴向向量b1(1235) 质子中的半质子衰变. 该研究为D0和D+衰变提供了新的测量结果,与理论预测一致.
科学领域:
- 粒子物理学 粒子物理学
- 高能物理 高能物理
- 量子色态动力学 量子色态动力学
背景情况:
- 魔力介子的半黑色衰变对于理解弱相互作用至关重要.
- 轴向子子质子b1(1235) 在哈德龙衰变中发挥作用,但它在D质子衰变中的参与需要进一步研究.
研究的目的:
- 为了研究D0和D+质子在轴向向量b1(1235) 质子中的半质子衰变.
- 测量产品的分支分数和这些衰变的部分衰变宽度比.
主要方法:
- 分析e+e-碰撞数据在sqrt(s) =3.773 GeV,集成光度为7.9 fb-1,由BESIII探测器收集.
- 识别和重建D0和D+衰变,涉及b1(1235) -> 欧米pi通道.
- 统计分析以确定显著性,分支分数和衰变宽度比率,考虑系统性不确定性.
主要成果:
- 观察了D0 -> b1(1235)-e+nu_e的衰变,其显著度为5.2西格玛.
- 证据表明衰变D+ -> b1(1235)0 e+ nu_e具有3.1西格玛显著性.
- 测量产品分支分数和部分衰变宽度比率与异回旋不变性预测相一致.
结论:
- 该研究成功地观察并提供了涉及b1(1235) 中子的特定半黑顿D中子衰变的证据.
- 这些结果有助于更好地了解龙结构和魅力领域的弱衰变.
- 与同脊柱不变性的一致性支持这些粒子相互作用的理论模型.
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