用BESIII数据对 χ_{c1}(3872) 线形的合通道分析
M Ablikim1, M N Achasov2, P Adlarson3
1Institute of High Energy Physics, Beijing 100049, People's Republic of China.
Physical review letters
|April 29, 2024
概括
这项研究精确测量了chi_c1(3872) 粒子.
科学领域:
- 粒子物理学 粒子物理学
- 子光谱学 子光谱学
背景情况:
- 奇异子状态的性质仍然是激烈的理论和实验研究的主题.
- 了解它的特性对于推进量子色态动力学 (QCD) 和奇特子模型至关重要.
研究的目的:
- 为了对chi_c1(3872) 线形状进行精确的分析.
- 为了研究合通道和外效应对chi_c1(3872) 反响的影响.
- 为了确定杆结构及其与D*D-bar值的距离.
主要方法:
- 使用了由BESIII探测器收集的e+e- -> gamma chi_c1(3872) 和相关衰变的数据样本.
- 采用了线形参数化,结合了合通道效应和外D*0介质子.
- 分析了不同里曼板上的极点的位置.
主要成果:
- 确定直线形状质量参数M_X为 (3871.63 ± 0.13_{-0.05}^{+0.06}) MeV.
- 在D*0D-bar0分支切割处的第一个和第二个里曼板上确定了两个极点.
- 在第一张纸上设置一个极点显著接近D*0D-bar0值,7.04 ± 0.15_{-0.08}^{+0.07} MeV高于D0D-bar0pi0值,虚构部分为-0.19 ± 0.08_{-0.19}^{+0.14} MeV.
结论:
- 精确的直线形状分析为奇形的性质提供了关键的约束.
- 极点与D*0D-bar0值的距离支持分子解释chi_c1(3872).
- 这项工作有助于更深入地了解粒子物理学中的异国情态.
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