粲偶素及其本质的耦合道分析

Coupled-channel analysis for vector charmonia and their nature

摘要: 我们采用半三体幺正耦合道模型，对BESIII和Belle实验在√s=3.75-4.7 GeV能区获取的高精度e^+e^-\to c\barc 数据（涵盖20种末态组合）进行分析。通过拟合得到的振幅提取出J^\mathrmPC=1^-- 粲偶素极点，除发现粒子数据手册（PDG）收录的已知 \psi 态外，还识别出若干靠近粲介子阈口的态。基于阈口附近极点的构成性分析表明： \psi \left(4040\right) 可能主要包含D^*\barD^*分子态成分，而非传统夸克模型所描述的 \psi \left(3S\right) 态；此外， \psi \left(4230\right) 和 \psi \left(4360\right) 可能是D_1\left(2420\right)\barD，D_1\left(2420\right)\barD^*，D_s^*\barD_s^*与c\barc成分的实质性混合态。

Abstract: High-precision e^+e^-\to c\barc data (20 final states) from the BESIII and Belle at \sqrts=3.75–4.7 GeV are analyzed with a semi three-body unitary coupled-channel model. After fitting the data, we extract J^\mathrmPC=1^-- charmonium poles from the obtained amplitudes. We find well-known \psi states listed in the PDG (particle data group), and also several states near thresholds of open-charm channels. The compositeness analysis suggests that \psi(4040) could mainly consist of a D^*\barD^*—molecule component, rather than a conventionally accepted quark-model \psi(3S) state. Additionally, \psi(4230) and \psi(4360) might be substantial mixtures of D_1(2420)\barD, D_1(2420)\barD^*, D_s^*\barD_s^*, and c\barc components.