论文标题
中性$ z_c（3900）$和$ z_c（4020）$的辐射衰减
Radiative decays of the neutral $Z_c(3900)$ and $Z_c(4020)$
论文作者
论文摘要
我们研究辐射衰变$ z_c（3900）/z_c（4020）\toγχ_{cj}（γχ_{cj}^\ prime）$（$ j = 0，1，2 $），假设$ z_c（3900）$ z_c（3900）$和$ z_c（4020）$ d $ d^ +c. c. $ d^*{\ bar d}^*$ channel。通过在有效的拉格朗日方法中考虑中间迷人的梅森三角形循环的贡献，这表明，计算出的$ z_c（3900）\ toγχ_{cj} $的部分宽度大约是数百个kevs，而所获得的部分宽度为partial widths $ z_c_c__c（4020）\ to kev tok usev ken ck cj cj cj cj cj cj cj cj { $ z_c（3900）\toγχ_{c0,1}^\ prime $的预测部分宽度小于1 keV，这主要是由于非常小的相位空间。对于$ z_c（4020）\toγχ_{c0,2}^\ prime $，计算出的部分宽度通常小于1 keV。对于$ z_c（4020）\toγχ_{c1}^\ prime $进程，所获得的部分宽度可以达到10 keV的顺序。此外，还研究了不同衰减模式之间这些比率对$ z_c（3900）$或$ z_c（4020）$的质量的依赖性，这对于实验可能是一个很好的数量。希望这里的这些计算可以通过未来的实验来测试。
We study the radiative decays $Z_c(3900)/Z_c(4020) \to γχ_{cJ}(γχ_{cJ}^\prime)$ ($J=0, 1, 2$), with the assumption that the $Z_c(3900)$ and $Z_c(4020)$ couple strongly to $D\bar D^* +c.c$ and $D^*{\bar D}^*$ channel, respectively. By considering the contributions of intermediate charmed mesons triangle loops within an effective Lagrangian approach, it is shown that the calculated partial widths of $Z_c(3900) \to γχ_{cJ}$ are about a few hundreds keVs, while the obtained partial widths $Z_c(4020) \to γχ_{cJ}$ are about tens of keVs. The predicted partial widths of $Z_c(3900)\toγχ_{c0,1}^\prime$ are less than 1 keV, which mainly due to the very small phase space. For $Z_c(4020)\toγχ_{c0,2}^\prime$, the calculated partial widths are usually smaller than 1 keV. For the $Z_c(4020)\toγχ_{c1}^\prime$ process, the obtained partial widths can reach up to the order of 10 keV. Furthermore, the dependence of these ratios between different decay modes on the masses of $Z_c(3900)$ or $Z_c(4020)$ are also investigated, which may be a good quantity for the experiments. It is hoped that these calculations here could be tested by future experiments.
