The ${\eta }^{\prime }$ meson is associated with the U(1) anomaly. In this paper, a successful effective chiral theory of mesons has been applied to study the anomalous decays of ${\eta }^{\prime }\to {\pi }^{+}{\pi }^{-}{\pi }^{+(0)}{\pi }^{-(0)}$. Contribution of triangle and box diagrams is calculated, which indicates that the box anomaly has a significant contribution to the decay amplitudes. We predict branching ratios of $Br({\eta }^{\prime }\to {\pi }^{+}{\pi }^{-}{\pi }^{+}{\pi }^{-})=\frac{1}{2}Br({\eta }^{\prime }\to {\pi }^{+}{\pi }^{-}{\pi }^0{\pi }^0)=(8.3\pm 1.2)\times {10}^{-5}$, which is in good agreement with BESIII measurement.

中文翻译：

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η '→  π ⁺ π ^- π ^+（0）π- ^（0）的理论研究

这 ${\eta }^{\prime }$介子与U（1）异常相关。在本文中，成功的有效介子手性理论已被应用于研究介子的异常衰变。${\eta }^{\prime }\to {\pi }^{+}{\pi }^{-}{\pi }^{+（0）}{\pi }^{-（0）}$。计算出三角图和箱形图的贡献，这表明箱形异常对衰减幅度有重大贡献。我们预测$乙\mathrm{[R}（{\eta }^{\prime }\to {\pi }^{+}{\pi }^{-}{\pi }^{+}{\pi }^{-}）=\frac{\mathrm{1个}}{\mathrm{2个}}乙\mathrm{[R}（{\eta }^{\prime }\to {\pi }^{+}{\pi }^{-}{\pi }^0{\pi }^0）=（8.3\pm 1.2）\times {10}^{-5}$，与BESIII测量非常吻合。