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arXiv · 1903.12275

Theoretical study on \eta'--> 4 pions

Ehsan Jafari·Bing An Li
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Abstract

The $\eta'$ 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 decay of $\eta'\rightarrow \pi^+\pi^-\pi^{+(0)}\pi^{-(0)}$. In this study, the contributions of triangle and box anomalies are calculated. It is shown that the contribution of box diagrams is important in this process. We predict branching ratios of $Br(\eta' \rightarrow \pi^+ \pi^- \pi^+ \pi^-)={1 \over 2}Br(\eta' \rightarrow \pi^+ \pi^- \pi^0 \pi^0) = (8.3 \pm 1.2) \times 10^{-5}$, which is in good agreement with BESIII measurement.

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Ehsan Jafari, Bing An Li. 2019-03-28. Theoretical study on \eta'--> 4 pions. https://doi.org/10.1016/j.nuclphysb.2021.115447

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