Possible $Σ^*(1/2^-)$ in the initial-state polarized $γN\rightarrow K^{+} Σ^*(1385) \rightarrow K^{+} πΛ$ reaction near threshold

Yun-Hua Chen; Bing-Song Zou

doi:10.1103/physrevc.88.024304

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arXiv · 1302.5466

Possible $Σ^(1/2^-)$ in the initial-state polarized $γN\rightarrow K^{+} Σ^(1385) \rightarrow K^{+} πΛ$ reaction near threshold

Yun-Hua Chen·Bing-Song Zou

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Abstract

By using an effective Lagrangian method, we study the effects of a newly proposed $Σ^*(1/2^-)$ state with mass around 1380 MeV in the initial-state polarized $γN\rightarrow K^{+} Σ^*(1385) \rightarrow K^{+} πΛ$ process near threshold. The theoretical predictions for the helicity cross sections $σ_{3/2}$, $σ_{1/2}$ as well as their ratios, and the angular distributions of $π$ in the $πΛ$ center-of-mass system are given. It is found that assuming $Σ^*(1/2^-)$ exists or not, these physical quantities are distinctly different. So our results could be useful for the investigation of the existence of $Σ^*(1/2^-)$ when the experimental data are available in the future.

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Yun-Hua Chen, Bing-Song Zou. 2013-08-13. Possible $Σ^*(1/2^-)$ in the initial-state polarized $γN\rightarrow K^{+} Σ^*(1385) \rightarrow K^{+} πΛ$ reaction near threshold. https://doi.org/10.1103/physrevc.88.024304

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