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arXiv · 1712.02664

Repulsion and absorption of the $\Sigma$-nucleus potential for $\Sigma^-$-$^5$He in the $^6$Li($\pi^-$, $K^+$) reaction

Toru Harada·Ryotaro Honda·Yoshiharu Hirabayashi
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Abstract

We study phenomenologically inclusive spectra of the $^6$Li($\pi^-$, $K^+$) reaction at 1.2 GeV/$c$ within a distorted-wave impulse approximation with the optimal Fermi-averaging $\pi^- p \to K^+ \Sigma^-$ $t$ matrix. We attempt to clarify the property of a $\Sigma$-nucleus potential for $\Sigma^-$-$^5$He by comparing the calculated spectra with the data of the J-PARC E10 experiment. The result shows that the repulsive and absorptive components of the $\Sigma^-$-$^5$He potential provide the ability to explain the data of the continuum spectra in $\Sigma$ and $\Lambda$ regions; the strengths of $V_\Sigma \simeq$ +30 MeV and $W_\Sigma \simeq$ $-$26 MeV are favored within the Woods-Saxon potential, consistent with analyses for heavier nuclei. Effects of the size and potential range for $\Sigma^-$-$^5$He in the neutron excess of $(N-Z)/(N+Z)=$ 0.2 are also discussed.

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Toru Harada, Ryotaro Honda, Yoshiharu Hirabayashi. 2017-12-07. Repulsion and absorption of the $\Sigma$-nucleus potential for $\Sigma^-$-$^5$He in the $^6$Li($\pi^-$, $K^+$) reaction. https://doi.org/10.1103/physrevc.97.024601

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