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arXiv · 2501.14227

Theoretical study of the $\Sigma N$ cusp in the $K^-d\rightarrow\pi\Lambda N$ reaction

Shunsuke Yasunaga·Daisuke Jido
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Abstract

The $K^-d\rightarrow\pi\Lambda N$ reaction is useful for exploring the hyperon-nucleon interaction through final state interactions. In particular, the cusp structure of the $\Lambda N$ invariant mass spectrum at the $\Sigma N$ threshold contains information about the s-wave interaction of 1/2-isospin hyperon-nucleon systems. The calculation of the spectrum is performed with the aim of extracting the scattering length of the $\Sigma N(I=1/2)$ channel that couples to the $\Lambda N$ channel from this reaction, and the results are discussed in comparison with experimental data to highlight the factors that should be considered.

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Shunsuke Yasunaga, Daisuke Jido. 2025-01-24. Theoretical study of the $\Sigma N$ cusp in the $K^-d\rightarrow\pi\Lambda N$ reaction. https://arxiv.org/abs/2501.14227

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