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$ΛΛ$-$ΞN$-$ΣΣ$ coupling in $^{~6}_{ΛΛ}$He with the Nijmegen soft-core potentials

Taiichi Yamada
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Abstract

The $ΛΛ$-$ΞN$-$ΣΣ$ coupling in $^{~6}_{ΛΛ}$He is studied with the [$α$ + $Λ$ + $Λ$] + [$α$ + $Ξ$ + $N$] + [$α$ + $Σ$ + $Σ$] model, where the $α$ particle is assumed as a frozen core. We use the Nijmegen soft-core potentials, NSC97e and NSC97f, for the valence baryon-baryon part, and the phenomenological potentials for the $α-B$ parts ($B$=$N$, $Λ$, $Ξ$ and $Σ$). We find that the calculated $ΔB_{ΛΛ}$ of $^{~6}_{ΛΛ}$He for NSC97e and NSC97f are, respectively, 0.6 and 0.4 MeV in the full coupled-channel calculation, the results of which are about half in comparison with the experimental data, $ΔB^{exp}_{ΛΛ}=1.01\pm0.20^{+0.18}_{-0.11}$ MeV. Characteristics of the $S=-2$ sector in the NSC97 potentials are discussed in detail.

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Taiichi Yamada. 2004-03-03. $ΛΛ$-$ΞN$-$ΣΣ$ coupling in $^{~6}_{ΛΛ}$He with the Nijmegen soft-core potentials. https://doi.org/10.1103/physrevc.69.044301

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