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Hyperonic mixing in five-baryon double-strangeness hypernuclei in a two-channel treatment

D. E. Lanskoy·Y. Yamamoto
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Abstract

Properties of hypernuclei $_{ΛΛ}^5$H and $_{ΛΛ}^5$He are studied in a two-channel approach with explicit treatment of coupling of channels ^3\text{Z}+Λ+Λand α+Ξ. Diagonal ΛΛand coupling ΛΛ-ΞN interactions are derived within G-matrix procedure from Nijmegen meson-exchange models. Bond energy ΔB_{ΛΛ} in $_{ΛΛ}^5$He exceeds significantly that in $_{ΛΛ}^5$H due to the channel coupling. Diagonal Ξαattraction amplifies the effect, which is sensitive also to Λ-core interaction. The difference of the ΔB_{ΛΛ} values can be an unambiguous signature of the ΛΛ-ΞN coupling in ΛΛhypernuclei. However, improved knowledge of the hyperon-nucleus potentials is needed for quantitative extraction of the coupling strength from future data on the ΛΛhypernuclear binding energies.

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D. E. Lanskoy, Y. Yamamoto. 2003-11-24. Hyperonic mixing in five-baryon double-strangeness hypernuclei in a two-channel treatment. https://doi.org/10.1103/physrevc.69.014303

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