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Brueckner Rearrangement Effects in $^5_Λ$He and $^6_{ΛΛ}$He

M. Kohno·Y. Fujiwara·Y. Akaishi
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Abstract

Rearrangement effects in light hypernuclei are investigated in the framework of the Brueckner theory. We can estimate without detailed numerical calculations that the energy of the $α$-core is reduced by more than 2.5 MeV when the $Λ$ adheres to $^4$He to form $^5_Λ$He. Similar assessment of rearrangement contributions is essential to deduce the strength of $ΛΛ$ interaction from experimentally observed $ΔB_{ΛΛ}$. The recently observed experimental value of $\sim$ 1 MeV for the $ΔB_{ΛΛ}$ of \hll suggests that the matrix element of $<ΛΛ|v|ΛΛ>$ in \hll is around -2 MeV.

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M. Kohno, Y. Fujiwara, Y. Akaishi. 2003-07-28. Brueckner Rearrangement Effects in $^5_Λ$He and $^6_{ΛΛ}$He. https://doi.org/10.1103/physrevc.68.034302

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