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Lambda-Lambda bond energy from the Nijmegen potentials

I. Vidana·A. Ramos·A. Polls
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Abstract

The $ΛΛ$ bond energy $ΔB_{ΛΛ}$ in $ΛΛ$ hypernuclei is obtained from a $G$-matrix calculation which includes the coupling between the $ΛΛ$, $ΞN$ and $ΣΣ$ channels, as well as the effect of Pauli blocking to all orders. The Nijmegen NSC97e model is used as bare baryon-baryon interaction in the strangeness $S=-2$ sector. The $ΛΛ$-$ΞN$ coupling increases substantially the bond energy with respect to the uncoupled $ΛΛ$ case. However, the additional incorporation of the $ΣΣ$ channel, which couples simultaneously to $ΛΛ$ and $ΞN$ states, has a surprisingly drastic effect and reduces the bond energy down to a value closer to that obtained in an uncoupled calculation. We find that a complete treatment of Pauli blocking reduces the repulsive effect on the bond energy to about half of what was claimed before.

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I. Vidana, A. Ramos, A. Polls. 2004-07-13. Lambda-Lambda bond energy from the Nijmegen potentials. https://doi.org/10.1103/physrevc.70.024306

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