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The baryon-decuplet in the chiral dynamics of Lambda-hyperons in nuclear matter

J. Martin Camalich·M. J. Vicente Vacas
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Abstract

We study the long range part of the $Λ$-hyperon optical potential in nuclei using Quantum Many Body techniques and flavor-SU(3) Chiral Lagrangians as starting point. More precisely, we study the contributions to the $Λ$-hyperon optical potential due to the long-range two-pion exchange, with $Σ$ and $Σ^*$ baryons in the internal baryonic lines and considering Nh and $Δ$h excitations. We also consider the contribution to the spin-orbit potentials that comes out from these terms. Our results support a natural explanation of the smallness of the $Λ$-nuclear spin-orbit interaction and shows the importance of the $Σ^*$ and $Δ$ degrees of freedom for the hyperon-nucleus interactions.

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J. Martin Camalich, M. J. Vicente Vacas. 2006-12-01. The baryon-decuplet in the chiral dynamics of Lambda-hyperons in nuclear matter. https://doi.org/10.1103/physrevc.75.035207

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