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arXiv · 1411.3114

A study of hyperons in nuclear matter based on chiral effective field theory

J. Haidenbauer·Ulf-G. Meißner
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Abstract

The in-medium properties of a hyperon-nucleon potential, derived within chiral effective field theory and fitted to Lambda-N and Sigma-N scattering data, are investigated. Results for the single-particle potentials of the Lambda and Sigma hyperons in nuclear matter are reported, based on a conventional first-order Brueckner calculation. The Sigma-nucleus potential is found to be repulsive, in agreement with phenomenological information. A weak Lambda-nucleus spin-orbit interaction can be achieved by an appropriate adjustment of a low-energy constant corresponding to an antisymmetric Lambda-N -- Sigma-N spin-orbit interaction that arises at next-to-leading order in the effective field theory approach.

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J. Haidenbauer, Ulf-G. Meißner. 2015-01-30. A study of hyperons in nuclear matter based on chiral effective field theory. https://doi.org/10.1016/j.nuclphysa.2015.01.005

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