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The properties of \bar{K} in the nuclear medium

A. Ramos·E. Oset
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Abstract

The self-energy of the K^- meson in nuclear matter is calculated in a self-consistent microscopic approach, using a \bar{K}N interaction obtained from the lowest-order meson-baryon chiral Lagrangian. The effective \bar{K}N interaction in the medium is derived by solving the coupled-channel Bethe-Salpeter equation including Pauli blocking on the nucleons, mean-field binding potentials for the baryons and the self-energy of the πand \bar{K} mesons. The incorporation of the self-consistent {\bar K} self-energy in the description, in addition to the Pauli blocking effects, yields a weaker attractive in-medium {\bar K}N interaction and a Λ(1405) which dissolves faster with increasing matter density, as a result of the {\bar K} spectral function being spread out over a wide range of energies. These effects are further magnified when the intermediate pions are dressed.

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A. Ramos, E. Oset. 1999-06-07. The properties of \bar{K} in the nuclear medium. https://doi.org/10.1016/s0375-9474(99)00846-5

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