The properties of K̄ in the nuclear medium Original Research Article

The self-energy of the K− meson in nuclear matter is calculated in a self-consistent microscopic approach, using a View the MathML source interaction obtained from the lowest-order meson–baryon chiral Lagrangian. The effective View the MathML source 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 π and K̄ mesons. The incorporation of the self-consistent K̄ self-energy in the description, in addition to the Pauli blocking effects, yields a weaker attractive in-medium View the MathML source interaction and a Λ(1405) which dissolves faster with increasing matter density, as a result of the K̄ spectral function being spread out over a wide range of energies. These effects are further magnified when the intermediate pions are dressed.