K. Holinde

A meson exchange model for the hyperon-nucleon interaction

Abstract A meson exchange model for the hyperon-nucleon (AN, ΣN) interaction is presented, which is constructed along the same guidelines as those applied in the Bonn model for the NN interaction. Numerical results for the scattering data compare favorably with existing empirical information.

Meson-exchange hyperon-nucleon interactions in free scattering and nuclear matter

Abstract Hyperon-nucleon interaction models A and B are presented, in which the explicit energy-dependence of the original models A, B of the Julich group is removed in order to simplify the application in nuclear structure calculations. As a byproduct we find that the SU (3) parameters like F (F + D) ratios, if obtained by a fit to the hyperon-nucleon scattering data, do depend on the specific model used and on approximations applied. While all models provide a reasonable description of the scarce cross-section data, sizeable differences occur in the, so far unmeasured, spin observables, especially between our models and the models of the Nijmegen group. A measurement of such spin observables should easily discriminate between present models and thus shed some light on various aspects of hyperon-nucleon interactions like e.g. the proper choice of parameter constraints. In a conventional first-order Brueckner calculation based on the standard choice of single-panicle potentials, the binding energy BΛ(∞) of a Λ hyperon in nuclear matter was found to be 29.8 MeV (31.1 MeV) for model A (B).

Scalar mesons in ππ and Kπ scattering

Abstract We analyze the s-wave phase shifts derived from ππ and Kπ scattering data with a meson exchange model that includes both s - and t -channel exchange. Correlated ππ, K K , and Kπ pairs play a crucial role in explaining the phase shifts and the elasticity parameter below 1 GeV. Genuine scalar mesons are necessary to fit the s-wave phases in the I =0 ππ channel in the I= 1 2 K π channel for energies beyond 1 GeV.

The Jülich hyperon-nucleon interaction models

AbstractHyperon-nucleon interaction models (A, B), which have been developed in the meson-exchange framework by the Jülich group, are reviewed, with some emphasis on characteristic conceptual differences compared to corresponding interactions constructed by the Nijmegen group. We report on two new versionsà and

Consistent evaluation of charge-symmetry breaking effects in the neutron-proton interaction

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The scalar form factor of the pion, kaon and nucleon

in which the explicit energydependence of the original models A and B is removed in order to simplify application in nuclear structure calculations. As a byproduct of our analysis we find that the resulting SU(3)-parameters likeF/(F+D) ratios do depend on the specific model used an on approximations applied. While all models provide a reasonable description of the scarce cross-section data, sizeable differences occur in the, so far unmeasured, spin observables, especially between our models and the Nijmegen soft-core model NSC. This demonstrates clearly that a measurement of such observables can easily discriminate between present models and thus shed some light on various aspects of the hyperon-nucleon interactions like e.g. the proper choice of parameter constraints. In addition, the results obtained with the energy-independent potentials (Ã,

A meson-exchange model for the antihyperon-hyperon production

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