The k - meson nucleon interaction & the hadron – nucleus interaction

Abstract

In the first part two inelastic two-body channels of the KN system are examined in energy-dependent partial wave analyses in which each non-resonant partial amplitude is expanded in an orthogonal series of polynomials over a normalised energy-dependent variable. The resonances known to be present in these channels are investigated as well as any possible new resonant states. It is found that the existing resonances are generally adequate to describe the available date for the two channels and that for K¯p → ^π in particular, the present fits form a statistically good solution with little new structure other than in the background phases. In the second part two particular examples of hadron-nucleuselastic scattering are studied using Glaubers multiple-scattering series. The first of these is the scattering of negative pi-mesonsfrom Helium-4, which is studied in detail at medium and high energy. A complete spin and isospin dependent set of πN amplitudes are used together with a number of forms for the nuclear densities. It is found that the use of more elaborate forms docs not provide any significantly better description than the more simple forms available and it is concluded that more realistic nuclear densities may be needed to describe the wide-angle data adequately. The second case studied is the scattering of medium-energy protonsfrom Carbon-12 and a modified form of Glauber series is used with the nucleus described as a state formed from three alpha-particles. Different forms of distribution for these are examined but are generally found to give little improvement over the simple harmonic oscillator densities. An improved a-particle density is proposed which may combine the best properties of the different forms used while retaining simplicity of calculation.