One-Boson-Exchange Model ofNNandNN¯Interaction

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Abstract
The elastic nucleon-nucleon scattering, due to the exchange of π, η, ρ, ω, ϕ, and an effective I=0 scalar σ meson is calculated using unsubtracted partial-wave dispersion relations with a cutoff. The ρ,ω, and ϕ vector coupling constants are related by SU3 to a single constant assuming pure F coupling. The ratio of the vector to tensor coupling of the ρ meson is determined by the I=1 charge and anomalous magnetic moment ratio and the tensor couplings of ω and ϕ are neglected. The η-nucleon axial-vector coupling constant is related to that of the pion by SU3 with a DF ratio of 32. The I=0 and I=1 phase shifts are calculated using a total of four adjustable parameters: the mass and coupling constant of the effective σ meson, the octet-vector coupling constant, and the cutoff parameter. For each of the cutoff values corresponding to laboratory kinetic energies of 600, 700, and 800 MeV, the remaining three parameters are adjusted to fit the I=1, S01, P03, P13, and P23, and the I=0, S13 phase shifts at 25, 50, 95, 142, 210, and 310 MeV. In each of the three cases, a goodness-of-fit parameter is obtained corresponding to a theory with approximately 10% inherent uncertainty. A deuteron pole appears in the solution for the S13 amplitude corresponding to a binding energy of ∼10 MeV. All of the calculated higher partial-wave phase shifts are in good agreement with results of phase-shift analyses. Having obtained a fit to the nucleon-nucleon phase shifts, the nucleon-antinucleon scattering amplitudes are calculated after changing the signs of the odd G-parity exchange terms (π, ω, and