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Meson-exchange $πN$ Models in Three-Dimensional Bethe-Salpeter Formulation

Cheng-Tsung Hung·Shin Nan Yang·T. -S. H. Lee
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Abstract

The pion-nucleon scattering is investigated by using several three-dimensional reduction schemes of the Bethe-Salpeter equation for a model Lagrangian involving $π$, $N$, $Δ$, $ρ$, and $σ$ fields. It is found that all of the resulting meson-exchange models can give similar good descriptions of the $πN$ scattering data up to 400 MeV. However they have significant differences in describing the $πNN$ and $πNΔ$ form factors and the $πN$ off-shell t-matrix elements. We point out that these differences can be best distinguished by investigating the near threshold pion production from nucleon-nucleon collisions and pion photoproduction on the nucleon. The consequences of using these models to investigate various pion-nucleus reactions are also discussed.

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Cheng-Tsung Hung, Shin Nan Yang, T. -S. H. Lee. 2001-01-28. Meson-exchange $πN$ Models in Three-Dimensional Bethe-Salpeter Formulation. https://doi.org/10.1103/physrevc.64.034309

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