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Solution of the Bethe-Salpeter equation for pion-nucleon scattering

A. D. Lahiff·I. R. Afnan
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Abstract

A relativistic description of pion-nucleon scattering based on the four-dimensional Bethe-Salpeter equation is presented. The kernel of the equation consists of s- and u-channel nucleon and delta pole diagrams, as well as rho and sigma exchange in the t-channel. The Bethe-Salpeter equation is solved by means of a Wick rotation, and good fits are obtained to the s- and p-wave phase shifts up to 360 MeV pion laboratory energy. The coupling constants determined by the fits are consistent with the commonly accepted values in the literature.

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A. D. Lahiff, I. R. Afnan. 1999-05-27. Solution of the Bethe-Salpeter equation for pion-nucleon scattering. https://doi.org/10.1103/physrevc.60.024608

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