Determination of the pNN Coupling Constant in the VPI/GWU pN?pN Partial-Wave and Dispersion Relation Analysis

Abstract

Our extraction of the pion-nucleon coupling constant from \\pi p elastic\nscattering data is outlined. A partial wave analysis (T_{\\pi} < 2100 MeV) is\nperformed simultaneously with a fixed-t dispersion relation analysis (T_{\\pi} <\n800 MeV). The \\pi NN coupling constant g^2/4\\pi is searched to find the best\nfit. The result 13.73 \\pm 0.01 \\pm 0.07 (first error statistical, second\nsystematic) is found to be insensitive to database changes and Coulomb barrier\ncorrections. This value satisfies important elements of low energy QCD like the\nGoldberger-Treiman discrepancy, the Dashen-Weinstein sum rule, and chiral\nperturbation theory predictions of threshold pion photoproduction.\n