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The piNN vertex function in a meson-theoretical model

R. Boeckmann·C. Hanhart·O. Krehl·S. Krewald·J. Speth
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Abstract

The piNN vertex function is calculated within a dispersion theoretical approach, including both pi-rho and pi-sigma intermediate states, where the sigma meson is an abbreviation for a correlated pion pair in a relative S-wave with isospin I=0. A strong coupling between the pi-sigma and the pi-rho states is found. This leads to a softening of the piNN form factor. In a monopole parameterization, a cut-off Lambda=800 MeV is obtained as compared to Lambda=1000 MeV using pi-rho intermediate states only.

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R. Boeckmann, C. Hanhart, O. Krehl, S. Krewald, J. Speth. 1999-08-10. The piNN vertex function in a meson-theoretical model. https://doi.org/10.1103/physrevc.60.055212

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