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arXiv · hep-ph/9609459

Pion-Nucleon Scattering at Low Energies

Paul J. Ellis·Hua-Bin Tang
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Abstract

We study pion-nucleon scattering at tree level with a chiral lagrangian of pions, nucleons, and $Δ$-isobars using a K-matrix unitarization procedure. Evaluating the scattering amplitude to order $Q^2$, where $Q$ is a generic small momentum scale, we obtain a good fit to the experimental phase shifts for pion center-of-mass kinetic energies up to $50 $MeV. The fit can be extended to 150 MeV when we include the order-$Q^3$ contributions. Our results are independent of the off-shell $Δ$ parameter.

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Paul J. Ellis, Hua-Bin Tang. 1997-09-23. Pion-Nucleon Scattering at Low Energies. https://doi.org/10.1103/physrevc.56.3363

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