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arXiv · hep-ph/9709354

Pion--Nucleon Scattering in a New Approach to Chiral Perturbation Theory

Paul J. Ellis·Hua-Bin Tang
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Abstract

We study pion--nucleon scattering with a chiral lagrangian of pions, nucleons, and $Δ$-isobars. The scattering amplitude is evaluated to one-loop $Q^3$ order, where $Q$ is a generic small momentum, using a new approach which is equivalent to heavy baryon chiral perturbation theory. We obtain a good fit to the experimental phase shifts for pion center-of-mass kinetic energies up to 100 MeV. A sigma term greater than 45 MeV is favored, but the value is not well determined.

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Paul J. Ellis, Hua-Bin Tang. 1998-06-11. Pion--Nucleon Scattering in a New Approach to Chiral Perturbation Theory. https://doi.org/10.1103/physrevc.57.3356

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