Pion–Nucleon Scattering in a New Approach to Chiral Perturbation Theory
نویسنده
چکیده
We study pion–nucleon scattering with a chiral lagrangian of pions, nucleons, and ∆-isobars. The scattering amplitude is evaluated to one-loop Q3 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. PACS number(s): 21.30.+y, 21.60.Jz, 21.65.+f Typeset using REVTEX 1
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