%0 Journal Article
%A Gómez Nicola, Ángel
%A Nieves, J.
%A Peláez Sagredo, José Ramón
%A Ruiz Arriola, E.
%T Improved unitarized Heavy Baryon Chiral Perturbation Theory for π N scattering
%D 2000
%@ 0370-2693
%U https://hdl.handle.net/20.500.14352/59585
%X We show how the unitarized description of pion nucleon scattering within Heavy Baryon Chiral Perturbation Theory can be considerably improved, by a suitable reordering of the expansion over the nucleon mass. Within this framework, the ∆ resonance and its associated pole can be recovered from the chiral parameters obtained from low-energy determinations. In addition, we can obtain a good description of the six S and P wave phase shifts in terms of chiral parameters with a natural size and compatible with the Resonance Saturation Hypothesis.
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