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arXiv · hep-ph/0006043

Improved Unitarized Heavy Baryon Chiral Perturbation Theory for $πN $ Scattering

A. Gómez Nicola·J. Nieves·J. R. Peláez·E. Ruiz Arriola
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Abstract

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 $Δ$ 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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A. Gómez Nicola, J. Nieves, J. R. Peláez, E. Ruiz Arriola. 2000-06-05. Improved Unitarized Heavy Baryon Chiral Perturbation Theory for $πN $ Scattering. https://doi.org/10.1016/s0370-2693(00)00761-9

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