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arXiv · 1102.1537

\pi N scattering in relativistic baryon chiral perturbation theory revisited

J. M. Alarcon·J. Martin Camalich·J. A. Oller·L. Alvarez-Ruso
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Abstract

We have analyzed pion-nucleon scattering using the manifestly relativistic covariant framework of Infrared Regularization up to {\cal O}(q^3) in the chiral expansion, where q is a generic small momentum. We describe the low-energy phase shifts with a similar quality as previously achieved with Heavy Baryon Chiral Perturbation Theory, \sqrt{s}\lesssim1.14 GeV. New values are provided for the {\cal O}(q^2) and {\cal O}(q^3) low-energy constants, which are compared with previous determinations. This is also the case for the scattering lengths and volumes. Finally, we have unitarized the previous amplitudes and as a result the energy range where data are reproduced increases significantly.

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J. M. Alarcon, J. Martin Camalich, J. A. Oller, L. Alvarez-Ruso. 2011-02-08. \pi N scattering in relativistic baryon chiral perturbation theory revisited. https://doi.org/10.1103/physrevc.83.055205

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