Eur. Phys. J. A (2016) 52: 296
https://doi.org/10.1140/epja/i2016-16296-5

Regular Article - Theoretical Physics

Two-nucleon scattering in a modified Weinberg approach with a symmetry-preserving regularization

¹ Institut für Theoretische Physik II, Ruhr-Universität Bochum, D-44780, Bochum, Germany
² Institute for Advanced Simulation, Institut für Kernphysik and Jülich Center for Hadron Physics, Forschungszentrum Jülich, D-52425, Jülich, Germany
³ Tbilisi State University, 0186, Tbilisi, Georgia
⁴ Helmholtz Institut für Strahlen- und Kernphysik and Bethe Center for Theoretical Physics, Universität Bonn, D-53115, Bonn, Germany
⁵ JARA - Forces and Matter Experiments, Forschungszentrum Jülich, D-52425, Jülich, Germany
⁶ JARA - High Performance Computing, Forschungszentrum Jülich, D-52425, Jülich, Germany

^* e-mail: jgegelia@hotmail.com

Received: 9 June 2016
Accepted: 22 August 2016
Published online: 27 September 2016

Abstract

We consider the nucleon-nucleon scattering problem by applying time-ordered perturbation theory to the Lorentz-invariant formulation of baryon chiral perturbation theory. We employ a higher-derivative symmetry-preserving regularization to obtain an integral equation for the scattering amplitude, which permits a non-perturbative treatment of subleading contributions to the nucleon-nucleon potential. The resulting formulation is used to quantify finite regulator artefacts in two-nucleon phase shifts as well as in the chiral extrapolations of the S-wave scattering lengths and the deuteron binding energy. Our approach can be straightforwardly extended to analyse few-nucleon systems and processes involving external electroweak sources.