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arXiv · 2002.00986

Large-$N_c$ analysis of magnetic and axial two-nucleon currents in pionless effective field theory

Thomas R. Richardson·Matthias R. Schindler
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Abstract

We analyze magnetic and axial two-nucleon contact terms in a combined large-$N_c$ and pionless effective field theory expansion. These terms play important roles in correctly describing, e.g., the low-energy cross section of radiative neutron capture and the deuteron magnetic moment. We show that the large-$N_c$ expansion hints towards a hierarchy between the two leading-order magnetic terms that matches that found in phenomenological fits. We also comment on the issue of naturalness in different Lagrangian bases.

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Thomas R. Richardson, Matthias R. Schindler. 2020-05-25. Large-$N_c$ analysis of magnetic and axial two-nucleon currents in pionless effective field theory. https://doi.org/10.1103/physrevc.101.055505

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