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arXiv · 2010.09420

Hidden spin-isospin exchange symmetry

Dean Lee·Scott Bogner·B. Alex Brown·Serdar Elhatisari·Evgeny Epelbaum·Heiko Hergert·Morten Hjorth-Jensen·Hermann Krebs·Ning Li·Bing-Nan Lu·Ulf-G. Meißner
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Abstract

The strong interactions among nucleons have an approximate spin-isospin exchange symmetry that arises from the properties of quantum chromodynamics in the limit of many colors, $N_c$. However this large-$N_c$ symmetry is well hidden and reveals itself only when averaging over intrinsic spin orientations. Furthermore, the symmetry is obscured unless the momentum resolution scale is close to an optimal scale that we call $\Lambda_{{\rm large-}N_c}$. We show that the large-$N_c$ derivation requires a momentum resolution scale of $\Lambda_{{\rm large-}N_c} \sim 500$ MeV. We derive a set of spin-isospin exchange sum rules and discuss implications for the spectrum of $^{30}$P and applications to nuclear forces, nuclear structure calculations, and three-nucleon interactions.

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Dean Lee, Scott Bogner, B. Alex Brown, Serdar Elhatisari, Evgeny Epelbaum, Heiko Hergert, Morten Hjorth-Jensen, Hermann Krebs, Ning Li, Bing-Nan Lu, Ulf-G. Meißner. 2020-10-19. Hidden spin-isospin exchange symmetry. https://doi.org/10.1103/physrevlett.127.062501

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