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arXiv · 1411.3612

Three-nucleon force at large distances: Insights from chiral effective field theory and the large-N_c expansion

E. Epelbaum·A. M. Gasparyan·H. Krebs·C. Schat
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Abstract

We confirm the claim of Ref. [D.R. Phillips, C. Schat, Phys. Rev. C88 (2013) 3, 034002] that 20 operators are sufficient to represent the most general local isospin-invariant three-nucleon force and derive explicit relations between the two sets of operators suggested in Refs. [D.R. Phillips, C. Schat, Phys. Rev. C88 (2013) 3, 034002] and [H. Krebs, A.M. Gasparyan, E. Epelbaum, Phys.Rev. C87 (2013) 5, 054007]. We use the set of 20 operators to discuss the chiral expansion of the long- and intermediate-range parts of the three-nucleon force up to next-to-next-to-next-to-next-to-leading order in the standard formulation without explicit Delta(1232) degrees of freedom. We also address implications of the large-N_c expansion in QCD for the size of the various three-nucleon force contributions.

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E. Epelbaum, A. M. Gasparyan, H. Krebs, C. Schat. 2014-11-13. Three-nucleon force at large distances: Insights from chiral effective field theory and the large-N_c expansion. https://doi.org/10.1140/epja%2Fi2015-15026-y

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