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arXiv · 1803.09613

Three-nucleon force in chiral EFT with explicit $Δ(1232)$ degrees of freedom: Longest-range contributions at fourth order

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

We analyze the longest-range two-pion exchange contributions to the three-nucleon force at leading-loop order in the framework of heavy-baryon chiral effective field theory with explicit $Δ(1232)$ degrees of freedom. All relevant low-energy constants which appear in the calculation are determined from pion-nucleon scattering. Comparing our results with the ones obtained in the $Δ$-less theory at N4LO, we find effects of the $Δ$ isobar for this particular topology to be rather well represented in terms of resonance saturation of various low-energy constants in the $Δ$-less approach.

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H. Krebs, A. M. Gasparyan, E. Epelbaum. 2018-03-26. Three-nucleon force in chiral EFT with explicit $Δ(1232)$ degrees of freedom: Longest-range contributions at fourth order. https://doi.org/10.1103/physrevc.98.014003

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