Subleading D-like Three-Nucleon Interactions

TL;DR

This paper analyzes subleading three-nucleon interactions in chiral effective field theory, focusing on D-like forces involving pion exchange and contact terms, and proposes a simplified model based on the Δ(1232) excitation mechanism.

Contribution

It identifies the dependence of D-like three-nucleon forces on 16 low-energy constants and introduces a simplified approximation using 4 constants linked to Δ(1232) excitation.

Findings

The three-nucleon potential depends on 16 low-energy constants.

A simplified model with 4 constants approximates the full interaction.

The Δ(1232) excitation mechanism guides the parameter reduction.

Abstract

We consider subleading contributions to the three-nucleon force from tree-level diagrams involving a single-pion exchange and a contact interaction between two nucleons, which appear at fifth order in the chiral expansion. We show that the corresponding D-like three-nucleon potential depends on 16 low-energy constants, which need to be determined from few-body data. Assuming that their numerical values are governed by the intermediate {\Delta}(1232) excitation mechanism, the considered three-nucleon force can be approximated using 4 low-energy constants that parametrize the short-range nucleon-nucleon to nucleon-{\Delta} transition amplitude.