The Lattice QCD Study of the Three-Nucleon Force

TL;DR

This study uses lattice QCD simulations to investigate three-nucleon forces, revealing short-range repulsion in the three-nucleon system, and employs a simplified geometric configuration to manage computational costs.

Contribution

It introduces a method to determine three-nucleon forces from lattice QCD using the NBS wave function, with a focus on the linear three-nucleon configuration.

Findings

Identified short-range repulsive three-nucleon forces.

Utilized a simplified linear configuration to reduce computational cost.

Performed simulations with heavy quark masses at a specific lattice setup.

Abstract

We investigate three-nucleon forces (3NF) from lattice QCD simulations, utilizing the Nambu-Bethe-Salpeter (NBS) wave function to determine two-nucleon forces (2NF) and 3NF on the same footing. Quantum numbers of the three-nucleon (3N) system are chosen to be (I, J^P)=(1/2, 1/2^+) (the triton channel). We consider the simplest geometrical configuration where 3N are aligned linearly with an equal spacing, to reduce the enormous computational cost. Lattice QCD simulations are performed using Nf=2 dynamical clover fermion configurations at the lattice spacing of a = 0.156 fm on a 16^3 x 32 lattice with a large quark mass corresponding to m(\pi) = 1.13 GeV. We find repulsive 3NF at short distance.