Momentum space evolution of chiral three-nucleon forces

TL;DR

This paper introduces a framework for evolving chiral three-nucleon forces in momentum space using SRG, demonstrating unitarity, decoupling, and universality, enabling consistent combination with two-nucleon interactions for nuclear calculations.

Contribution

It presents the first momentum-space evolution method for chiral 3N forces using SRG, ensuring unitarity and consistency with 2N interactions.

Findings

SRG transformation is unitary and preserves physics.

Low and high momenta are effectively decoupled.

Chiral 3N forces exhibit universality at low resolution scales.

Abstract

A framework to evolve three-nucleon (3N) forces in a plane-wave basis with the Similarity Renormalization Group (SRG) is presented and applied to consistent interactions derived from chiral effective field theory at next-to-next-to-leading order (N$^2$LO). We demonstrate the unitarity of the SRG transformation, show the decoupling of low and high momenta, and present the first investigation of universality in chiral 3N forces at low resolution scales. The momentum-space-evolved 3N forces are consistent and can be directly combined with the standard SRG-evolved two-nucleon (NN) interactions for ab-initio calculations of nuclear structure and reactions.