Second-order quasiparticle interaction in nuclear matter with chiral two-nucleon interactions

TL;DR

This paper uses Landau's Fermi liquid theory with chiral two-nucleon interactions to derive second-order quasiparticle interactions in nuclear matter, providing new insights into Landau parameters and the role of three-nucleon forces.

Contribution

First exact second-order calculations of quasiparticle interactions in nuclear matter using chiral potentials, including analysis of scale dependence and three-nucleon forces.

Findings

Derived Landau parameters L=0 and L=1 at second order.

Analyzed scale dependence of quasiparticle interactions.

Highlighted importance of three-nucleon forces in effective interactions.

Abstract

We employ Landau's theory of normal Fermi liquids to study the quasiparticle interaction in nuclear matter in the vicinity of saturation density. Realistic low-momentum nucleon-nucleon interactions evolved from the Idaho N3LO chiral two-body potential are used as input potentials. We derive for the first time exact results for the central part of the quasiparticle interaction computed to second order in perturbation theory, from which we extract the L=0 and L=1 Landau parameters as well as some relevant bulk equilibrium properties of nuclear matter. The accuracy of the intricate numerical calculations is tested with analytical results derived for scalar-isoscalar boson exchange and (modified) pion exchange at second order. The explicit dependence of the Fermi liquid parameters on the low-momentum cutoff scale is studied, which provides important insight into the scale variation of phase-shift equivalent two-body potentials. This leads naturally to explore the role that three-nucleon forces must play in the effective interaction between two quasiparticles.