Two-nucleon scattering in multiple partial waves

TL;DR

This paper uses lattice QCD to compute nucleon-nucleon scattering phase shifts across multiple partial waves at a high pion mass, employing finite volume methods to extract scattering parameters.

Contribution

It extends lattice QCD techniques to determine phase shifts in multiple partial waves at unphysical pion masses, utilizing a generalized Luscher's method on two volumes.

Findings

Phase shifts determined for S, P, D, and F waves.

Effective range expansion parameters extracted.

Method demonstrated at pion mass of ~800 MeV.

Abstract

We determine scattering phase shifts for S,P,D, and F partial wave channels in two-nucleon systems using lattice QCD methods. We use a generalization of Luscher's finite volume method to determine infinite volume phase shifts from a set of finite volume ground- and excited-state energy levels on two volumes, V=(3.4 fm)^3 and V=(4.5 fm)^3. The calculations are performed in the SU(3)-flavor limit, corresponding to a pion mass of approximately 800 MeV. From the energy dependence of the phase shifts we are able to extract scattering parameters corresponding to an effective range expansion.