Nuclear force with LapH smearing

TL;DR

This paper introduces a novel LapH smearing technique combined with the HAL QCD method to improve the accuracy and efficiency of calculating nuclear forces in lattice QCD simulations.

Contribution

The paper presents a new smearing method based on Laplacian eigenvectors that reduces errors and computational costs in nuclear force calculations.

Findings

Reduced statistical errors in nuclear force calculations

Lower systematic errors achieved with the new smearing technique

More efficient computation of hadron correlators

Abstract

The nuclear forces are determined by combining the HAL QCD method and a new type of source smearing technique. The new smearing is a projection to a space spanned by the lowest-lying eigenvectors of the free Laplacian operator on a lattice, which enables efficient calculation of hadron correlators at an affordable cost by utilizing the hadron-level momentum conservations. We find that this new approach reduces the statistical and systematic errors in the resultant nuclear forces.