Quark Model from Lattice QCD

TL;DR

This paper investigates the valence quark structure of hadrons using lattice QCD, showing that certain matrix element ratios align with SU(6) quark model predictions when backward time propagation is truncated.

Contribution

It introduces a valence approximation in lattice QCD by truncating backward time propagation, providing insights into hadron structure and mass effects.

Findings

Ratios of isovector to isoscalar matrix elements match SU(6) predictions

Valence approximation reproduces key quark model features

Discussion on how hadron masses are influenced

Abstract

We study the valence approximation in lattice QCD of hadrons where the cloud quarks and antiquarks are deleted by truncating the backward time propagation (Z graphs) in the connected insertions. Whereas, the sea quarks are eliminated via the quenched approximation and in the disconnected insertions. It is shown that the ratios of isovector to isoscalar matrix elements in the nucleon reproduce the SU(6) quark model predictions in a lattice QCD calculation. We also discuss how the hadron masses are affected.