Pion wave function from lattice QCD vs. chiral quark models

TL;DR

This study compares the pion wave function from lattice QCD with predictions from chiral quark models, showing strong agreement and demonstrating how to extract transversity information relevant for light-cone physics.

Contribution

It provides the first detailed comparison of lattice QCD pion wave functions with chiral quark model predictions and shows how to obtain transversity info from equal-time lattice calculations.

Findings

Lattice QCD results agree well with Nambu--Jona-Lasinio model predictions.

Transversity information can be extracted from equal-time lattice calculations.

Quenched lattice QCD approximations are close to large-Nc limit of the model.

Abstract

We analyze the equal-time Bethe-Salpeter quark wave function of the pion obtained from a quenched lattice QCD calculation with delocalized quark interpolators. We find that the result agrees remarkably well with the predictions of the Nambu--Jona-Lasinio model in all channels. We choose the quenched lattice QCD, since it is closer to the large-Nc limit of the Nambu--Jona-Lasinio model. We also show how transversity information, relevant for the light-cone physics, can be obtained from our equal-time rest-frame lattice calculations.