Baryons in the light-front approach: The three-quark picture

TL;DR

This paper develops a light-front three-quark model for baryons, clarifies its relation to the diquark picture, and highlights the importance of Lorentz boosts, proposing a framework extendable to multiquark states.

Contribution

It introduces a bottom-up approach to model baryons in the light-front quark model, connecting three-quark and diquark pictures, and generalizes to multiquark states.

Findings

Determined shape parameters using baryon pole residues.

Clarified the relation between three-quark and diquark pictures.

Proposed a unified framework for multiquark states.

Abstract

In this work, a three-quark picture is constructed using a bottom-up approach for baryons in light-front quark model. The shape parameters, which characterize the momentum distribution inside a baryon, are determined with the help of the pole residue of the baryon. The relation between the three-quark picture and the diquark picture is clarified. When building the model, we find that Lorentz boost plays a crucial role, and the bottom-up modeling approach can be generalized to multiquark states. Based on this, a unified theoretical framework for describing multiquark states may be established. As a by-product of model construction, we can easily obtain a newly improved definition of baryon interpolating current. The hadron interpolating currents are the starting point of Lattice QCD and QCD sum rules, and therefore are of great importance.