Lattice QCD computation of the colour fields for the static hybrid quark-gluon-antiquark system, and microscopic study of the Casimir scaling

TL;DR

This study uses lattice QCD to analyze the chromoelectric and chromomagnetic fields in a static hybrid quark-gluon-antiquark system, providing insights into confinement, flux tubes, and Casimir scaling relevant for understanding hadron structure.

Contribution

It presents the first detailed lattice QCD computation of the colour fields for a static hybrid system with different geometries, exploring Casimir scaling microscopically.

Findings

Casimir scaling observed in the colour fields.

Flux tube structures depend on the geometry of the static sources.

Insights into hybrid meson structure and confinement mechanisms.

Abstract

The chromoelectric and chromomagnetic fields, created by a static gluon-quark-antiquark system, are computed in quenched SU(3) lattice QCD, in a $24^3\times 48$ lattice at $\beta=6.2$ and $a=0.07261(85) fm$. We compute the hybrid Wilson Loop with two spatial geometries, one with a U shape and another with an L shape. The particular cases of the two gluon glueball and quark-antiquark are also studied, and the Casimir scaling is investigated in a microscopic perspective. This microscopic study of the colour fields is relevant to understand the structure of hadrons, in particular of the hybrid excitation of mesons. This also contributes to understand confinement with flux tubes and to discriminate between the models of fundamental versus adjoint confining strings, analogous to type-II and type-I superconductivity.