String breaking

TL;DR

This paper numerically studies the string breaking phenomenon in lattice QCD, analyzing energy levels, mixing, and action density to understand the transition from a static quark-antiquark string to a meson-antimeson system.

Contribution

It introduces improved noise reduction techniques enabling detailed observation of string breaking dynamics in Nf=2 lattice QCD at zero temperature.

Findings

Resolved string breaking signature in lattice QCD simulations.

Measured energy levels and mixing angles of the static two-state system.

Visualized action density distribution during string breaking.

Abstract

We numerically investigate the transition of the static quark-antiquark string into a static-light meson-antimeson system. Improving noise reduction techniques, we are able to resolve the signature of string breaking dynamics for Nf=2 lattice QCD at zero temperature. We discuss the lattice techniques used and present results on energy levels and mixing angle of the static two-state system. We visualize the action density distribution in the region of string breaking as a function of the static colour source-antisource separation. The results can be related to properties of quarkonium systems.