Confining string and its widening in HP1 embedding approach

TL;DR

This study investigates the structure and widening of the confining string in SU(2) Yang-Mills theory using the HP1 sigma-model embedding, revealing Gaussian profiles and logarithmic widening consistent with Luscher's predictions.

Contribution

It introduces a novel analysis of the confining string's topological and action densities using the HP1 embedding approach, confirming the Luscher widening effect.

Findings

The confining flux tube suppresses topological charge and action densities.

String cross section follows a Gaussian profile beyond formation length.

String width increases logarithmically with string length.

Abstract

Structure of confining string in terms of the topological charge density and the action density is studied in SU(2) Yang-Mills theory on the lattice using HP1 sigma-model embedding approach. We find that the confining flux tube noticeably suppresses both the topological charge and the action densities. Beyond the string formation length the string cross section in terms of these quantities is well described by a Gaussian profile. In both cases the squared string width is found to be a logarithmic function of the string length confirming the Luscher widening of the chromoelectric string. Characteristic string scales in terms of the topological and action densities are estimated as well.