Scalar and Pseudoscalar Glueball Masses within a Gaussian Wavefunctional Approximation

TL;DR

This paper calculates the lowest scalar and pseudoscalar glueball masses in Yang-Mills theory using a Gaussian wavefunctional approximation, revealing their dependence on the QCD coupling constant.

Contribution

It introduces a time-dependent variational approach within a Gaussian approximation to evaluate glueball masses as poles of the propagator in Yang-Mills theory.

Findings

Finite glueball masses are obtained from gluon interactions.

Glueball masses depend nonperturbatively on the QCD coupling g.

Method provides a new way to estimate glueball properties.

Abstract

The lowest scalar and pseudoscalar glueball masses are evaluated by means of the time-dependent variational approach to the Yang-Mills gauge theory without fermions in the Hamiltonian formalism within a Gaussian wavefunctional approximation. The glueball mass is calculated as a pole of the propagator for a composite glueball field which consists of two massless gluons. The glueball propagator is here evaluated by using the linear response theory for the composite external glueball field. As a result, a finite glueball mass is obtained through the interaction between two massless gluons, in which the glueball mass depends on the QCD coupling constant g in the nonperturbative form.