Yang-Mills glueball masses from spectral reconstruction

TL;DR

This paper calculates the masses of the two lightest glueballs in Yang-Mills theory using spectral reconstruction techniques applied to functional renormalisation group data, aligning with previous lattice and bound state results.

Contribution

It introduces a novel spectral reconstruction approach using Gaussian process regression to determine glueball masses from functional renormalisation group data in Landau gauge Yang-Mills theory.

Findings

The scalar glueball mass is approximately 1870 MeV.

The pseudoscalar glueball mass is approximately 2700 MeV.

Results agree with existing lattice and bound state calculations.

Abstract

We compute masses of the two lightest glueballs from spectral reconstructions of timelike interaction channels of the four-gluon vertex in Landau gauge Yang-Mills theory. The Euclidean spacelike dressings of the vertex are calculated with the functional renormalisation group. For the spectral reconstruction of these Euclidean data, we employ Gaussian process regression. The glueball resonances can be identified straightforwardly and we obtain $m_{sc} = 1870(75)~$ MeV as well as $m_{ps} = 2700(120)~$ MeV, in accordance with functional bound state and lattice calculations.