Glueball mass measurements from improved staggered fermion simulations

TL;DR

This study uses high-statistics lattice QCD simulations with improved staggered fermions to measure the spectrum of glueball states in 2+1 flavor QCD, providing insights into their masses and couplings.

Contribution

First 2+1 flavor glueball spectrum measurements using improved staggered fermions with high statistics and multiple lattice spacings.

Findings

Spectrum consistent with quenched measurements for scalar, pseudoscalar, and tensor glueballs.

Evidence of coupling to 2-pion states.

Comparison with experimental glueball candidates and quenched estimates.

Abstract

We present the first 2+1 flavour spectrum measurements of glueball states using high statistics simulations with improved staggered fermions. We find a spectrum consistent with quenched measurements of scalar, pseudoscalar andtensor glueball states. The measurements were made using 5000 configurations at a lattice spacing of 0.123 fm and pion mass of 280 MeV and 3000 configurations at 0.092 fm with a pion mass of 360 MeV. We see some evidence of coupling to 2 pion states. We compare our results with the experimental glueball candidate spectrum as well as quenched glueball estimates.