Extracting the h′ meson mass from gluonic correlators in lattice QCD

Abstract

Calculation of the h′ meson mass is a notoriously difficult problem, as it requires evaluation of the disconnected diagram which is costly and noisy. In this work, we use a gluonic operator to extract the eta-prime state after smearing the link variables through the Wilson flow. With this choice, one can avoid a large cancellation of pION contribution between the connected and disconnected diagrams. We obtain the h′ meson mass on lattices with three different lattice spacings and two physical volumes, which allow us to estimate its continuum and large volume limits.