Isoscalar meson spectroscopy from lattice QCD

Abstract

We extract to high statistical precision an excited spectrum of single-particle isoscalar mesons using lattice QCD, including states of high spin and, for the first time, light exotic ${J}^{\mathrm{PC}}$ isoscalars. The use of a novel quark field construction has enabled us to overcome the long-standing challenge of efficiently including quark-annihilation contributions. Hidden-flavor mixing angles are extracted and while most states are found to be close to ideally flavor mixed, there are examples of large mixing in the pseudoscalar and axial sectors in line with experiment. The exotic ${J}^{\mathrm{PC}}$ isoscalar states appear at a mass scale comparable to the exotic isovector states.