The Axial Glueball In Lattice Qcd

Using the t-expansion to order t7 the mass of the axial glueball in lattice QCD is investigated. The Padé approximants display a minimum around 2 GeV but have no extended scaling region. This result is consistent with the lack of scaling observed in Monte Carlo calculations in this channel. It also explains why hamiltonian strong-coupling calculations lead to non-trivial results. If scalling should set in at higher orders of the t-expansion, the minimum at 2 GeV could be indicative of the resulting mass-scale.