The eta-prime meson with staggered fermions

We have computed the eta-prime pseudoscalar octet mass splitting using staggered fermions on both dynamical and quenched gauge configurations. We have used Wuppertal smeared operators to reduce excited state contributions. We compare our results with the theoretical forms predicted by partially quenched chiral perturbation theory in the lowest order. Using lattice volumes of size 16^3 x 32 with a^{-1}=2GeV we obtain results consistent with the physical eta-prime mass. We also demonstrate that the flavor singlet piece of the eta-prime mass comes from zero modes of the Dirac operator.