N* Mass Spectrum from an Anisotropic Action

Results are reported for N* masses in the 1/2+ and 1/2− sectors on an anisotropic lattice. The gauge action is the usual plaquette plus rectangle type, the quark action is of the D234 type, both having tadpole-improved tree-level coefficients. Clear splittings from the nucleon ground state are observed with smeared operators and 500 configurations. The first excited states in each channel are further isolated, using a correlation matrix and the variational method. The basic pattern of these splittings is consistent with experimental observations.