Structure and flow of the nucleon eigenstates in lattice QCD

A determination of the excited energy eigenstates of the nucleon, s = 1/2, I = 1/2, N+, is presented in full QCD using 2 + 1 flavor PACS-CS gauge configurations. The correlation-matrix method is used and is built using standard nucleon interpolators employing smearings at the fermion sources and sinks. We develop and demonstrate a new technique that allows the eigenvectors obtained to be utilized to track the propagation of the intrinsic nature of energy states from one quark mass to the next. This approach is particularly useful for larger dimension correlation matrices where more near-degenerate energy states can appear in the spectrum.