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Lattice QCD determination of states with spin 5/2 or higher in the spectrum of nucleons

S. Basak·R. G. Edwards·G. T. Fleming·A. Lichtl·C. Morningstar·D. G. Ricards·I. Sato·S. J. Wallace
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Abstract

Energies for excited isospin 1/2 states that include the nucleon are computed using quenched, anisotropic lattices. Baryon interpolating field operators that are used include nonlocal operators that provide $G_2$ irreducible representations of the octahedral group. The decomposition of spin 5/2 or higher states is realized for the first time in a lattice QCD calculation. We observe patterns of degenerate energies in the irreducible representations of the octahedral group that correspond to the subduction of the continuum spin 5/2 or higher.

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S. Basak, R. G. Edwards, G. T. Fleming, A. Lichtl, C. Morningstar, D. G. Ricards, I. Sato, S. J. Wallace. 2006-09-26. Lattice QCD determination of states with spin 5/2 or higher in the spectrum of nucleons. https://arxiv.org/abs/hep-lat/0609052

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