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Staggered Baryon Operators with Flavor SU(3) Quantum Numbers

Jon A. Bailey
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Abstract

The construction of the first baryon operators for staggered lattice QCD exploited the taste symmetry to emulate physical quark flavor; contemporary 2+1 flavor simulations explicitly include three physical quark flavors and necessitate interpreting a valence sector with twelve quarks. After discussing expected features of the resulting baryon spectrum, I consider the spectra of operators transforming irreducibly under SU(3)xGTS, the direct product of flavor SU(3) and the geometrical time-slice group of the 1-flavor staggered theory. I then describe the construction of a set of maximally local baryon operators transforming irreducibly under SU(3)xGTS and enumerate this set. In principle, the operators listed here could be used to extract the masses of all the lightest spin-1/2 and spin-3/2 baryon resonances of staggered QCD. Using appropriate operators from this set in partially quenched simulations should allow for particularly clean 2+1 flavor calculations of the masses of the nucleon and the lightest decuplet.

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Jon A. Bailey. 2007-04-06. Staggered Baryon Operators with Flavor SU(3) Quantum Numbers. https://doi.org/10.1103/physrevd.75.114505

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