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Towards a determination of the spectrum of QCD using a space-time lattice

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

Progress by the Lattice Hadron Physics Collaboration in determining the baryon and meson resonance spectrum of QCD using Monte Carlo methods with space-time lattices is described. The extraction of excited-state energies necessitates the evaluation of correlation matrices of sets of operators, and the importance of extended three-quark operators to capture both the radial and orbital structures of baryons is emphasized. The use of both quark-field smearing and link-field smearing in the operators is essential for reducing the couplings of the operators to the high-frequency modes and for reducing statistical noise in the correlators. The extraction of nine energy levels in a given symmetry channel is demonstrated, and identifying the continuum spin quantum numbers of the levels is discussed.

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K. J. Juge, A. Lichtl, C. Morningstar, R. G. Edwards, D. G. Richards, S. Basak, S. Wallace, I. Sato, G. T. Fleming. 2006-01-23. Towards a determination of the spectrum of QCD using a space-time lattice. https://doi.org/10.1142/9789812773333_0022

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