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Analysis of $N^{\star}$ spectra using matrices of correlation functions based on irreducible baryon operators

LHP Collaboration·S. Basak·I. Sato·S. Wallace·R. Edwards·G. T. Fleming·D. Richards·R. Fiebig·U. M. Heller·C. Morningstar
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Abstract

We present results for ground and excited-state nucleon masses in quenched lattice QCD using anisotropic lattices. Group theoretical constructions of local and nonlocal straight-link irreducible operators are used to obtain suitable sources and sinks. Matrices of correlation functions are diagonalized to determine the eigenvectors. Both chi-square fitting and Bayesian inference with an entropic prior are used to extract masses from the correlation functions in a given channel. We observe clear separation of the excited state masses from the ground state mass. States of spin >= 5/2 have been isolated by use of G_2 operators.

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LHP Collaboration, S. Basak, I. Sato, S. Wallace, R. Edwards, G. T. Fleming, D. Richards, R. Fiebig, U. M. Heller, C. Morningstar. 2004-09-15. Analysis of $N^{\star}$ spectra using matrices of correlation functions based on irreducible baryon operators. https://doi.org/10.1016/j.nuclphysbps.2004.11.170

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