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Observing Chiral Nonanalytic Behavior with FLIC Fermions

D. B. Leinweber·A. W. Thomas·A. G. Williams·R. D. Young·J. M. Zanotti·J. B. Zhang
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Abstract

First results from lattice QCD revealing the chiral nonanalytic behavior of nucleon and Delta baryon magnetic moments are presented. Numerical simulations in the light quark mass regime employing the nonperturbatively O(a)-improved conserved vector current are enabled via FLIC fermions. Quenched chiral perturbation theory for the nucleon and Delta magnetic moments is derived to next to next to leading nonanalytic order. Numerical simulation results for the proton and Delta baryon magnetic moments in quenched QCD reveal dramatic signatures of the quenched meson cloud, which are in accord with the predictions of quenched chiral perturbation theory.

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D. B. Leinweber, A. W. Thomas, A. G. Williams, R. D. Young, J. M. Zanotti, J. B. Zhang. 2003-08-29. Observing Chiral Nonanalytic Behavior with FLIC Fermions. https://doi.org/10.1016/j.nuclphysa.2004.03.060

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