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Investigation of the Second Moment of the Nucleon's g1 and g2 Structure Functions in Two-Flavor Lattice QCD

M. Göckeler·R. Horsley·D. Pleiter·P. E. L. Rakow·A. Schäfer·G. Schierholz·H. Stüben·J. M. Zanotti
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Abstract

The reduced matrix elements a_2 and d_2 are computed in lattice QCD with N_f=2 flavors of light dynamical (sea) quarks. For proton and neutron targets we obtain as our best estimates d_2^(p)=0.004(5) and d_2^(n)=-0.001(3), respectively, in the MSbar scheme at Q^2=5 GeV^2, while for a_2 we find a_2^(p)=0.077(12) and a_2^(n)=-0.005(5), where the errors are purely statistical.

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M. Göckeler, R. Horsley, D. Pleiter, P. E. L. Rakow, A. Schäfer, G. Schierholz, H. Stüben, J. M. Zanotti. 2005-09-05. Investigation of the Second Moment of the Nucleon's g1 and g2 Structure Functions in Two-Flavor Lattice QCD. https://doi.org/10.1103/physrevd.72.054507

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