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arXiv · hep-lat/0103038

A lattice evaluation of four-quark operators in the nucleon

M. Göckeler·R. Horsley·B. Klaus·D. Pleiter·P. E. L. Rakow·S. Schaefer·A. Schäfer·G. Schierholz
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Abstract

Nucleon matrix elements of various four-quark operators are evaluated in quenched lattice QCD using Wilson fermions. Some of these operators give rise to twist-four contributions to nucleon structure functions. Furthermore, they bear valuable information about the diquark structure of the nucleon. Mixing with lower-dimensional operators is avoided by considering appropriate representations of the flavour group. We find that for a certain flavour combination of baryon structure functions, twist-four contributions are very small. This suggests that twist-four effects for the nucleon might be much smaller than m_p^2/Q^2.

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M. Göckeler, R. Horsley, B. Klaus, D. Pleiter, P. E. L. Rakow, S. Schaefer, A. Schäfer, G. Schierholz. 2001-03-30. A lattice evaluation of four-quark operators in the nucleon. https://doi.org/10.1016/s0550-3213(01)00631-9

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