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arXiv · hep-lat/9908011

Higher-Twist Contribution to Pion Structure Function: 4-Fermi Operators

S. Capitani·M. Göckeler·R. Horsley·B. Klaus·V. Linke·P. E. L. Rakow·A. Schäfer·G. Schierholz
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Abstract

We present quenched lattice QCD results for the contribution of higher-twist operators to the lowest non-trivial moment of the pion structure function. To be specific, we consider the combination $F_2^{π^+} + F_2^{π^-} - 2 F_2^{π^0}$ which has $I = 2$ and receives contributions from 4-Fermi operators only. We introduce the basis of lattice operators. The renormalization of the operators is done perturbatively in the $\bar{\rm{MS}}$ scheme using the 't Hooft-Veltman prescription for $γ_5$, taking particular care of mixing effects. The contribution is found to be of $O(f_π^2/Q^2)$, relative to the leading contribution to the moment of $F_2^{π^+}$.

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BibTeXRIS

S. Capitani, M. Göckeler, R. Horsley, B. Klaus, V. Linke, P. E. L. Rakow, A. Schäfer, G. Schierholz. 1999-12-30. Higher-Twist Contribution to Pion Structure Function: 4-Fermi Operators. https://doi.org/10.1016/s0550-3213(99)00815-9

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