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Lattice hadron matrix elements with the Schroedinger functional: the case of the first moment of non-singlet quark density

M. Guagnelli·K. Jansen·R. Petronzio
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Abstract

We present the results of a non-perturbative determination of the pion matrix element of the twist-2 operator corresponding to the average momentum of non-singlet quark densities. The calculation is made within the Schroedinger functional scheme. We report the results of simulations done with the standard Wilson action and with the non-perturbatively improved clover action and we show that their ratio correctly extrapolates, in the continuum limit, to a value compatible with the residual correction factor expected from perturbation theory.

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M. Guagnelli, K. Jansen, R. Petronzio. 2000-09-07. Lattice hadron matrix elements with the Schroedinger functional: the case of the first moment of non-singlet quark density. https://doi.org/10.1016/s0370-2693(00)01138-2

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