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Moments of singlet parton densities on the lattice in the Schroedinger Functional scheme

F. Palombi·R. Petronzio·A. Shindler
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Abstract

A non perturbative computation of the evolution of singlet parton densities without gauge--fixing requires a gauge invariant gluon source operator. Within the Schrödinger Functional scheme (SF), such a source can be defined in terms of path ordered products of gauge links, connected to the time boundaries. In this paper we adopt this definition and perform a one loop lattice computation of the renormalization constants of the twist--2 operators that correspond to the second moment of singlet parton densities. This calculation fixes the connection between the lattice SF scheme where a non perturbative evaluation of the absolute normalization of singlet parton densities can be made at low energy and the $\bar{MS}$ scheme where one can extract the experimental values.

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F. Palombi, R. Petronzio, A. Shindler. 2002-03-05. Moments of singlet parton densities on the lattice in the Schroedinger Functional scheme. https://doi.org/10.1016/s0550-3213(02)00407-8

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