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arXiv · 1207.1110

_{u-d} from lattice QCD at nearly physical quark masses

Gunnar S. Bali·Sara Collins·Mridupawan Deka·Benjamin Glaessle·Meinulf Gockeler·Johannes Najjar·Andrea Nobile·Dirk Pleiter·Andreas Schafer·Andre Sternbeck
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Abstract

We determine the second Mellin moment of the isovector quark parton distribution function _{u-d} from lattice QCD with N_f=2 sea quark flavours, employing the non-perturbatively improved Wilson-Sheikholeslami-Wohlert action at a pseudoscalar mass of 157(6) MeV. The result is converted non-perturbatively to the RI'-MOM scheme and then perturbatively to the MSbar scheme at a scale mu = 2 GeV. As the quark mass is reduced we find the lattice prediction to approach the value extracted from experiments.

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Gunnar S. Bali, Sara Collins, Mridupawan Deka, Benjamin Glaessle, Meinulf Gockeler, Johannes Najjar, Andrea Nobile, Dirk Pleiter, Andreas Schafer, Andre Sternbeck. 2012-09-11. _{u-d} from lattice QCD at nearly physical quark masses. https://doi.org/10.1103/physrevd.86.054504

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