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تسجيل مستخدم جديدOne-loop evolution of parton pseudo-distribution functions on the lattice
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Anatoly Radyushkin
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We incorporate recent calculations of one-loop corrections for the reduced Ioffe-time pseudo-distribution ${mathfrak M} ( u,z_3^2)$ to extend the leading-logarithm analysis of lattice data obtained by Orginos et al. We observe that the one-loop corrections contain a large term reflecting the fact that effective distances involved in the most important diagrams are much smaller than the nominal distance $z_3$. The large correction in this case may be absorbed into the evolution term, and the perturbative expansion used for extraction of parton densities at the $mu approx 2$ GeV scale is under control. The extracted parton distribution is rather close to global fits in the $x>0.1$ region, but deviates from them for $x<0.1$.
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