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arXiv · 1612.08336

Nucleon-pion-state contribution in lattice calculations of moments of parton distribution functions

Oliver Bar
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Abstract

We employ chiral perturbation theory to calculate the nucleon-pion-state contribution to the 3-point correlation functions measured in lattice QCD to compute various moments of parton distribution functions (quark momentum fraction, helicity and transversity moment). We estimate the impact of the nucleon-pion-state contribution on the plateau method for lattice simulations with a physical pion mass. The nucleon-pion-state contribution results in an overestimation of all three moments. The overestimation is at the 5-20% level for source-sink separations of about 1.5 fm.

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Oliver Bar. 2016-12-26. Nucleon-pion-state contribution in lattice calculations of moments of parton distribution functions. https://doi.org/10.1103/physrevd.95.034506

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