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arXiv · hep-ph/9705317

Purely-Nonperturbative Composite Operators and Parton Distributions

Xiangdong Ji
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Abstract

A class of purely-nonperturbative (PNP) composite operators is defined in Quantum Chromodynamics, which is perturbative scheme and scale independent and are useful to describe the internal structure of a strong interacting system. The operator product expansion in terms of the new operators cleanly separates the perturbative and nonperturbative physics without introducing any factorization scale. A number of PNP observables of the nucleon is briefly discussed including the PNP parton distributions. In particular, the fraction of the nucleon momentum carried by the purely-nonperturbative gluons is found to be around 16%.

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Xiangdong Ji. 1997-05-14. Purely-Nonperturbative Composite Operators and Parton Distributions. https://arxiv.org/abs/hep-ph/9705317

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