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arXiv · 1310.4263

Gluon Helicity Delta G from a Universality Class of Operators on a Lattice

Yoshitaka Hatta·Xiangdong Ji·Yong Zhao
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Abstract

We show that the total gluon helicity $ΔG$ in a polarized nucleon can be calculated on a Euclidean lattice through a universality class of QCD operators that describe the helicity or polarization of the onshell gluon radiation. We in particular find some operators whose matrix elements in a nucleon of momentum $P^z$ are directly related to $ΔG$ with only power-law $(1/P^z)^n (n\ge 2)$ corrections.

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Yoshitaka Hatta, Xiangdong Ji, Yong Zhao. 2013-10-16. Gluon Helicity Delta G from a Universality Class of Operators on a Lattice. https://doi.org/10.1103/physrevd.89.085030

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