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arXiv · 2201.02181

Parton distribution function for topological charge at one loop

Anatoly Radyushkin·Shuai Zhao
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Abstract

We present results for the $gg$-part of the one-loop corrections to the recently introduced "topological charge" GPD $\widetilde F(x,q^2)$. In particular, we give expression for its evolution kernel. To enforce strict compliance with the gauge invariance requirements, we have used on-shell states for external gluons, and have obtained identical results both in Feynman and light-cone gauges. No "zero mode" $\delta (x)$ terms were found for the twist-4 gluon GPD $\widetilde F(x,q^2)$.

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Anatoly Radyushkin, Shuai Zhao. 2022-01-06. Parton distribution function for topological charge at one loop. https://doi.org/10.1007/jhep02(2022)163

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