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arXiv · 2209.04141

Moments and power corrections of longitudinal and transverse proton structure functions from lattice QCD

M. Batelaan·K. U. Can·A. Hannaford-Gunn·R. Horsley·Y. Nakamura·H. Perlt·P. E. L. Rakow·G. Schierholz·H. Stüben·R. D. Young·J. M. Zanotti
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Abstract

We present a simultaneous extraction of the moments of $F_2$ and $F_L$ structure functions of the proton for a range of photon virtuality, $Q^2$. This is achieved by computing the forward Compton amplitude on the lattice utilizing the second-order Feynman-Hellmann theorem. Our calculations are performed on configurations with two different lattice spacings and volumes, all at the $SU(3)$ symmetric point. We find the moments of $F_{2}$ and $F_{L}$ in good agreement with experiment. Power corrections turn out to be significant. This is the first time the $Q^2$ dependence of the lowest moment of $F_2$ has been quantified.

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M. Batelaan, K. U. Can, A. Hannaford-Gunn, R. Horsley, Y. Nakamura, H. Perlt, P. E. L. Rakow, G. Schierholz, H. Stüben, R. D. Young, J. M. Zanotti. 2022-09-09. Moments and power corrections of longitudinal and transverse proton structure functions from lattice QCD. https://doi.org/10.1103/physrevd.107.054503

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