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arXiv · 2307.07904

The Compton amplitude and nucleon structure functions in lattice QCD

K. U. Can·M. Batelaan·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

The structure of hadrons relevant for deep-inelastic scattering are completely characterised by the Compton amplitude. A direct calculation of the Compton amplitude in a lattice QCD setup provides a way to accessing the structure functions, circumventing the operator mixing and renormalisation issues of the standard operator product expansion approach. In this contribution, we focus on the QCDSF/UKQCD Collaboration's advances in calculating the forward Compton amplitude via an implementation of the second-order Feynman-Hellmann theorem. We highlight our progress in investigating the moments of nucleon structure functions.

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K. U. Can, M. Batelaan, A. Hannaford-Gunn, R. Horsley, Y. Nakamura, H. Perlt, P. E. L. Rakow, G. Schierholz, H. Stüben, R. D. Young, J. M. Zanotti. 2023-07-15. The Compton amplitude and nucleon structure functions in lattice QCD. https://arxiv.org/abs/2307.07904

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