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arXiv · 2201.06519

Proton generalized parton distributions from lattice QCD

Aurora Scapellato·Constantia Alexandrou·Krzysztof Cichy·Martha Constantinou·Kyriakos Hadjiyiannakou·Karl Jansen·Fernanda Steffens
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Abstract

Momentum and spatial distributions of quarks and gluons inside hadrons are typically encoded in the so-called generalized parton distributions (GPDs). GPDs are multi-dimensional quantities that are very challenging to extract, both experimentally and within lattice QCD. We present the first lattice results on the $x$-dependence of isovector unpolarized, helicity and transversity GPDs of the proton, obtained from lattice QCD using an ensemble of $N_f=2+1+1$ maximally twisted mass fermions, with pion mass $M_\pi=260$ MeV and lattice spacing $a\simeq 0.093$ fm. Our calculations use the quasi-distribution formalism and the final distributions are presented in the MS-bar scheme at a renormalization scale of 2 GeV.

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Aurora Scapellato, Constantia Alexandrou, Krzysztof Cichy, Martha Constantinou, Kyriakos Hadjiyiannakou, Karl Jansen, Fernanda Steffens. 2022-01-17. Proton generalized parton distributions from lattice QCD. https://arxiv.org/abs/2201.06519

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