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arXiv · 2001.03655

Lorentz invariance relations for twist-3 quark distributions

Fatma P. Aslan·Matthias Burkardt
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Abstract

We calculate twist-3 parton ditribution functions (PDFs) using cut and uncut diagrams. Uncut diagrams lead to a Dirac delta function term. No such term appears when cut diagrams are used. We show that a $\delta(x)$ is necessary to satisfy the Lorentz invariance relations of twist-3 PDFs, except for the Burkhardt-Cottingham sum rule in QCD.

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Fatma P. Aslan, Matthias Burkardt. 2020-01-10. Lorentz invariance relations for twist-3 quark distributions. https://arxiv.org/abs/2001.03655

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