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Lorentz invariance relations for twist-3 quark distributions

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 نشر من قبل Fatma Aslan
 تاريخ النشر 2020
  مجال البحث
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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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