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Moments $n=2$ and $n=3$ of the Wilson twist-two operators at three loops in the RI${}$/SMOM scheme

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 نشر من قبل Bernd Kniehl
 تاريخ النشر 2020
  مجال البحث
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We study the renormalization of the matrix elements of the twist-two non-singlet bilinear quark operators, contributing to the $n=2$ and $n=3$ moments of the structure functions, at next-to-next-to-next-to-leading order in QCD perturbation theory at the symmetric subtraction point. This allows us to obtain conversion factors between the $overline{rm MS}$ scheme and the regularization-invariant symmetric momentum subtraction (RI/SMOM, RI${}$/SMOM) schemes. The obtained results can be used to reduce errors in determinations of moments of structure functions from lattice QCD simulations. The results are given in Landau gauge.

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