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Twist-2 Light-Ray Operators: Anomalous Dimensions and Evolution Equations

J. Blümlein·B. Geyer·D. Robaschik
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Abstract

The non-singlet and singlet anomalous dimensions of the twist--2 light-ray operators for unpolarized and polarized deep inelastic scattering are calculated in $O(α_s)$. We apply these results for the derivation of evolution equations for partition functions, structure functions, and wave functions which are defined as Fourier transforms of the matrix elements of the light-ray operators. Special cases are the Altarelli-Parisi and Brodsky-Lepage kernels. Finally we extend Radyushkin's solution from the non-singlet to the singlet case.

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J. Blümlein, B. Geyer, D. Robaschik. 1997-11-25. Twist-2 Light-Ray Operators: Anomalous Dimensions and Evolution Equations. https://arxiv.org/abs/hep-ph/9711405

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