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arXiv · hep-ph/9912379

Evolution kernels of skewed parton distributions: method and two-loop results

A. V. Belitsky·A. Freund·D. Müller
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Abstract

We present a formalism and explicit results for two-loop flavor singlet evolution kernels of skewed parton distributions in the minimal subtraction scheme. This approach avoids explicit multiloop calculations in QCD and is based on the known pattern of conformal symmetry breaking in this scheme as well as constraints arising from the graded algebra of the $\cN = 1$ super Yang-Mills theory. The conformal symmetry breaking part of the kernels is deduced from commutator relations between scale and special conformal anomalies while the symmetric piece is recovered from the next-to-leading order splitting functions and $\cN = 1$ supersymmetry relations.

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A. V. Belitsky, A. Freund, D. Müller. 1999-12-16. Evolution kernels of skewed parton distributions: method and two-loop results. https://doi.org/10.1016/s0550-3213(00)00012-2

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