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arXiv · hep-ph/0209100

Non-Singlet Structure Functions at Three Loops: Fermionic Contributions

Abstract

We compute the fermionic (n_f) contributions to the flavour non-singlet structure functions in unpolarized electromagnetic deep-inelastic scattering at third order of massless perturbative QCD. Complete results are presented for the corresponding nf-parts of the three-loop anomalous dimension and the three-loop coefficient functions for the structure functions F_2 and F_L. Our results agree with all partial and approximate results available in the literature. The present calculation also facilitates a complete determination of the threshold-resummation parameters B_2 and D_2^DIS of which only the sum was known so far, thus completing the information required for the next-to-next-to-leading logarithmic resummation. We find that D_2^DIS vanishes in the MSbar scheme.

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BibTeXRIS

S. Moch, J. A. M. Vermaseren, A. Vogt. 2002-09-10. Non-Singlet Structure Functions at Three Loops: Fermionic Contributions. https://doi.org/10.1016/s0550-3213(02)00870-2

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