Non-singlet structure functions at three loops: Fermionic contributions

S. Moch, J.A.M. Vermaseren, A. Vogt
2002 Nuclear Physics B  
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
more » ... ates 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.
doi:10.1016/s0550-3213(02)00870-2 fatcat:s35wsz24izcdde2cjzago2cyny