Determination of the anomalous dimension of gluonic operators in deep inelastic scattering at O(1/Nf)

Using large Nf methods we compute the anomalous dimension of the predominantly gluonic flavour singlet twist-2 composite operator which arises in the operator product expansion used in deep inelastic scattering. We obtain a d-dimensional expression for it which depends on the operator moment n. Its expansion in powers of epsilon = (4 - d)/2 agrees with the explicit exact three-loop <(MS)over bar> results available for n less than or equal to 8 and allows us to determine some new information on the explicit n-dependence of the three and higher order coefficients. In particular the n-dependence of the three-loop anomalous dimension gamma(gg)(a) is determined in the C-2(G) sector at O(1/N-f). (C) 1998 Elsevier Science B.V.