Precise treatment of operator mixing in application of asymptotically free theories to deep-inelastic scattering

Operator mixing has been the source of serious uncertainties in quantitative studies of the q2 dependence of structure functions. We formulate a procedure for treating twist-2 operator mixing which allows the general problem to be solved with the same precision as the case without operator mixing. Singlet quark- and gluon-operator mixing is studied in this approach. Salient features of the solution are presented. Comparison of these new results with approximations in the existing literature is made. This method, when applied to a detailed phenomenological analysis of deep-inelastic scattering data, should yield information on the gluon distribution function, an important ingredient in all parton-model calculations, which is unobservable except through scaling-violation effects