O(alpha(2)(s)) contributions to charm production in charged-current deep-inelastic lepton-hadron scattering

The most important part of the order alpha(s)(2) corrections to the charm component of the charged-current structure functions F-2(x, Q(2)) and F-3(x, Q(2)) has been calculated. This calculation is based on the asymptotic form of the heavy-quark coefficient functions corresponding to the higher order corrections to the W-boson-gluon fusion process. These coefficient functions, which are in principle only valid for Q(2) much greater than m(2), can also be used to estimate the order alpha(s)(2) contributions at lower Q(2) values provided x < 0.1. It turns out that the above corrections are appreciable in the large Q(2) region and they explain the discrepancy found for the structure functions between the fixed-flavour scheme (FFS) and the variable-flavour-number scheme (VFNS). These corrections also hamper the extraction of the strange-quark density from the data obtained for the charged-current and the electromagnetic-current processes. (C) 1997 Elsevier Science B.V.