Charm in the nucleon
1 Instituto de Fisica - USP,
C.P. 66 318, 05315-970,
2 Institut für Kernphysik, Forschungszentrum Jülich, 52425 Jülich, Germany
3 Department of Physics and Mathematical Physics, and Special Research Center for the Subatomic Structure of Matter, University of Adelaide, 5005, Australia
Received: 22 March 1999 / Revised version: 11 June 1999 / Published online: 3 November 1999
A next-to-leading order analysis of inelastic electroproduction of charm is performed using an interpolating scheme which maps smoothly onto massless QCD evolution at large Q2 and photon-gluon fusion at small Q2. In contrast with earlier analyses, this scheme allows the inclusion of quark and target mass effects and heavy quark thresholds, as well as possible non-perturbative, or intrinsic, charm contributions. We find no conclusive evidence in favor of an intrinsic charm component in the nucleon, although several data points which disagree with perturbative QCD expectations will need to be checked by future experiments.