Open charm and beauty production in photon-photon collisions at L3

Inclusive heavy flavour production in gamma gamma collisions has been studied with the L3 detector at the LEP collider. Preliminary results on charm and beauty production at square root (s)=189 GeV are presented. Hadronic final states containing charm particles were identified either by detecting electrons or muons from their semi- leptonic decays or by reconstruction of charged D* meson decays. The cross section for beauty production in gamma gamma collisions has been measured for the first time. Even including real and virtual gluon emission (NLO QCD) the direct process gamma gamma to cc, bb is insufficient to describe charm and beauty production in gamma gamma collisions. The cross section values and event distributions require resolved processes, sensitive to the gluon density function of the photon. (23 refs).