PS04 Hard QCD
Bottom and charm quark production in two-photon collisions at LEP
LPNHE CNRS/IN2P3 Universités P6 and P7, Paris, France
Accepted: 20 January 2004
Published online: 3 March 2004
Heavy b and c quark production in γ γ collisions has been measured at LEP. We report here the cross sections measurement and made by DELPHI and L3 Collaboration. Inclusive D *± (J/ ψ) has also been studied by L3 (DELPHI). The cross section for b production is found to exceed QCD predictions. The new DELPHI analysis using for the first time K-lepton double tagging in γ γ physics confirms this excess.
© Società Italiana di Fisica, Springer-Verlag, 2004