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Photon Structure and Heavy Flavour Production in gammagamma Collisions at LEP

Armin Böhrer
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Abstract

New results reported at the Moriond-QCD 2003 conference from the experiments ALEPH, DELPHI, L3, and OPAL on the structure of the photon as well as heavy quark production in gammagamma collisions are presented. The hadronic structure of the photon is studied in single-tagged events; the interaction of two virtual photons is investigated in double-tagged events. Di-jet events allow, besides constraining the photon structure, investigations on the structure of jets, measurement of the di-jet as well as inclusive and differential cross sections. Inclusive charm and bottom production are investigated at LEP~2 energies. The total and differential cross sections for charm quarks are now measured by all four LEP collaborations, the total bottom by two. Charmonia are detected inclusively via the muonic decay of the J/psi and separated for the resolved and diffractive processes. Updated results are available for exclusive production of the eta_c meson. The search for exclusive eta_b production is presented.

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Armin Böhrer. 2003-05-14. Photon Structure and Heavy Flavour Production in gammagamma Collisions at LEP. https://arxiv.org/abs/hep-ex/0305029

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