Measurement of the Charm Structure Function of the Photon at Lep
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چکیده
Charm production is studied in deep-inelastic electron-photon scattering using OPAL data at ee centre-of-mass energies from 183 to 209 GeV. Charm quarks are identified by exclusive reconstruction of D mesons. The cross-section of D production is measured in a restricted kinematic region, and then extrapolated to the total charm production cross-section and the charm structure function of the photon. For x > 0.1 the measurement is well described by Monte Carlo models and perturbative QCD calculations but for x < 0.1 the predictions are lower than the data both in the directly measured region and after the extrapolation.
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تاریخ انتشار 2001