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Measurement of the Hadronic Photon Structure Function F2gamma at LEP2

The OPAL collaboration·G. Abbiendi
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Abstract

The hadronic structure of the photon F2gamma is measured as a function of Bjorken x and of the photon virtuality Q2 using deep-inelastic scattering data taken by the OPAL detector at LEP at e+e- centre-of-mass energies from 183 to 209 GeV. Previous OPAL measurements of the x dependence of F2gamma are extended to an average Q2 of =780GeV2 using data in the kinematic range 0.15 < x < 0.98. The Q2 evolution of F2gamma is studied for 12.1 < < 780GeV2 using three ranges of x. As predicted by QCD, the data show positive scaling violations in F2gamma for the central x region 0.10-0.60. Several parameterisations of F2gamma are in qualitative agreement with the measurements whereas the quark-parton model prediction fails to describe the data.

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The OPAL collaboration, G. Abbiendi. 2002-02-19. Measurement of the Hadronic Photon Structure Function F2gamma at LEP2. https://arxiv.org/abs/hep-ex/0202035

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