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F_2^gamma at low Q^2 and sigma_{γγ} at high energies

B. Badelek·J. Kwiecinski·A. Stasto
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Abstract

The parametrisation of the photon structure function in the low Q^2 region is formulated. It includes the VMD contribution and the QCD improved parton model component suitably extrapolated to the low Q^2 region. The parametrisation describes reasonably well existing experimental data on sigma_{γγ} for real photons and the low Q^2 data on sigma_{γ^* γ}. Predictions for sigma_{γγ} and for sigma_{γ^* γ} for energies which may be accesssible in future linear colliders are also given.

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B. Badelek, J. Kwiecinski, A. Stasto. 1999-03-03. F_2^gamma at low Q^2 and sigma_{γγ} at high energies. https://arxiv.org/abs/hep-ph/9903248

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