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Consequences of t-channel unitarity for the interaction of real and virtual photons at high energies

E. Martynov·J. R. Cudell·G. Soyez
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Abstract

We analyze the consequences of t-channel unitarity for photon cross sections and show what assumptions are necessary to allow for the existence of new singularities at $ Q^{2}=0 $ for the $ γp $ and $ γγ$ total cross sections. For virtual photons, such singularities can in general be present, but we show that, apart from the perturbative singularity associated with $ γ^{*}γ^{*}\to q\bar q $, no new ingredient is needed to reproduce the data from LEP and HERA, in the Regge region.

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E. Martynov, J. R. Cudell, G. Soyez. 2002-11-28. Consequences of t-channel unitarity for the interaction of real and virtual photons at high energies. https://arxiv.org/abs/hep-ph/0211448

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