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*→ qq, no new ingredient is needed to reproduce the data from LEP and HERA, in the Regge region.
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Martynov, E., Cudell, J.R., Soyez, G. (2003). Consequences of T-Channel Unitarity for the Interaction of Real and Virtual Photons at High Energies. In: Fiore, R., Jenkovszky, L.L., Kotsky, M.I., Magas, V.K., Papa, A. (eds) DIFFRACTION 2002: Interpretation of the New Diffractive Phenomena in Quantum Chromodynamics and in the S-Matrix Theory. NATO Science Series, vol 101. Springer, Dordrecht. https://doi.org/10.1007/978-94-010-0177-9_7
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DOI: https://doi.org/10.1007/978-94-010-0177-9_7
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