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arXiv · hep-ph/9904277

Total $γ^*$ p Cross Section

E. Gotsman·E. Levin·U. Maor·E. Naftali
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Abstract

This paper shows that the approach based on Gribov's ideas for the photon-proton interaction, is able to describe the experimental data over a wide range of photon virtualities $Q^2 = 0 - 100 GeV^2$ and energies $\sqrt{s} = W = 3 - 300 GeV$. A simple model is suggested which provides a quantitative way of describing the matching between short and long distances (between "soft" and "hard" processes) in photon-proton interaction at high energy. The main results of our analysis are: (i) the values of the separation parameters differentiating the "soft" and "hard" interactions are determined; (ii) the additive quark model can be used to calculate the "soft" contribution to the photon - proton interaction; (iii) a good description of the ratio $σ_L/σ_T$ is obtained ; and (iv) a considerable contribution of the "soft" process at large $Q^2$, and of "hard" processes at small $Q^2$ was found.

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E. Gotsman, E. Levin, U. Maor, E. Naftali. 1999-04-08. Total $γ^*$ p Cross Section. https://doi.org/10.1007/s100520050607

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