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On the non-perturbative part of the photon structure function

Gerhard A. Schuler
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Abstract

We discuss a dispersion relation in the photon mass and show how (in principle) model-independent constraints on the parton distribution functions of the photon, notably a momentum sumrule, can be obtained. We present two sets of parametrizations, SaS~1 and~2, corresponding to two rather extreme realizations of the non-perturbative part. Inclusive electron scattering off a real photon is found to be insufficient to constrain the non-perturbative components. The additional sensitivity provided by the photon virtuality is outlined. Previous approaches to model the non-perturbative input distributions are commented upon.

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Gerhard A. Schuler. 1995-06-09. On the non-perturbative part of the photon structure function. https://arxiv.org/abs/hep-ph/9506279

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