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arXiv · hep-ph/9306287

Direct vs. resolved photon: an exercise in factorization

J. Chýla
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Abstract

Direct and resolved photon interactions are shown to be intimately related through the factorization mechanism. It is argued that in theoretically consistent analysis of jet production in $γ$p and ep collisions the LO resolved $γ$ contribution must be considered together with the NLO direct $γ$ component. Recent data from HERA therefore do not provide a direct evidence for the former component, but should rather be interpreted as a manifestation of the $O(αα_s^2)$ term in $γ$p and, via the Weizsäcker-Williams approximation, in ep interactions.

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J. Chýla. 1993-06-18. Direct vs. resolved photon: an exercise in factorization. https://doi.org/10.1016/0370-2693(94)90844-3

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