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Prompt Photons in Photoproduction at HERA

Sung-Won Lee
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Abstract

First inclusive measurements of isolated prompt photons in photoproduction at HERA have been made with the ZEUS detector. Cross sections are given as a function of the pseudorapidity and the transverse energy of the photon, for E_T^gamma > 5 GeV in the gamma-p centre-of-mass energy range 134-285 GeV. Comparisons are made with predictions from LO Monte Carlo models and NLO QCD calculations. For forward eta^gamma (proton direction) good agreement is found, but in the rear direction all predictions fall below the data.

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Sung-Won Lee. 2000-08-06. Prompt Photons in Photoproduction at HERA. https://arxiv.org/abs/hep-ex/0008011

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