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arXiv · hep-ex/0402019

Observation of isolated high-E_T photons in deep inelastic scattering

ZEUS Collaboration
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Abstract

First measurements of cross sections for isolated prompt photon production in deep inelastic ep scattering have been made using the ZEUS detector at the HERA electron-proton collider using an integrated luminosity of 121 pb^-1. A signal for isolated photons in the transverse energy and rapidity ranges 5 < E_T^gamma < 10 GeV and -0.7 < eta^gamma < 0.9 was observed for virtualities of the exchanged photon of Q^2 > 35 GeV^2. Cross sections are presented for inclusive prompt photons and for those accompanied by a single jet in the range E_T^jet \geq 6 GeV and -1.5 \leq eta^jet < 1.8. Calculations at order alpha^3alpha_s describe the data reasonably well.

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ZEUS Collaboration. 2004-02-11. Observation of isolated high-E_T photons in deep inelastic scattering. https://doi.org/10.1016/j.physletb.2004.05.033

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