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Cross section of isolated prompt photons in hadron-hadron collisions

S. Catani·M. Fontannaz·J. Ph. Guillet·E. Pilon
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Abstract

We consider the production of isolated prompt photons in hadronic collisions. We present a general discussion in QCD perturbation theory of the isolation criterion used by hadron collider experiments. The isolation criterion is implemented in a computer programme of the Monte Carlo type, which evaluates the production cross section at next-to-leading order accuracy in perturbative QCD. The calculation includes both the direct and the fragmentation components of the cross section, without any approximation of the dependence on the radius R of the isolation cone. We examine the scale dependence of the isolated cross section, the sensitivity of the cross section to the values of the isolation parameters, and we provide a quantitative comparison between the full R dependence and its small-R approximation.

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S. Catani, M. Fontannaz, J. Ph. Guillet, E. Pilon. 2002-06-04. Cross section of isolated prompt photons in hadron-hadron collisions. https://doi.org/10.1088/1126-6708%2F2002%2F05%2F028

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