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arXiv · 1107.3149

Z\gamma\gamma production with leptonic decays and triple photon production at NLO QCD

G. Bozzi·F. Campanario·M. Rauch·D. Zeppenfeld
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Abstract

We present a calculation of the O(alpha_s) QCD corrections to the production of a Z boson in association with two photons and to triple photon production at hadron colliders. All final-state photons are taken as real. For the Z boson, we consider the decays both into charged leptons and into neutrinos including all off-shell effects. Numerical results are obtained via a Monte Carlo program based on the structure of the VBFNLO program package. This allows us to implement general cuts and distributions of the final-state particles. We find that the NLO QCD corrections are sizable and significantly exceed the expectations from a scale variation of the leading-order result. In addition, differential distributions of important observables change considerably. The prediction of two-photon-associated Z production with Z decays into neutrinos from the charged-lepton rate works well, once we use an additional cut on the invariant mass of the charged-lepton pair.

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G. Bozzi, F. Campanario, M. Rauch, D. Zeppenfeld. 2011-07-15. Z\gamma\gamma production with leptonic decays and triple photon production at NLO QCD. https://doi.org/10.1103/physrevd.84.074028

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