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Register a new user$ZZ$ production at the LHC: NLO QCD corrections to the loop-induced gluon fusion channel
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Massimiliano Grazzini
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We consider QCD radiative corrections to the production of four charged leptons in hadron collisions. We present the computation of the next-to-leading order QCD corrections to the loop-induced gluon fusion contribution. Our predictions include, for the first time, also the quark-gluon partonic channels. The computed corrections, which are formally of ${cal O}(alpha_{rm s}^3)$, turn out to increase the loop-induced Born-level result by an amount ranging from 75% to 71% as $sqrt{s}$ ranges from 8 to 13 TeV. We combine our result with state-of-the-art NNLO corrections to the quark annihilation channel, and present updated predictions for fiducial cross sections and distributions for this process.
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