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arXiv · 2404.15113

Virtual QCD corrections to $gg \to ZZ$: top-quark loops from a transverse-momentum expansion

Giuseppe Degrassi·Ramona Gröber·Marco Vitti
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Abstract

We present the virtual corrections due to the top-quark loops for the process $gg \to ZZ$ at next-to-leading order in QCD. The associated two-loop box diagrams are computed using a small-transverse-momentum expansion. Our results are then merged with those available in the complementary energy region, obtained via a high-energy expansion, in order to provide an analytic result that is valid in the whole phase space. The results presented allow for an efficient modelling of the signal--background interference as well as the irreducible background in off-shell Higgs production.

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Giuseppe Degrassi, Ramona Gröber, Marco Vitti. 2024-04-23. Virtual QCD corrections to $gg \to ZZ$: top-quark loops from a transverse-momentum expansion. https://arxiv.org/abs/2404.15113

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