NLO QCD+EW predictions for 2ℓ2ν diboson signatures at the LHC

Kallweit, S.; Lindert, J.M.; Pozzorini, S.; Schoenherr, M.

Abstract

We present next-to-leading order (NLO) calculations including QCD and electroweak (EW) corrections for 2ℓ2ν diboson signatures with two opposite-charge leptons and two neutrinos. Specifically, we study the processes pp→e+μ−νeν¯¯¯μpp→e+μ−νeν¯μ and pp→e+e−νν¯¯¯pp→e+e−νν¯ , including all relevant off-shell diboson channels, W+W−, ZZ, γZ, as well as non-resonant contributions. Photon-induced processes are computed at NLO EW, and we discuss subtle differences related to the definition and the renormalisation of the coupling α for processes with initial- and final-state photons. All calculations are performed within the automated Munich/Sherpa+OpenLoops frameworks, and we provide numerical predictions for the LHC at 13 TeV. The behaviour of the corrections is investigated with emphasis on the high-energy regime, where NLO EW effects can amount to tens of percent due to large Sudakov logarithms. The interplay between W W and ZZ contributions to the same-flavour channel, pp→e+e−νν¯¯¯pp→e+e−νν¯ , is discussed in detail, and a quantitative analysis of photon-induced contributions is presented. Finally, we consider approximations that account for all sources of large logarithms, at high and low energy, by combining virtual EW corrections with a YFS soft-photon resummation or a QED parton shower.

Citation

Kallweit, S., Lindert, J., Pozzorini, S., & Schoenherr, M. (2017). NLO QCD+EW predictions for 2ℓ2ν diboson signatures at the LHC. Journal of High Energy Physics, 2017(11), Article 120. https://doi.org/10.1007/jhep11%282017%29120

• Journal Article Type: Article
• Acceptance Date: Nov 11, 2017
• Online Publication Date: Nov 20, 2017
• Publication Date: Nov 20, 2017
• Deposit Date: Dec 13, 2017
• Publicly Available Date: Dec 13, 2017
• Journal: Journal of High Energy Physics
• Print ISSN: 1126-6708
• Publisher: Scuola Internazionale Superiore di Studi Avanzati (SISSA)
• Peer Reviewed: Peer Reviewed
• Volume: 2017
• Issue: 11
• Article Number: 120
• DOI: https://doi.org/10.1007/jhep11%282017%29120