NLO QCD plus EW predictions for 2l2v diboson signatures at the LHC

作者：Kallweit S^*; Lindert J M; Pozzorini S; Schonherr M

来源：The Journal of High Energy Physics, 2017, 2017(11): 120.

DOI：10.1007/JHEP11(2017)120

• NLO Computations

We present next-to-leading order (NLO) calculations including QCD and electroweak (EW) corrections for 2l2v diboson signatures with two opposite-charge leptons and two neutrinos. Specifically, we study the processes pp -> e(+)mu(-) v(e) (v) over bar (mu) and pp -> e(+) e(-) v (v) over bar, including all relevant off-shell diboson channels, W+ W-, ZZ, gamma Z, 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 alpha for processes with initial-and final-state photons. All calculations are performed within the automated Munich/Sherpa+ Open Loops frameworks, and we provide numerical predictions for the LHC at 13TeV. 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 WW and ZZ contributions to the same-flavour channel, pp -> e(+) e(-) v (v) over bar, 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.

• 出版日期2017-11-20