NLO electroweak and QCD corrections to the production of a photon with three charged lepton plus missing energy at the LHC

Abstract

Electroweak (EW) triboson production processes with at least one heavy gauge boson are of increasing interest at the Large Hadron Collider (LHC) as direct precision probes of one of the least-tested sectors of the Standard Model (SM), the quartic couplings of the EW gauge bosons. These processes therefore offer promising opportunities for searches for indirect signals of Beyond-the-SM (BSM) physics. In this paper, we present results for fiducial cross sections at next-to-leading-order (NLO) EW and NLO QCD to $pp\to e^{+}{\nu }_e{\mu }^{+}{\mu }^{-}\gamma$ at the 13 TeV LHC. This signature includes the triboson production process $pp\to W^{+}Z\gamma$ with leptonic decays, $W^{+}\to e^{+}{\nu }_e$ and $Z\to {\mu }^{+}{\mu }^{-}$. The computation is based on the complete set of leading-order (LO) contributions of $\mathcal{O}({\alpha }^5)$ and on NLO EW and NLO QCD cross sections of $\mathcal{O}({\alpha }^6)$ and $\mathcal{O}({\alpha }^5{\alpha }_{\text{s}})$, respectively, and thus off-shell effects, spin correlations and non-resonance contributions are fully taken into account. We construct a Monte Carlo framework which provides total and differential cross sections for a chosen set of basic analysis cuts. We find that while NLO EW corrections enhance the fiducial LO total cross section by only $1\%$, they can significantly change some distributions in certain kinematic regions. For example, the relative NLO EW corrections to the muon transverse momentum distribution at 500 GeV amounts to $-20\%$. To illustrate how missing NLO EW corrections could masquerade as BSM physics, we show examples for the impact of dimension-8 operators in the SM Effective Field Theory framework on selected kinematic distributions.

35 pages, 20 figures, 8 tables. V2: version to appear in PRD, references added and figures updated

References in corpus (23)

• The automated computation of tree-level and next-to-leading order differential cross sections, and their matching to parton shower simulations
• Event generation with SHERPA 1.1
• LHAPDF6: parton density access in the LHC precision era
• Automatic spin-entangled decays of heavy resonances in Monte Carlo simulations
• VBFNLO: A parton level Monte Carlo for processes with electroweak bosons
• OneLOop: for the evaluation of one-loop scalar functions
• GoSam-2.0: a tool for automated one-loop calculations within the Standard Model and beyond
• Scalar one-loop 4-point integrals
• The complex-mass scheme for perturbative calculations with unstable particles
• Automated one-loop computations in the SMEFT
• p p -> j j e+/- mu+/- nu nu and j j e+/- mu-/+ nu nu at O(α_{em}^6) and O(α_{em}^4 α_s^2) for the Study of the Quartic Electroweak Gauge Boson Vertex at LHC
• Automation of the Dipole Subtraction Method in MadGraph/MadEvent
• Polarized QED splittings of massive fermions and dipole subtraction for non-collinear-safe observables
• Evidence for electroweak production of four charged leptons and two jets in proton-proton collisions at $\sqrt{s}=$ 13 TeV
• A search for WW gamma and WZ gamma production and constraints on anomalous quartic gauge couplings in pp collisions at sqrt(s) = 8 TeV
• Study of $WW\gamma$ and $WZ\gamma$ production in $pp$ collisions at $\sqrt{s}=8$ TeV and search for anomalous quartic gauge couplings with the ATLAS experiment
• Photon Radiation with MadDipole
• Search for triboson $W^{\pm }{W}^{\pm }{W}^{\mp }$ production in $pp$ collisions at $\sqrt{s}=8$ TeV with the ATLAS detector
• Automated EW corrections with isolated photons: $t\bar{t}\gamma$, $t\bar{t}\gamma \gamma$ and $t\gamma j$ as case studies
• Measurement of the electroweak production of Z$\gamma$ and two jets in proton-proton collisions at $\sqrt{s}=$ 13 TeV and constraints on anomalous quartic gauge couplings
• NLO QCD + EW corrections to $ZZZ$ production with subsequent leptonic decays at LHC
• $WW\gamma$ production at hadron colliders with NLO QCD+EW corrections and parton shower effects
• $ZZ\gamma$ production in the NLO QCD+EW accuracy at the LHC

Cited by in corpus (4)

• Les Houches 2021: Physics at TeV Colliders: Report on the Standard Model Precision Wishlist
• Logarithmic EW corrections at one-loop
• Observation of $WZ\gamma$ Production in $pp$ Collisions at $\sqrt{s}=13$ TeV with the ATLAS Detector
• Les Houches 2023 -- Physics at TeV Colliders: Report on the Standard Model Precision Wishlist