Triboson production in the SMEFT

TL;DR

This paper investigates triboson production at the LHC within the SMEFT framework, highlighting significant QCD corrections and the potential for enhanced sensitivity to new physics through combined Higgs and triboson data.

Contribution

It provides the first NLO QCD analysis of triboson production in SMEFT and assesses its potential for probing heavy new physics at the LHC.

Findings

QCD corrections are large and phase-space dependent.

Resonant Higgs contributions dominate sensitivity.

Combining Higgs and triboson data enhances new physics reach.

Abstract

We study the production of three electroweak gauge bosons at the LHC, in the effective field theory of the standard model, at dimension six and next-to-leading order in QCD. We present results for inclusive cross-sections and differential distributions, finding that these QCD corrections are large, often vary across the phase-space and notably differ from those observed in the standard model. We then explore the potential of the recently observed triboson production processes for improving the sensitivity brought by electroweak precision observables and diboson data. The additional sensitivity we observe is dominated by resonant Higgs boson contributions, with decays to photon pairs in particular. A global analysis including Higgs boson data is therefore needed for a fair assessment of the future reach of triboson measurements on heavy new physics.