Evidence for electroweak production of four charged leptons and two jets in proton-proton collisions at s=13TeV

Abstract

Evidence is presented for the electroweak (EW) production of two jets (jj) in association with two Z bosons and constraints on anomalous quartic gauge couplings are set. The analysis is based on a data sample of proton-proton collisions at s=13TeV collected with the CMS detector in 2016–2018, and corresponding to an integrated luminosity of 137fb?1. The search is performed in the fully leptonic final state ZZ???????, where ?,??=e,?. The EW production of two jets in association with two Z bosons is measured with an observed (expected) significance of 4.0 (3.5) standard deviations. The cross sections for the EW production are measured in three fiducial volumes and the result is ?<inf>EW</inf>(pp?ZZjj???????jj)=0.33<inf>?0.10</inf> +0.11(stat)<inf>?0.03</inf> +0.04(syst)fb in the most inclusive volume, in agreement with the standard model prediction of 0.275±0.021fb. Measurements of total cross sections for jj production in association with two Z bosons are also reported. Limits on anomalous quartic gauge couplings are derived in terms of the effective field theory operators T0, T1, T2, T8, and T9. © 2020 The Author(s)