Higher-order EW corrections in ZZ and ZZj production at the LHC

Abstract

We consider the production of a pair of Z bosons at the LHC and study the inclusion of EW corrections in theoretical predictions at fixed order and based on multijet-merged parton-shower simulations. To this end we present exact NLO EW results for pp → e⁺e⁻μ⁺μ⁻, and, for the first time, for pp → e⁺e⁻μ⁺μ⁻j, and compare them to the EW virtual and NLL Sudakov approximation. We then match the exact NLO EW result to the resummed Sudakov logarithms to achieve an improved $\mathrm{NLO}\mathrm{EW}+\mathrm{NLL}{\mathrm{EW}}_{\mathrm{sud}}^{\exp }$ result.

Further, we discuss the inclusion of the above EW corrections in MePs@Nlo event simulations in the framework of the Sherpa event generator. We present detailed phenomenological predictions for inclusive ZZ and ZZj production taking into account the dominant EW corrections through the EW virtual approximation, as well as through (exponentiated) EW Sudakov logarithms.