NLO QCD+NLO EW corrections to diboson production matched to parton shower

Mauro Chiesa,Emanuele Re,Carlo Oleari

doi:10.1140/epjc/s10052-020-8419-3

Abstract

We present the matching of NLO QCD and NLO EW corrections to parton showers for vector-boson pair production at the LHC. We consider leptonic final states, including resonant and non-resonant diagrams, spin correlations and off-shell effects. Our results are obtained interfacing the Recola2-Collier one-loop provider with the POWHEG-BOX-RES framework. We discuss our implementation, we validate it at fixed order, and we show our final results matched to parton shower. A by-product of our work is also a general interface between Recola2-Collier and POWHEG-BOX-RES. This is the first time that EW and QCD corrections to diboson production are consistently matched to parton showers.

Highlights

For all the above reasons, it is essential to make accurate predictions for vector boson pair production processes
We present the matching of NLO QCD and NLO EW corrections to parton showers for vector-boson pair production at the LHC
We computed the NLO QCD + NLO EW corrections to diboson production at hadron colliders matched to a complete parton shower, where QCD and QED radiation is simulated

Summary

Introduction

For all the above reasons, it is essential to make accurate predictions for vector boson pair production processes. The loopinduced processes gg → W +W − and gg → Z Z contribute to the final state at the same order in αS as the NNLO corrections to the qqinitial state They have been computed at LO in Refs. In the context of all-order computations in QCD, the NNLL-accurate results for the transverse-momentum distribution of the leptonic final state arising from pp → V V production were obtained in Ref. We remind the reader that, at fixed-order, a description of mixed terms can be obtained via a factorized ansatz, i.e. multiplying differential NLO QCD cross sections by EW correction factors, as done, for instance, in Ref. We use the notation NLOQCD + NLOEW to denote the additive combination of the hard matrix elements (in the POWHEG Bfunction)

Details of the calculation

Cross-checks and validation

Conclusions