Combining QCD and electroweak corrections to dilepton production in FEWZ

TL;DR

This paper integrates NNLO QCD and NLO electroweak corrections into the FEWZ simulation code for dilepton production, enabling more precise theoretical predictions crucial for LHC measurements.

Contribution

It introduces a combined framework for NNLO QCD and NLO electroweak corrections in FEWZ, improving accuracy and consistency in dilepton production simulations.

Findings

Enhanced precision in dilepton production predictions at the LHC.

Analysis of photon radiation effects under experimental cuts.

Demonstration of combined corrections' impact on kinematic distributions.

Abstract

We combine the next-to-next-to-leading order (NNLO) QCD corrections to lepton-pair production through the Drell-Yan mechanism with the next-to-leading order (NLO) electroweak corrections within the framework of the FEWZ simulation code. Control over both sources of higher-order contributions is necessary for measurements where percent-level theoretical predictions are crucial, and in phase-space regions where the NLO electroweak corrections grow large. The inclusion of both corrections in a single simulation code eliminates the need to separately incorporate such effects as final-state radiation and electroweak Sudakov logarithms when comparing many experimental results to theory. We recalculate the NLO electroweak corrections in the complex-mass scheme for both massless and massive final-state leptons, and modify the QCD corrections in the original FEWZ code to maintain consistency with the complex-mass scheme to the lowest order. We present phenomenological results for LHC studies that include both NNLO QCD and NLO electroweak corrections. In addition, we study several interesting kinematics features induced by experimental cuts in the distribution of photon radiation at the LHC.