NLO QCD corrections to SM-EFT dilepton and electroweak Higgs boson production, matched to parton shower in POWHEG

TL;DR

This paper computes NLO QCD corrections to SM-EFT processes involving dilepton and Higgs production, integrating them with parton showering in POWHEG, to improve precision and sensitivity to new physics.

Contribution

It provides the first comprehensive NLO QCD calculations for multiple SM-EFT processes matched with parton shower in POWHEG, including all relevant dimension-six operators.

Findings

Differential distributions can distinguish between effective operators.

NLO corrections significantly impact the shape of key observables.

Constraints on operator coefficients are discussed with potential for experimental tests.

Abstract

We discuss the Standard Model Effective Field Theory (SM-EFT) contributions to neutral- and charge-current Drell-Yan production, associated production of the Higgs and a vector boson, and Higgs boson production via vector boson fusion. We consider all the dimension-six SM-EFT operators that contribute to these processes at leading order, include next-to-leading order QCD corrections, and interface them with parton showering and hadronization in Pythia8 according to the POWHEG method. We discuss existing constraints on the coefficients of dimension-six operators and identify differential and angular distributions that can differentiate between different effective operators, pointing to specific features of Beyond-the-Standard-Model physics.