Matching Squark Pair Production at NLO with Parton Showers

TL;DR

This paper provides a detailed NLO calculation of squark pair production at the LHC, incorporating parton shower matching to improve the accuracy of supersymmetry searches.

Contribution

It introduces a fully differential NLO SUSY-QCD calculation for squark pair production with parton shower matching using the Powheg method, implemented in the Powheg-Box framework.

Findings

Reduced scale dependence in predictions

Significant K-factor variations observed

Parton showers impact differential distributions

Abstract

The pair production of squarks is one of the main search channels for supersymmetry at the LHC. We present a fully differential calculation of the next-to-leading order (NLO) SUSY-QCD corrections to the on-shell production of a pair of squarks in the Minimal Supersymmetric Standard Model (MSSM), supplemented by the leading-order decay of the squarks to the lightest neutralino and a quark. In addition, we use the Powheg method to match our NLO calculation with parton showers. To this end, the process was implemented in the Powheg-Box framework and interfaced with Pythia6 and Herwig++. We study the differential scale dependence and K-factors, and investigate the effects of the parton showers for a benchmark scenario in the constrained MSSM.