Estimation of SM backgrounds to SUSY search in the 1-lepton + jets + MET channel

TL;DR

This paper details the methods used by the ATLAS Collaboration to estimate key Standard Model backgrounds, such as ttbar, W+jets, and QCD, in SUSY searches involving one lepton, jets, and missing transverse energy.

Contribution

It introduces a combined approach using control regions and matrix methods for accurate background estimation in SUSY searches.

Findings

Reliable background estimates improve SUSY search sensitivity.

Control region extrapolation effectively predicts ttbar and W+jets backgrounds.

Matrix method provides robust QCD background estimation.

Abstract

The ATLAS Collaboration has reported the first results of the search for SUSY particles in 1-lepton + 3 jets + MET final states. An essential ingredient for these results is a reliable background estimation in the signal region, in particular of the ttbar, W+jets and QCD backgrounds. The estimation of these three backgrounds is explained in this paper. The ttbar and W+jets backgrounds are obtained from a background dominated control region and extrapolated to the signal region, whereas for the estimation of the QCD background a matrix method is used.