Measurement of the WW+WZ Production Cross Section Using a Matrix Element Technique in Lepton + Jets Events

TL;DR

This paper reports a measurement of the combined WW and WZ production cross section in lepton+jets events using matrix element techniques, confirming consistency with Standard Model predictions.

Contribution

It introduces a matrix element method to distinguish diboson signals from background in lepton+jets events, providing a precise cross section measurement.

Findings

Measured WW+WZ cross section: 17.4 ± 3.3 pb

Results agree with Standard Model predictions

Used matrix element calculations for signal-background separation

Abstract

We present a measurement of the $WW+WZ$ production cross section observed in a final state consisting of an identified electron or muon, two jets, and missing transverse energy. The measurement is carried out in a data sample corresponding to up to 4.6~fb$^{-1}$ of integrated luminosity at $\sqrt{s} = 1.96$ TeV collected by the CDF II detector. Matrix element calculations are used to separate the diboson signal from the large backgrounds. The $WW+WZ$ cross section is measured to be $17.4\pm3.3$~pb, in agreement with standard model predictions. A fit to the dijet invariant mass spectrum yields a compatible cross section measurement.