Measurement of the $WW$ and $WZ$ production cross section using final states with a charged lepton and heavy-flavor jets in the full CDF Run II data set

TL;DR

This paper reports the measurement of WW and WZ production cross sections in proton-antiproton collisions at 1.96 TeV using the full CDF Run II dataset, providing evidence consistent with Standard Model predictions.

Contribution

First measurement of WW and WZ cross sections in heavy-flavor jet final states at the Tevatron with full dataset, including separate measurements for each process.

Findings

Total WW+WZ cross section measured as 13.7±3.9 pb.

Independent evidence for WW and WZ production with significances of 2.9σ and 2.1σ.

Results are consistent with Standard Model predictions.

Abstract

We present a measurement of the total {\it WW} and {\it WZ} production cross sections in $p\bar{p}$ collision at $\sqrt{s}=1.96$ TeV, in a final state consistent with leptonic $W$ boson decay and jets originating from heavy-flavor quarks from either a $W$ or a $Z$ boson decay. This analysis uses the full data set collected with the CDF II detector during Run II of the Tevatron collider, corresponding to an integrated luminosity of 9.4 fb$^{-1}$. An analysis of the dijet mass spectrum provides $3.7\sigma$ evidence of the summed production processes of either {\it WW} or {\it WZ} bosons with a measured total cross section of $\sigma_{WW+WZ} = 13.7\pm 3.9$~pb. Independent measurements of the {\it WW} and {\it WZ} production cross sections are allowed by the different heavy-flavor decay-patterns of the $W$ and $Z$ bosons and by the analysis of secondary-decay vertices reconstructed within heavy-flavor jets. The productions of {\it WW} and of {\it WZ} dibosons are independently seen with significances of $2.9\sigma$ and $2.1\sigma$, respectively, with total cross sections of $\sigma_{WW}= 9.4\pm 4.2$~pb and $\sigma_{WZ}=3.7^{+2.5}_{-2.2}$~pb. The measurements are consistent with standard-model predictions.