Top Pair Production Cross-Section Measurement in the All-Hadronic Channel at CDF and Dzero

TL;DR

This paper reports measurements of the top-antitop quark pair production cross-section in the all-hadronic decay channel at the Fermilab Tevatron collider, using data from the CDF and Dzero experiments with advanced b-jet tagging techniques.

Contribution

It presents the first combined measurement of the ttbar cross-section in the all-hadronic channel at Tevatron energies using novel analysis methods for background suppression.

Findings

CDF measures σ_ttbar = 7.8 ± 2.5 (stat) +4.7/-2.3 (syst) pb.

Dzero measures σ_ttbar = 7.7 +3.4/-3.3 (stat) +4.7/-3.8 (syst) ± 0.5 (lumi) pb.

Both results are consistent with Standard Model predictions.

Abstract

Measurements of the ttbar production cross-section at \sqrt{s} = 1.96TeV in proton-antiproton collisions were performed by the CDF and Dzero collaborations using ttbar final states where both W's decay hadronically. Each experiment uses luminosity of about 160pb^-1 of data collected during Run II of the Fermilab Tevatron collider. Beside kinematical observables both experiments take advantage of identifying b-jets based on lifetime tagging. While CDF counts the number of b-tags over background after a cut based analysis, Dzero counts the excess of events after a neural network based kinematical selection and requiring a b-tagged jet. CDF obtains $\sigma_{ttbar}=7.8+-2.5{stat}^{+4.7}_{-2.3}{syst}; Dzero $\sigma_{ttbar}=7.7^{+3.4}_{-3.3}{stat}^{+4.7}_{-3.8}{syst}+-0.5{lumi}.