Simultaneous measurement of the ratio B(t->Wb)/B(t->Wq) and the top quark pair production cross section with the D0 detector at sqrt(s)=1.96 TeV

TL;DR

This paper reports the first simultaneous measurement of the top quark's decay ratio to Wb versus Wq and the top pair production cross section using D0 detector data, confirming standard model predictions.

Contribution

It introduces a method to measure both the decay ratio and production cross section simultaneously in the lepton plus jets channel with ppbar collision data.

Findings

Measured R = 0.97 +0.09-0.08, consistent with standard model.

Determined sigma_ttbar = 8.18 +0.90-0.84 pb, aligning with predictions.

Used event samples with varying numbers of identified b jets.

Abstract

We present the first simultaneous measurement of the ratio of branching fractions, R=B(t->Wb)/B(t->Wq), with q being a d, s, or b quark, and the top quark pair production cross section sigma_ttbar in the lepton plus jets channel using 0.9 fb-1 of ppbar collision data at sqrt(s)=1.96 TeV collected with the D0 detector. We extract R and sigma_ttbar by analyzing samples of events with 0, 1 and >= 2 identified b jets. We measure R = 0.97 +0.09-0.08 (stat+syst) and sigma_ttbar = 8.18 +0.90-0.84 (stat+syst)} +/-0.50 (lumi) pb, in agreement with the standard model prediction.