Measurement of the top-quark mass using missing ET+jets events with secondary vertex b-tagging at CDF II

We present a measurement of the top-quark mass in pp̄ collisions at s=1.96TeV which uses events with an inclusive signature of missing transverse energy and jets. The event selection is sensitive to tt̄→W+bW- b̄→lνbqq′b̄ independent of the lepton flavor and results in a large acceptance for W→τν decays. All-hadronic tt̄ decays and events with identified electrons or muons are vetoed to provide a statistically independent sample with respect to all previous measurements. The top-quark mass is inferred from the distribution of the scalar sum of all jet transverse energies and the missing transverse energy. Using 311pb-1 of integrated luminosity recorded by the Collider Detector at Fermilab, we measure a top-quark mass mt=172.3-9.6+10.8(stat)±10.8(syst)GeV/c2. While the uncertainty on mt is larger than that of other measurements, the result is statistically uncorrelated with those of other methods and thus can help to reduce the overall mt uncertainty when combined with other existing measurements. © 2007 The American Physical Society