Measurement of the top-quark mass using missing ET+jets events with secondary vertex b-tagging at CDF II
Physical Review D - Particles, Fields, Gravitation and Cosmology 75:11 (2007)
Abstract:
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.Search for new physics in lepton+photon+X events with 929pb-1 of pp̄ collisions at s=1.96TeV
Physical Review D - Particles, Fields, Gravitation and Cosmology 75:11 (2007)
Abstract:
We present results of a search at CDF in 929±56pb-1 of pp̄ collisions at 1.96 TeV for the anomalous production of events containing a high-transverse momentum charged lepton (ℓ, either e or μ) and photon (γ), accompanied by missing transverse energy (E T), and/or additional leptons and photons, and jets (X). We use the same selection criteria as in a previous CDF Run I search, but with an order-magnitude larger data set, a higher pp̄ collision energy, and the CDF II detector. We find 163 ℓγE T+X events, compared to an expectation of 150.6±13.0 events. We observe 74 ℓγ+X events, compared to an expectation of 65.1±7.7 events. We find no events similar to the Run I eeγγE T event. © 2007 The American Physical Society.First measurement of the ratio of central-electron to forward-electron W partial cross sections in pp[over] collisions at (square root)s =1.96 TeV.
Phys Rev Lett 98:25 (2007) 251801
Abstract:
We present a measurement of sigma(pp[over] --> W) x B(W --> e nu) at (square root)s = 1.96 TeV, using electrons identified in the forward region (1.2 < |eta| < 2.8) of the CDF II detector, in 223 pb(-1) of data. We measure sigma x B = 2796 +/- 13(stat)(-90)(+95)(syst) +/- 162(lum) pb. Combining this result with a previous CDF measurement obtained using electrons in the central region (|eta| approximately < 1), we present the first measurement of the ratio of central-electron to forward-electron W partial cross sections R(exp) = 0.925 +/- 0.006(stat) +/- 0.032(syst), consistent with theoretical predictions using Coordinated Theoretical-Experimental Project on QCD (CTEQ) and Martin-Roberts-Stirling-Thorne (MRST) parton distribution functions.First measurement of the ratio of central-electron to forward-electron W partial cross sections in pp̄ collisions at s=1.96TeV
Physical Review Letters 98:25 (2007)
Abstract:
We present a measurement of σ(pp̄→W)×B(W→eν) at s=1.96TeV, using electrons identified in the forward region (1.2<|η|<2.8) of the CDF II detector, in 223pb-1 of data. We measure σ×B=2796±13(stat)-90+95(syst)±162(lum)pb. Combining this result with a previous CDF measurement obtained using electrons in the central region (|η| 1), we present the first measurement of the ratio of central-electron to forward-electron W partial cross sections Rexp=0.925±0.006(stat)±0.032(syst), consistent with theoretical predictions using Coordinated Theoretical-Experimental Project on QCD (CTEQ) and Martin-Roberts-Stirling-Thorne (MRST) parton distribution functions. © 2007 The American Physical Society.Measurement of sigma chi c2 B(chi c2-->J/psi gamma)/sigma chi c1 B(chi c1 -->J/psi gamma) in pp collisions at square root s=1.96 TeV.
Phys Rev Lett 98:23 (2007) 232001