CDF Collaboration(Aaltonen, T. et al), & Cabrera, S. (2010). Measurement of the top quark mass and p(p)over-bar -> t(t)over-bar cross section in the all-hadronic mode with the CDF II detector. Phys. Rev. D, 81(5), 052011–20pp.
Abstract: We present a measurement of the top quark mass and of the top-antitop (t (t) over bar) pair production cross section using p (p) over bar data collected with the CDF II detector at the Tevatron Collider at the Fermi National Accelerator Laboratory and corresponding to an integrated luminosity of 2.9 fb(-1). We select events with six or more jets satisfying a number of kinematical requirements imposed by means of a neural-network algorithm. At least one of these jets must originate from a b quark, as identified by the reconstruction of a secondary vertex inside the jet. The mass measurement is based on a likelihood fit incorporating reconstructed mass distributions representative of signal and background, where the absolute jet energy scale ( JES) is measured simultaneously with the top quark mass. The measurement yields a value of 174.8 +/- 2.4(stat + JES)(-1.0)(+1.2)(syst) GeV/c(2), where the uncertainty from the absolute jet energy scale is evaluated together with the statistical uncertainty. The procedure also measures the amount of signal from which we derive a cross section, sigma(t (t$) over bar) = 7.2 +/- 0.5(stat) +/- 1.0(syst) +/- 0.4(lum) pb, for the measured values of top quark mass and JES.
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CDF Collaboration(Aaltonen, T. et al), Cabrera, S., & Cuenca Almenar, C. (2010). First Measurement of the b-Jet Cross Section in Events with a W Boson in p(p)over-bar Collisions at root s=1.96 TeV. Phys. Rev. Lett., 104(13), 131801–8pp.
Abstract: The cross section for jets from b quarks produced with a W boson has been measured in p (p) over bar collision data from 1: 9 fb(-1) of integrated luminosity recorded by the CDF II detector at the Tevatron. The W + b-jets process poses a significant background in measurements of top quark production and prominent searches for the Higgs boson. We measure a b-jet cross section of 2.74 + 0.27(stat) +/- 0.42(syst) pb in association with a single flavor of leptonic W boson decay over a limited kinematic phase space. This measured result cannot be accommodated in several available theoretical predictions.
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CDF Collaboration(Aaltonen, T. et al), & Cabrera, S. (2010). Search for Technicolor Particles Produced in Association with a W Boson at CDF. Phys. Rev. Lett., 104(11), 111802–7pp.
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CDF Collaboration(Aaltonen, T. et al), & Cabrera, S. (2010). Measurement of the WW plus WZ Production Cross Section Using the lepton plus jets Final State at CDF II. Phys. Rev. Lett., 104(10), 101801–8pp.
Abstract: We report two complementary measurements of the WW + WZ cross section in the final state consisting of an electron or muon, missing transverse energy, and jets, performed using p (p) over bar collision data at root s = 1.96 TeV collected by the CDF II detector. The first method uses the dijet invariant mass distribution while the second more sensitive method uses matrix-element calculations. The result from the second method has a signal significance of 5.4 sigma and is the first observation of WW + WZ production using this signature. Combining the results gives sigma(WW+WZ) = 16.0 +/- 3.3 pb, in agreement with the standard model prediction.
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CDF Collaboration(Aaltonen, T. et al), & Cabrera, S. (2010). Measurement of the Lambda(0)(b) Lifetime in Lambda(0)(b) -> Lambda(+)(c)pi(-) Decays in p(p)over-bar Collisions at root s=1.96 TeV. Phys. Rev. Lett., 104(10), 102002–8pp.
Abstract: We report a measurement of the lifetime of the Lambda(0)(b) baryon in decays to the Lambda(+)(c)pi(-) final state in a sample corresponding to 1.1 fb(-1) collected in p (p) over bar collisions at root s = 1.96 TeV by the CDF II detector at the Tevatron collider. Using a sample of about 3000 fully reconstructed Lambda(0)(b) events we measure tau(Lambda(0)(b) ) = 1.401 +/- 0.046(stat) +/- 0.035(syst) ps (corresponding to c tau(Lambda(0)(b)) = 420.1 +/- 13.7(stat) +/- 10.6(syst) μm, where c is the speed of light). The ratio of this result and the world average B-0 lifetime yields tau(Lambda(0)(b))/tau(B-0) = 0.918 +/- 0.038 (stat) and (syst), in good agreement with recent theoretical predictions.
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