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BABAR Collaboration(del Amo Sanchez, P. et al), Lopez-March, N., Martinez-Vidal, F., Milanes, D. A., & Oyanguren, A. (2010). Evidence for Direct CP Violation in the Measurement of the Cabbibo-Kobayashi-Maskawa Angle gamma with B-/+ -> D-(*K-)(()*()-/+) Decays. Phys. Rev. Lett., 105(12), 121801–7pp.
Abstract: We report the measurement of the Cabibbo-Kobayashi-Maskawa CP-violating angle gamma through a Dalitz plot analysis of neutral D-meson decays to K-S(0)pi(+) pi(-) and K-S(0) K+ K- produced in the processes B--/+ -> DK -/+, B--/+ -> D* K--/+ with D* -> D pi(0), D gamma and B -/+ DK*-/+ with K*(-/+) -> K-S(0)pi(-/+), using 468 million B (B) over bar pairs collected by the BABAR detector at the PEP-II asymmetric-energy e(+)e(-) collider at SLAC. We measure gamma = (68 +/- 14 +/- 4 +/- 3)degrees (modulo 180 degrees), where the first error is statistical, the second is the experimental systematic uncertainty, and the third reflects the uncertainty in the description of the neutral D decay amplitudes. This result is inconsistent with gamma = 0 ( no direct CP violation) with a significance of 3.5 standard deviations.
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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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