BABAR Collaboration(del Amo Sanchez, P. et al), Lopez-March, N., Martinez-Vidal, F., Milanes, D. A., & Oyanguren, A. (2010). Observation of the Y(1(3)D(J)) bottomonium state through decays to pi(+)pi Y-(1S). Phys. Rev. D, 82(11), 111102–7pp.
Abstract: Based on 122 X 10(6)Y(3S) events collected with the BABAR detector, we have observed the Y(1(3)D(J)) bottomonium state through the Y(3S) -> gamma gamma Y(1(3)D(J)) -> gamma gamma pi(+)pi Y-(1S) decay chain. The significance for the J = 2 member of the Y(1(3)D(J)) triplet is 5.8 standard deviations including systematic uncertainties. The mass of the J = 2 state is determined to be 10 164.5 +/- 0.8(stat) +/- 0.5(syst) MeV/c(2). We use the pi(+)pi(-) invariant mass distribution to confirm the consistency of the observed state with the orbital angular momentum assignment of the Y(1(3)D(J)).
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CDF Collaboration(Aaltonen, T. et al), & Cabrera, S. (2010). Search for the Higgs Boson Using Neural Networks in Events with Missing Energy and b-Quark Jets in p(p)over-bar Collisions at root s=1.96 TeV. Phys. Rev. Lett., 104(14), 141801–7pp.
Abstract: We report on a search for the standard model Higgs boson produced in association with a W or Z boson in p (p) over bar collisions at root s = 1.96 TeV recorded by the CDF II experiment at the Tevatron in a data sample corresponding to an integrated luminosity of 2.1 fb(-1). We consider events which have no identified charged leptons, an imbalance in transverse momentum, and two or three jets where at least one jet is consistent with originating from the decay of a b hadron. We find good agreement between data and background predictions. We place 95% confidence level upper limits on the production cross section for several Higgs boson masses ranging from 110 GeV/c(2) to 150 GeV/c(2). For a mass of 115 GeV/c(2) the observed (expected) limit is 6.9 (5.6) times the standard model prediction.
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CDF Collaboration(Aaltonen, T. et al), & Cabrera, S. (2010). Study of the associated production of photons and b-quark jets in p(p)over-bar collisions at root s=1.96 TeV. Phys. Rev. D, 81(5), 052006–8pp.
Abstract: The cross section for photon production in association with at least one jet containing a b quark has been measured in proton antiproton collisions at root s = 1.96 TeV. The data sample used corresponds to an integrated luminosity of 340 pb(-1) collected with the CDF II detector. Both the differential cross section as a function of photon transverse energy E-T(gamma) and the total cross section are measured and compared to a next-to-leading order prediction for the process.
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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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