Search

We present a measurement of the tt̄ production cross section in pp̄ collisions at s=1.96TeV using events containing a high transverse momentum electron or muon, three or more jets, and missing transverse energy. Events consistent with tt̄ decay are found by identifying jets containing candidate heavy-flavor semileptonic decays to muons. The measurement uses a CDF run II data sample corresponding to 2fb-1 of integrated luminosity. Based on 248 candidate events with three or more jets and an expected background of 79.5±5.3 events, we measure a production cross section of 9.1±1.6pb. © 2009 The American Physical Society.

We present a search for new particles in an extension to the standard model that includes a heavy Higgs boson (H0), a lighter charged Higgs boson (H ±), and an even lighter Higgs boson h0, with decays leading to a W-boson pair and a bottom-antibottom quark pair in the final state. We use events with exactly one lepton, missing transverse momentum, and at least four jets in data corresponding to an integrated luminosity of 8.7 fb-1 collected by the CDF II detector in proton-antiproton collisions at √s=1.96 TeV. We find the data to be consistent with standard model predictions and report the results in terms of a simplified Higgs-cascade-decay model, setting 95% confidence level upper limits on the product of cross section and branching fraction from 1.3 pb to 15 fb as a function of H0 and H ± masses for mh0=126 GeV/c2. © 2013 American Physical Society., This work was supported by the U.S. Department of Energy and National Science Foundation; the Italian Istituto Nazionale di Fisica Nucleare; the Ministry of Education, Culture, Sports, Science and Technology of Japan; the Natural Sciences and Engineering Research Council of Canada; the National Science Council of the Republic of China; the Swiss National Science Foundation; the A. P. Sloan Foundation; the Bundesministerium für Bildung und Forschung, Germany; the Korean World Class University Program, the National Research Foundation of Korea; the Science and Technology Facilities Council and the Royal Society, UK; the Russian Foundation for Basic Research; the Ministerio de Ciencia e Innovación, and Programa Consolider-Ingenio 2010, Spain; the Slovak R&D Agency; the Academy of Finland; and the Australian Research Council (ARC).

The lifetime of the B−c meson is measured using 272 exclusive B−c→J/ψ(→μ+μ−)π− decays reconstructed in data from proton-antiproton collisions corresponding to an integrated luminosity of 6.7 fb−1 recorded by the CDF II detector at the Fermilab Tevatron. The lifetime of the B−c meson is measured to be τ(B−c)=0.452±0.048(stat)±0.027(syst) ps. This is the first measurement of the B−c meson lifetime in a fully reconstructed hadronic channel, and it agrees with previous results and has comparable precision., This work was supported by the U.S. Department of Energy and National Science Foundation; the Italian Istituto Nazionale di Fisica Nucleare; the Ministry of Education, Culture, Sports, Science and Technology of Japan; the Natural Sciences and Engineering Research Council of Canada; the National Science Council of the Republic of China; the Swiss National Science Foundation; the A. P. Sloan Foundation; the Bundesministerium für Bildung und Forschung, Germany; the Korean World Class University Program; the National Research Foundation of Korea; the Science and Technology Facilities Council and the Royal Society, UK; the Russian Foundation for Basic Research; the Ministerio de Ciencia e Innovación, and Programa Consolider-Ingenio 2010, Spain; the Slovak R&D Agency; the Academy of Finland; and the Australian Research Council (ARC).

We present a search for the standard model Higgs boson produced in association with a Z boson in data collected with the CDF II detector at the Tevatron, corresponding to an integrated luminosity of 9.45fb -1. In events consistent with the decay of the Higgs boson to a bottom-quark pair and the Z boson to electron or muon pairs, we set 95% credibility level upper limits on the ZH production cross section times the H→bb̄ branching ratio as a function of Higgs boson mass. At a Higgs boson mass of 125GeV/c2, we observe (expect) a limit of 7.1 (3.9) times the standard model value. © 2012 American Physical Society., Department of Energy (US); National Science Foundation (US); Istituto Nazionale di Fisica Nucleare (Italia); Ministry of Education, Culture, Sports, Science and Technology (Japan); National Research Council of Canada; Swiss National Science Foundation; Alfred P. Sloan Foundation; Bundesministerium für Bildung und Forschung (Deutschland); National Research Foundation of Korea; Science and Technology Facilities Council (UK); The Royal Society (UK); Russian Foundation for Basic Research; Ministerio de Ciencia e Innovación (España); Slovak Research and Development Agency; Academy of Finland; Australian Research Council.

We report an indirect search for nonstandard model physics using the flavor-changing neutral current decays B -> K-(*)mu(+)mu(-). We reconstruct the decays and measure their angular distributions, as a function of q(2) = M(mu mu)(2)c(2), where M-mu mu is the dimuon mass, in p (P) over bar collisions at root s = 1.96 Tev using a data sample corresponding to an integrated luminosity of 6.8 fb(-1). The transverse polarization asymmetry A(T)((2)) and the time-reversal-odd charge-and-parity asymmetry A(im) are measured for the first time, together with the K* longitudinal polarization fraction F-L and the muon forward-backward asymmetry A(FB) for the decays B-0 -> K*(0)mu(+)mu(-) and B -> K*(+)mu(+)mu(-). The B -> K*mu(+)mu(-) forward-backward asymmetry in the most sensitive kinematic regime, 1, This work was supported by the U.S. Department of Energy and National Science Foundation; the Italian Istituto Nazionale di Fisica Nucleare; the Ministry of Education, Culture, Sports, Science and Technology of Japan; the Natural Sciences and Engineering Research Council of Canada; the National Science Council of the Republic of China; the Swiss National Science Foundation; the A. P. Sloan Foundation; the Bundesministerium fÜr Bildung und Forschung, Germany; the Korean World Class University Program, the National Research Foundation of Korea; the Science and Technology Facilities Council and the Royal Society, United Kingdom; the Russian Foundation for Basic Research; the Ministerio de Ciencia e Innovación, and Programa Consolider-Ingenio 2010, Spain; the Slovak R&D Agency; the Academy of Finland.

We present a search for the standard model Higgs boson produced in association with a W boson in √s=1.96TeV pp̄ collision data collected with the CDFA II detector at the Tevatron corresponding to an integrated luminosity of 9.45fb -1. In events consistent with the decay of the Higgs boson to a bottom-quark pair and the W boson to an electron or muon and a neutrino, we set 95% credibility level upper limits on the WH production cross section times the H→bb̄ branching ratio as a function of Higgs boson mass. At a Higgs boson mass of 125GeV/c2, we observe (expect) a limit of 4.9 (2.8) times the standard model value. © 2012 American Physical Society., Department of Energy (US); National Science Foundation (US); Istituto Nazionale di Fisica Nucleare (Italia); Ministry of Education, Culture, Sports, Science and Technology (Japan); National Research Council of Canada; Swiss National Science Foundation; Alfred P. Sloan Foundation; Bundesministerium für Bildung und Forschung (Deutschland); National Research Foundation of Korea; Science and Technology Facilities Council (UK); The Royal Society (UK); Russian Foundation for Basic Research; Ministerio de Ciencia e Innovación (España); Slovak Research and Development Agency; Academy of Finland; Australian Research Council.

We report an analysis of the Λb0→Λc+π -π +π - decay in a data sample collected by the CDF II detector at the Fermilab Tevatron corresponding to 2.4fb -1 of integrated luminosity. We reconstruct the currently largest samples of the decay modes Λb0→Λ c(2595) +π - (with Λ c(2595) +→Λc+π +π -), Λb0→Λ c(2625) +π - (with Λ c(2625) +→Λc+π +π -), Λb0→Σ c(2455) ++π -π - (with Σ c(2455) ++→Λc+π +), and Λb0→Σ c(2455)0π +π - (with Σ c(2455)0→Λc+π -) and measure the branching fractions relative to the Λb0→Λc+π - branching fraction. We measure the ratio B(Λb0→Λc+π -π +π -)/B(Λb0→Λc+π -)=3.04±0.33(stat)-0.55+0.70(syst) which is used to derive B(Λb0→Λc+π -π +π -)= (26.8-11.2+11.9)×10 -3. © 2012 American Physical Society., This work was supported by the U.S. Department of Energy and National Science Foundation; the Italian Istituto Nazionale di Fisica Nucleare; the Ministry of Education, Culture, Sports, Science and Technology of Japan; the Natural Sciences and Engineering Research Council of Canada; the National Science Council of the Republic of China; the Swiss National Science Foundation; the A. P. Sloan Foundation; the Bundesministerium für Bildung und Forschung, Germany; the Korean World Class University Program, the National Research Foundation of Korea; the Science and Technology Facilities Council and the Royal Society, UK; the Russian Foundation for Basic Research; the Ministerio de Ciencia e Innovación, and Programa Consolider-Ingenio 2010, Spain; the Slovak R&D Agency; the Academy of Finland; and the Australian Research Council (ARC).

This article describes the current most precise measurement of the WZ production cross section as well as limits on anomalous WWZ couplings at a center-of-mass energy of 1.96 TeV in proton-antiproton collisions for the Collider Detector at Fermilab (CDF). WZ candidates are reconstructed from decays containing three charged leptons and missing energy from a neutrino, where the charged leptons are either electrons or muons. Using data collected by the CDF II detector (7.1fb -1 of integrated luminosity), 63 candidate events are observed with the expected background contributing 8±1 events. The measured total cross section σ(pp̄→WZ)=3.93-0.53+0.60(stat)-0. 46+0.59(syst)pb is in good agreement with the standard model prediction of 3.50±0.21. The same sample is used to set limits on anomalous WWZ couplings. © 2012 American Physical Society., This work was supported by the U.S. Department of Energy and National Science Foundation; the Italian Istituto Nazionale di Fisica Nucleare; the Ministry of Education, Culture, Sports, Science and Technology of Japan; the Natural Sciences and Engineering Research Council of Canada; the National Science Council of the Republic of China; the Swiss National Science Foundation; the A. P. Sloan Foundation; the Bundesministerium fÜr Bildung und Forschung, Germany; the Korean World Class University Program, the National Research Foundation of Korea; the Science and Technology Facilities Council and the Royal Society, United Kingdom; the Russian Foundation for Basic Research; the Ministerio de Ciencia e Innovación, and Programa Consolider-Ingenio 2010, Spain; the Slovak R&D Agency; the Academy of Finland; and the Australian Research Council (ARC).

We present a search for a new heavy vector boson Z′ that decays to gluons. Decays to on-shell gluons are suppressed, leading to a dominant decay mode of Z′→g*g. We study the case where the off-shell gluon g* converts to a pair of top quarks, leading to a final state of tt¯g. In a sample of events with exactly one charged lepton, large missing transverse momentum and at least five jets, corresponding to an integrated luminosity of 8.7 fb-1 collected by the CDF II detector, we find the data to be consistent with the standard model. We set upper limits on the production cross section times branching ratio of this chromophilic Z′ at 95% confidence level from 300 to 40 fb for Z′ masses ranging from 400 to 1000 GeV/c2, respectively., This work was supported by the U.S. Department of Energy and National Science Foundation; the Italian Istituto Nazionale di Fisica Nucleare; the Ministry of Education, Culture, Sports, Science and Technology of Japan; the Natural Sciences and Engineering Research Council of Canada; the National Science Council of the Republic of China; the Swiss National Science Foundation; the A. P. Sloan Foundation; the Bundesministerium für Bildung und Forschung, Germany; the Korean World Class University Program, the National Research Foundation of Korea; the Science and Technology Facilities Council and the Royal Society, UK; the Russian Foundation for Basic Research; the Ministerio de Ciencia e Innovación, and Programa Consolider-Ingenio 2010, Spain; the Slovak R&D Agency; the Academy of Finland; and the Australian Research Council (ARC).

We present a measurement of the CP-violating parameter βsJ/ψ using approximately 6500 Bs0→J/ψ decays reconstructed with the CDF II detector in a sample of pp̄ collisions at √s=1.96TeV corresponding to 5.2fb -1 integrated luminosity produced by the Tevatron collider at Fermilab. We find the CP-violating phase to be within the range βsJ/ψ [0.02,0.52] [1.08,1.55] at 68% confidence level where the coverage property of the quoted interval is guaranteed using a frequentist statistical analysis. This result is in agreement with the standard model expectation at the level of about one Gaussian standard deviation. We consider the inclusion of a potential S-wave contribution to the Bs0→J/ψK +K - final state which is found to be negligible over the mass interval 1.009, This work was supported by the U.S. Department of Energy and National Science Foundation; the Italian Istituto Nazionale di Fisica Nucleare; the Ministry of Education, Culture, Sports, Science and Technology of Japan; the Natural Sciences and Engineering Research Council of Canada; the National Science Council of the Republic of China; the Swiss National Science Foundation; the A. P. Sloan Foundation; the Bundesministerium für Bildung und Forschung, Germany; the Korean World Class University Program, the National Research Foundation of Korea; the Science and Technology Facilities Council and the Royal Society, UK; the Russian Foundation for Basic Research; the Ministerio de Ciencia e Innovación, and Programa Consolider-Ingenio 2010, Spain; the Slovak R&D Agency; the Academy of Finland; and the Australian Research Council (ARC).

This paper presents a search for anomalous production of multiple low-energy leptons in association with a W or Z boson using events collected at the CDF experiment corresponding to 5.1fb -1 of integrated luminosity. This search is sensitive to a wide range of topologies with low-momentum leptons, including those with the leptons near one another. The observed rates of production of additional electrons and muons are compared with the standard model predictions. No indications of phenomena beyond the standard model are found. A 95% confidence level limit is presented on the production cross section for a benchmark model of supersymmetric hidden-valley Higgs production. Particle identification efficiencies are also provided to enable the calculation of limits on additional models. © 2012 American Physical Society., This work was supported by the U.S. Department of Energy and National Science Foundation; the Italian Istituto Nazionale di Fisica Nucleare; the Ministry of Education, Culture, Sports, Science and Technology of Japan; the Natural Sciences and Engineering Research Council of Canada; the National Science Council of the Republic of China; the Swiss National Science Foundation; the A. P. Sloan Foundation; the Bundesministerium für Bildung und Forschung, Germany; the World Class University Program, the National Research Foundation of Korea; the Science and Technology Facilities Council and the Royal Society, UK; the Institut National de Physique Nucleaire et Physique des Particules/CNRS; the Russian Foundation for Basic Research; the Ministerio de Ciencia e Innovación, and Programa Consolider-Ingenio 2010, Spain; the Slovak R&DAgency; and the Academy of Finland.

We search for high-mass resonances decaying into Z boson pairs using data corresponding to 6 fb-1 collected by the CDF experiment in pp¯ collisions at s=1.96 TeV. The search is performed in three distinct final states: ZZ→ℓ+ℓ-ℓ+ℓ-, ZZ→ℓ+ℓ-νν, and ZZ→ℓ+ℓ-jj. For a Randall-Sundrum graviton G*, the 95% CL upper limits on the production cross section times branching ratio to ZZ, σ(pp¯→G*→ZZ), vary between 0.26 pb and 0.045 pb in the mass range 300, Department of Energy (US); National Science Foundation (US); Istituto Nazionale di Fisica Nucleare (Italia); Ministry of Education, Culture, Sports, Science and Technology (Japan); National Research Council of Canada; Swiss National Science Foundation; Alfred P. Sloan Foundation; Bundesministerium für Bildung und Forschung (Deutschland); National Research Foundation of Korea; Science and Technology Facilities Council (UK); The Royal Society (UK); Russian Foundation for Basic Research; Ministerio de Ciencia e Innovación (España); Slovak Research and Development Agency; Academy of Finland; Australian Research Council

We report a measurement of time-integrated CP-violation asymmetries in the resonant substructure of the three-body decay D0→KS0π +π - using CDF II data corresponding to 6.0fb -1 of integrated luminosity from Tevatron pp̄ collisions at √s=1.96TeV. The charm mesons used in this analysis come from D *+(2010) →D0π + and D *-(2010)→D ̄0π -, where the production flavor of the charm meson is determined by the charge of the accompanying pion. We apply a Dalitz-amplitude analysis for the description of the dynamic decay structure and use two complementary approaches, namely, a full Dalitz-plot fit employing the isobar model for the contributing resonances and a model-independent bin-by-bin comparison of the D0 and D ̄0 Dalitz plots. We find no CP-violation effects and measure an asymmetry of A CP=(-0.05±0. 57(stat)±0.54(syst))% for the overall integrated CP-violation asymmetry, consistent with the standard model prediction. © 2012 American Physical Society., This work was supported by the U.S. Department of Energy and National Science Foundation; the Italian Istituto Nazionale di Fisica Nucleare; the Ministry of Education, Culture, Sports, Science and Technology of Japan; the Natural Sciences and Engineering Research Council of Canada; the National Science Council of the Republic of China; the Swiss National Science Foundation; the A. P. Sloan Foundation; the Bundesministerium für Bildung und Forschung, Germany; the Korean World Class University Program, the National Research Foundation of Korea; the Science and Technology Facilities Council and the Royal Society, United Kingdom; the Russian Foundation for Basic Research; the Ministerio de Ciencia e Innovación, and Programa Consolider-Ingenio 2010, Spain; the Slovak R&D Agency; the Academy of Finland; and the Australian Research Council (ARC).

We present a search for new phenomena in events with two reconstructed Z bosons and large missing transverse momentum, sensitive to processes pp̅ →X2X2→ZZX1X1, where X2 is an unstable particle decaying as X2→ZX1 and X1 is undetected. The particles X1 and X2 may be, among other possibilities, fourth-generation neutrinos or supersymmetric particles. We study the final state in which one Z boson decays to two charged leptons and the second decays hadronically. In data corresponding to an integrated luminosity of 4.2 fb-1 from proton-antiproton collisions recorded by the CDF II detector at the Tevatron, with center-of-mass energy of 1.96 TeV, we find agreement between data and standard-model backgrounds. We calculate 95% confidence level upper limits on the cross section of the process pp̅ →X2X2→ZZX1X1 ranging from 50 fb to 1 pb, depending on the masses of X1 and X2., Department of Energy (US); National Science Foundation (US); Istituto Nazionale di Fisica Nucleare (Italia); Ministry of Education, Culture, Sports, Science and Technology (Japan); National Research Council of Canada; Swiss National Science Foundation; Alfred P. Sloan Foundation; Bundesministerium für Bildung und Forschung (Deutschland); National Research Foundation of Korea; Science and Technology Facilities Council (UK); The Royal Society (UK); Russian Foundation for Basic Research; Ministerio de Ciencia e Innovación (España); Slovak Research and Development Agency; Academy of Finland.

The transverse momentum cross section of e+ e- pairs in the Z-boson mass region of 66-116 GeV/c2 is precisely measured using Run II data corresponding to 2.1fb -1 of integrated luminosity recorded by the Collider Detector at Fermilab. The cross section is compared with two quantum chromodynamic calculations. One is a fixed-order perturbative calculation at O(αs2), and the other combines perturbative predictions at high transverse momentum with the gluon resummation formalism at low transverse momentum. Comparisons of the measurement with calculations show reasonable agreement. The measurement is of sufficient precision to allow refinements in the understanding of the transverse momentum distribution. © 2012 American Physical Society., Department of Energy (US); National Science Foundation (US); Istituto Nazionale di Fisica Nucleare (Italia); Ministry of Education, Culture, Sports, Science and Technology (Japan); National Research Council of Canada; Swiss National Science Foundation; Alfred P. Sloan Foundation; Bundesministerium für Bildung und Forschung (Deutschland); National Research Foundation of Korea; Science and Technology Facilities Council (UK); The Royal Society (UK); Russian Foundation for Basic Research; Ministerio de Ciencia e Innovación (España); Slovak Research and Development Agency; Ministry of Science and Technology of the People's Republic of China; Academy of Finland; Australian Research Council.

In this Letter, we present a precise measurement of the total ZZ production cross section in pp̄ collisions at √s=1.96TeV, using data collected with the CDF II detector corresponding to an integrated luminosity of approximately 6fb -1. The result is obtained by combining separate measurements in the four-charged ( ′′) and two-charged-lepton and two-neutral-lepton (νν) decay modes of the Z boson pair. The combined measured cross section for pp̄→ZZ is 1.64-0.38+0.44pb. This is the most precise measurement of the ZZ production cross section in 1.96 TeV pp̄ collisions to date. © 2012 American Physical Society., This work was supported by the U.S. Department of Energy and National Science Foundation; the Italian Istituto Nazionale di Fisica Nucleare; the Ministry of Education, Culture, Sports, Science and Technology of Japan; the Natural Sciences and Engineering Research Council of Canada; the National Science Council of the Republic of China; the Swiss National Science Foundation; the A. P. Sloan Foundation; the Bundesministerium für Bildung und Forschung, Germany; the Korean World Class University Program, the National Research Foundation of Korea; the Science and Technology Facilities Council and the Royal Society, UK; the Russian Foundation for Basic Research; the Ministerio de Ciencia e Innovación, and Programa Consolider-Ingenio 2010, Spain; the Slovak R&D Agency; the Academy of Finland; and the Australian Research Council (ARC)., This work was supported by the U.S. Department of Energy and National Science Foundation; the Italian Istituto Nazionale di Fisica Nucleare; the Ministry of Education, Culture, Sports, Science and Technology of Japan; the Natural Sciences and Engineering Research Council of Canada; the National Science Council of the Republic of China; the Swiss National Science Foundation; the A. P. Sloan Foundation; the Bundesministerium fÜr Bildung und Forschung, Germany; the Korean World Class University Program, the National Research Foundation of Korea; the Science and Technology Facilities Council and the Royal Society, United Kingdom; the Russian Foundation for Basic Research; the Ministerio de Ciencia e Innovación, and Programa Consolider-Ingenio 2010, Spain; the Slovak R&D Agency; the Academy of Finland.

We present a search for the standard model Higgs boson produced in association with a W ± boson. This search uses data corresponding to an integrated luminosity of 7.5fb -1 collected by the CDF detector at the Tevatron. We select WH→νbb̄ candidate events with two jets, large missing transverse energy, and exactly one charged lepton. We further require that at least one jet be identified to originate from a bottom quark. Discrimination between the signal and the large background is achieved through the use of a Bayesian artificial neural network. The number of tagged events and their distributions are consistent with the standard model expectations. We observe no evidence for a Higgs boson signal and set 95% C.L. upper limits on the WH production cross section times the branching ratio to decay to bb̄ pairs, σ(pp̄→W ±H) ×B(H→bb̄), relative to the rate predicted by the standard model. For the Higgs boson mass range of 100 to 150GeV/c2 we set observed (expected) upper limits from 1.34 (1.83) to 38.8 (23.4). For 115GeV/c2 the upper limit is 3.64 (2.78). The combination of the present search with an independent analysis that selects events with three jets yields more stringent limits ranging from 1.12 (1.79) to 34.4 (21.6) in the same mass range. For 115 and 125GeV/c2 the upper limits are 2.65 (2.60) and 4.36 (3.69), respectively. © 2012 American Physical Society., Department of Energy (US); National Science Foundation (US); Istituto Nazionale di Fisica Nucleare (Italia); Ministry of Education, Culture, Sports, Science and Technology (Japan); National Research Council of Canada; Swiss National Science Foundation; Alfred P. Sloan Foundation; Bundesministerium für Bildung und Forschung (Deutschland); National Research Foundation of Korea; Science and Technology Facilities Council (UK); The Royal Society (UK); Russian Foundation for Basic Research; Ministerio de Ciencia e Innovación (España); Slovak Research and Development Agency; Academy of Finland; Australian Research Council.

We report on a search for the standard model Higgs boson produced in association with a vector boson in the full data set of proton-antiproton collisions at √s=1.96TeV recorded by the CDF II detector at the Tevatron, corresponding to an integrated luminosity of 9.45fb-1. We consider events having no identified charged lepton, a transverse energy imbalance, and two or three jets, of which at least one is consistent with originating from the decay of a b quark. We place 95% credibility level upper limits on the production cross section times standard model branching fraction for several mass hypotheses between 90 and 150GeV/c2. For a Higgs boson mass of 125GeV/c2, the observed (expected) limit is 6.7 (3.6) times the standard model prediction. © 2012 American Physical Society., Department of Energy (US); National Science Foundation (US); Istituto Nazionale di Fisica Nucleare (Italia); Ministry of Education, Culture, Sports, Science and Technology (Japan); National Research Council of Canada; Swiss National Science Foundation; Alfred P. Sloan Foundation; Bundesministerium für Bildung und Forschung (Deutschland); National Research Foundation of Korea; Science and Technology Facilities Council (UK); The Royal Society (UK); Russian Foundation for Basic Research; Ministerio de Ciencia e Innovación (España); Slovak Research and Development Agency; Academy of Finland; Australian Research Council.

29 páginas, 25 figuras, 14 tablas.-- CDF Collaboration: et al., This paper presents a search for standard model Higgs boson production in association with a W boson using events recorded by the CDF experiment in a data set corresponding to an integrated luminosity of 5.6 fb-1. The search is performed using a matrix element technique in which the signal and background hypotheses are used to create a powerful discriminator. The discriminant output distributions for signal and background are fit to the observed events using a binned likelihood approach to search for the Higgs boson signal. We find no evidence for a Higgs boson, and 95% confidence level (C.L.) upper limits are set on σ(pp̅ →WH)×B(H→bb̅ ). The observed limits range from 3.5 to 37.6 relative to the standard model expectation for Higgs boson masses between mH=100 GeV/c2 and mH=150 GeV/c2. The 95% C.L. expected limit is estimated from the median of an ensemble of simulated experiments and varies between 2.9 and 32.7 relative to the production rate predicted by the standard model over the Higgs boson mass range studied., Department of Energy (US); National Science Foundation (US); Istituto Nazionale di Fisica Nucleare (Italia); Ministry of Education, Culture, Sports, Science and Technology (Japan); National Research Council of Canada; Swiss National Science Foundation; Alfred P. Sloan Foundation; Bundesministerium für Bildung und Forschung (Deutschland); National Research Foundation of Korea; Science and Technology Facilities Council (UK); The Royal Society (UK); Russian Foundation for Basic Research; Ministerio de Ciencia e Innovación (España); Slovak Research and Development Agency; Academy of Finland; Australian Research Council.

We report a set of measurements of inclusive invariant pT differential cross sections of Λ0, Λ¯0, Ξ±, and Ω± hyperons reconstructed in the central region with pseudorapidity |η, This work was supported by the U.S. Department of Energy and National Science Foundation; the Italian Istituto Nazionale di Fisica Nucleare; the Ministry of Education, Culture, Sports, Science and Technology of Japan; the Natural Sciences and Engineering Research Council of Canada; the National Science Council of the Republic of China; the Swiss National Science Foundation; the A. P. Sloan Foundation; the Bundesministerium für Bildung und Forschung, Germany; the World Class University Program, the National Research Foundation of Korea; the Science and Technology Facilities Council and the Royal Society, UK; the Institut National de Physique Nucleaire et Physique des Particules/CNRS; the Russian Foundation for Basic Research; the Ministerio de Ciencia e Innovación, and Programa Consolider-Ingenio 2010, Spain; the Slovak R&DAgency; and the Academy of Finland.

We present the first direct measurement of the top-quark mass using tt¯ events decaying in the hadronic τ+jets decay channel. Using data corresponding to an integrated luminosity of 2.2 fb−1 collected by the CDF II detector in pp¯ collisions at s√=1.96 TeV at the Fermilab Tevatron, we measure the tt¯ cross section, σtt¯, and the top-quark mass, Mtop. We extract Mtop from a likelihood based on per-event probabilities calculated with leading-order signal and background matrix elements. We measure σtt¯=8.8±3.3(stat)±2.2(syst) pb and Mtop=172.7±9.3(stat)±3.7(syst) GeV/c2., This work was supported by the U.S. Department of Energy and National Science Foundation; the Italian Istituto Nazionale di Fisica Nucleare; the Ministry of Education, Culture, Sports, Science and Technology of Japan; the Natural Sciences and Engineering Research Council of Canada; the National Science Council of the Republic of China; the Swiss National Science Foundation; the A. P. Sloan Foundation; the Bundesministerium fÜr Bildung und Forschung, Germany; the Korean World Class University Program, the National Research Foundation of Korea; the Science and Technology Facilities Council and the Royal Society, United Kingdom; the Russian Foundation for Basic Research; the Ministerio de Ciencia e Innovación, and Programa Consolider-Ingenio 2010, Spain; the Slovak R&D Agency; the Academy of Finland; and the Australian Research Council (ARC).

We have observed exclusive γγ production in proton-antiproton collisions at √s=1.96 TeV, using data from 1.11±0.07 fb-1 integrated luminosity taken by the Run II Collider Detector at Fermilab. We selected events with two electromagnetic showers, each with transverse energy ET>2.5 GeV and pseudorapidity |η|2.5 GeV is 2.48-0.35+0.40(stat)-0.51+0.40(syst) pb., This work was supported by the U.S. Department of Energy and National Science Foundation; the Italian Istituto Nazionale di Fisica Nucleare; the Ministry of Education, Culture, Sports, Science and Technology of Japan; the Natural Sciences and Engineering Research Council of Canada; the National Science Council of the Republic of China; the Swiss National Science Foundation; the A. P. Sloan Foundation; the Bundesministerium für Bildung und Forschung, Germany; the Korean World Class University Program, the National Research Foundation of Korea; the Science and Technology Facilities Council and the Royal Society, UK; the Russian Foundation for Basic Research; the Ministerio de Ciencia e Innovación, and Programa Consolider-Ingenio 2010, Spain; the Slovak R&D Agency; the Academy of Finland; and the Australian Research Council (ARC).

We report on a measurement of CP-violating asymmetries (A CP) in the Cabibbo-suppressed D0→π +Ï€ - and D0→K +K - decays reconstructed in a data sample corresponding to 5.9fb -1 of integrated luminosity collected by the upgraded Collider Detector at Fermilab. We use the strong decay D *+→D0Ï€ + to identify the flavor of the charmed meson at production and exploit CP-conserving strong ccÌ„ pair production in ppÌ„ collisions. High-statistics samples of Cabibbo-favored D0→K -Ï€ + decays with and without a D *± tag are used to correct for instrumental effects and significantly reduce systematic uncertainties. We measure A CP(D0→π +Ï€ -)=(+0.22±0.24(stat) ±0.11(syst))% and A CP(D0→K +K -)=(-0.24±0.22(stat)±0.09(syst))%, in agreement with CP conservation. These are the most precise determinations from a single experiment to date. Under the assumption of negligible direct CP violation in D0→π +Ï€ - and D0→K +K - decays, the results provide an upper limit to the CP-violating asymmetry in D0 mixing, |ACPind(D0), This work was supported by the U.S. Department of Energy and National Science Foundation; the Italian Istituto Nazionale di Fisica Nucleare; the Ministry of Education, Culture, Sports, Science and Technology of Japan; the Natural Sciences and Engineering Research Council of Canada; the National Science Council of the Republic of China; the Swiss National Science Foundation; the A.P. Sloan Foundation; the Bundesministerium fü̈r Bildung und Forschung, Germany; the Korean World Class University Program, the National Research Foundation of Korea; the Science and Technology Facilities Council and the Royal Society, UK; the Russian Foundation for Basic Research; the Ministerio de Ciencia e Innovación, and Programa Consolider-Ingenio 2010, Spain; the Slovak R&D Agency; and the Academy of Finland.

A search for a narrow Higgs boson resonance in the diphoton mass spectrum is presented based on data corresponding to 7.0fb -1 of integrated luminosity from ppÌ„ collisions at √s=1.96TeV collected by the CDF experiment. No evidence of such a resonance is observed, and upper limits are set on the cross section times branching ratio of the resonant state as a function of Higgs boson mass. The limits are interpreted in the context of the standard model and one fermiophobic benchmark model where the data exclude fermiophobic Higgs bosons with masses below 114GeV/c2 at a 95% Bayesian credibility level. © 2012 American Physical Society., This work was supported by the U.S. Department of Energy and National Science Foundation; the Italian Istituto Nazionale di Fisica Nucleare; the Ministry of Education, Culture, Sports, Science and Technology of Japan; the Natural Sciences and Engineering Research Council of Canada; the National Science Council of the Republic of China; the Swiss National Science Foundation; the A. P. Sloan Foundation; the Bundesministerium für Bildung und Forschung, Germany; the Korean World Class University Program, the National Research Foundation of Korea; the Science and Technology Facilities Council and the Royal Society, UK; the Russian Foundation for Basic Research; the Ministerio de Ciencia e Innovación, and Programa Consolider-Ingenio 2010, Spain; the Slovak R&D Agency; the Academy of Finland; and the Australian Research Council (ARC).

We present the results of a search for dark matter production in the monojet signature. We analyze a sample of Tevatron pp̄ collisions at √s=1.96TeV corresponding to an integrated luminosity of 6.7fb -1 recorded by the CDF II detector. In events with large missing transverse energy and one energetic jet, we find good agreement between the standard model prediction and the observed data. We set 90% confidence level upper limits on the dark matter production rate. The limits are translated into bounds on nucleon-dark matter scattering rates which are competitive with current direct detection bounds on spin-independent interaction below a dark matter candidate mass of 5GeV/c2, and on spin-dependent interactions up to masses of 200GeV/c2. © 2012 American Physical Society., This work was supported by the U.S. Department of Energy and National Science Foundation; the Italian Istituto Nazionale di Fisica Nucleare; the Ministry of Education, Culture, Sports, Science and Technology of Japan; the Natural Sciences and Engineering Research Council of Canada; the National Science Council of the Republic of China; the Swiss National Science Foundation; the A. P. Sloan Foundation; the Bundesministerium für Bildung und Forschung, Germany; the Korean World Class University Program, the National Research Foundation of Korea; the Science and Technology Facilities Council and the Royal Society, UK; the Russian Foundation for Basic Research; the Ministerio de Ciencia e Innovación, and Programa Consolider-Ingenio 2010, Spain; the Slovak R&D Agency; the Academy of Finland; and the Australian Research Council (ARC).

We report on a study of diffractive dijet production in p̄p collisions at √s=1.96TeV using the CDF II detector at the Fermilab Tevatron p̄p collider. A data sample from 310pb -1 of integrated luminosity collected by triggering on a high transverse energy jet, ETjet, in coincidence with a recoil antiproton detected in a Roman pot spectrometer is used to measure the ratio of single-diffractive to inclusive-dijet event rates as a function of xp ̄ of the interacting parton in the antiproton, the Bjorken-x, xBjp̄, and a Q2(ETjet)2 in the ranges 10 -3-4GeV2. The t p̄ dependence is measured as a function of Q2 and xBjp̄ and compared with that of inclusive single diffraction dissociation. We find weak xBjp̄ and Q2 dependencies in the ratio of single diffractive to inclusive event rates, and no significant Q2 dependence in the diffractive t p̄ distributions. © 2012 American Physical Society., This work was supported by the U.S. Department of Energy and National Science Foundation; the Italian Istituto Nazionale di Fisica Nucleare; the Ministry of Education, Culture, Sports, Science and Technology of Japan; the Natural Sciences and Engineering Research Council of Canada; the National Science Council of the Republic of China; the Swiss National Science Foundation; the A. P. Sloan Foundation; the Bundesministerium für Bildung und Forschung, Germany; the Korean World Class University Program, the National Research Foundation of Korea; the Science and Technology Facilities Council and the Royal Society, UK; the Russian Foundation for Basic Research; the Ministerio de Ciencia e Innovación, and Programa Consolider-Ingenio 2010, Spain; the Slovak R&D Agency; the Academy of Finland; and the Australian Research Council (ARC).

Diboson production (WW+WZ+ZZ) has been observed at the Tevatron in hadronic decay modes dominated by the WW process. This paper describes the measurement of the cross section of WZ and ZZ events in final states with large E̸T and using b-jet identification as a tool to suppress WW contributions. Because of the limited energy resolution, we cannot distinguish between partially hadronic decays of WZ and ZZ, and we measure the sum of these processes. The number of signal events is extracted using a simultaneous fit to the invariant mass distribution of the two jets for events with two b-jet candidates and events with fewer than two b-jet candidates. We measure a cross section σ(pp̅ →WZ,ZZ)=5.8-3.0+3.6 pb, in agreement with the standard model., Department of Energy (US); National Science Foundation (US); Istituto Nazionale di Fisica Nucleare (Italia); Ministry of Education, Culture, Sports, Science and Technology (Japan); National Research Council of Canada; Swiss National Science Foundation; Alfred P. Sloan Foundation; Bundesministerium für Bildung und Forschung (Deutschland); National Research Foundation of Korea; Science and Technology Facilities Council (UK); The Royal Society (UK); Russian Foundation for Basic Research; Ministerio de Ciencia e Innovación (España); Slovak Research and Development Agency; Academy of Finland; Australian Research Council.

We report a measurement of the difference (ΔA CP) between time-integrated CP-violating asymmetries in D0→K +K - and D0→π +π - decays reconstructed in the full data set of proton-antiproton collisions collected by the Collider Detector at Fermilab, corresponding to 9.7fb -1 of integrated luminosity. The strong decay D *+→D0π + is used to identify the charm meson at production as D0 or D ̄0. We measure ΔA CP=[-0.62±0.21(stat)±0.10(syst)]%, which differs from zero by 2.7 Gaussian standard deviations. This result supports similar evidence for CP violation in charm-quark decays obtained in proton-proton collisions. © 2012 American Physical Society., This work was supported by the U.S. Department of Energy and National Science Foundation; the Italian Istituto Nazionale di Fisica Nucleare; the Ministry of Education, Culture, Sports, Science and Technology of Japan; the Natural Sciences and Engineering Research Council of Canada; the National Science Council of the Republic of China; the Swiss National Science Foundation; the A. P. Sloan Foundation; the Bundesministerium fÜr Bildung und Forschung, Germany; the Korean World Class University Program, the National Research Foundation of Korea; the Science and Technology Facilities Council and the Royal Society, United Kingdom; the Russian Foundation for Basic Research; the Ministerio de Ciencia e Innovación, and Programa Consolider-Ingenio 2010, Spain; the Slovak R&D Agency; the Academy of Finland.

Aaltonen, T. et al., We combine the results of searches for the standard model (SM) Higgs boson based on the full CDF Run II data set obtained from √s=1.96TeV pp̄ collisions at the Fermilab Tevatron corresponding to an integrated luminosity of 9.45fb -1. The searches are conducted for Higgs bosons that are produced in association with a W or Z boson, have masses in the range 90-150GeV/c2, and decay into bb̄ pairs. An excess of data is present that is inconsistent with the background prediction at the level of 2.5 standard deviations (the most significant local excess is 2.7 standard deviations). © 2012 American Physical Society., This work was supported by the U.S. Department of Energy and National Science Foundation; the Italian Istituto Nazionale di Fisica Nucleare; the Ministry of Education, Culture, Sports, Science and Technology of Japan; the Natural Sciences and Engineering Research Council of Canada; the National Science Council of the Republic of China; the Swiss National Science Foundation; the A. P. Sloan Foundation; the Bundesministerium für Bildung und Forschung, Germany; the Korean World Class University Program, the National Research Foundation of Korea; the Science and Technology Facilities Council and the Royal Society, UK; the Russian Foundation for Basic Research; the Ministerio de Ciencia e Innovación, and Programa Consolider-Ingenio 2010, Spain; the Slovak R&D Agency; the Academy of Finland; and the Australian Research Council (ARC).

We report a new search for dark matter in a data sample of an integrated luminosity of 7.7fb -1 of Tevatron pp̄ collisions at √s=1.96TeV, collected by the CDF II detector. We search for production of a dark-matter candidate, D, in association with a single top quark. We consider the hadronic decay mode of the top quark exclusively, yielding a final state of three jets with missing transverse energy. The data are consistent with the standard model; we thus set 95% confidence level upper limits on the cross section of the process pp̄→t+D as a function of the mass of the dark-matter candidate. The limits are approximately 0.5 pb for a dark-matter particle with mass in the range of 0-150GeV/c2. © 2012 American Physical Society., This work was supported by the U.S. Department of Energy and National Science Foundation; the Italian Istituto Nazionale di Fisica Nucleare; the Ministry of Education, Culture, Sports, Science and Technology of Japan; the Natural Sciences and Engineering Research Council of Canada; the National Science Council of the Republic of China; the Swiss National Science Foundation; the A. P. Sloan Foundation; the Bundesministerium für Bildung und Forschung, Germany; the Korean World Class University Program, the National Research Foundation of Korea; the Science and Technology Facilities Council and the Royal Society, UK; the Russian Foundation for Basic Research; the Ministerio de Ciencia e Innovación, and Programa Consolider-Ingenio 2010, Spain; the Slovak R&D Agency; the Academy of Finland; and the Australian Research Council (ARC).

We present a search for the rare radiative decay W ±→ π ±γ using data corresponding to an integrated luminosity of 4.3fb -1 of proton-antiproton collisions at a center-of-mass energy of 1.96 TeV collected by the CDF experiment at Fermilab. As no statistically significant signal is observed, we set a 95%-confidence-level upper limit on the relative branching fraction Γ(W ±→π ±γ)/Γ(W ±→e ±ν) at 6.4×10 -5, a factor of 10 improvement over the previous limit. © 2012 American Physical Society., Department of Energy (US); National Science Foundation (US); Istituto Nazionale di Fisica Nucleare (Italia); Ministry of Education, Culture, Sports, Science and Technology (Japan); National Research Council of Canada; Swiss National Science Foundation; Alfred P. Sloan Foundation; Bundesministerium für Bildung und Forschung (Deutschland); National Research Foundation of Korea; Science and Technology Facilities Council (UK); The Royal Society (UK); Russian Foundation for Basic Research; Ministerio de Ciencia e Innovación (España); Slovak Research and Development Agency; Academy of Finland; Australian Research Council.

Aaltonen, T. et al., We search for annihilation decay modes of neutral b mesons into pairs of charmless charged hadrons with the upgraded Collider Detector at the Fermilab Tevatron. Using a data sample corresponding to 6 fb-1 of integrated luminosity, we obtain the first evidence for the Bs0→π+π- decay, with a significance of 3.7σ, and a measured branching ratio B(Bs0→π+π-)=(0.57±0.15(stat)±0.10(syst))×10-6. A search for the B0→K+K- mode in the same sample yields a significance of 2.0σ, and a central value estimate B(B0→K+K-)=(0.23±0.10(stat)±0.10(syst))×10-6., This work was supported by the U.S. Department of Energy and National Science Foundation; the Italian Istituto Nazionale di Fisica Nucleare; the Ministry of Education, Culture, Sports, Science and Technology of Japan; the Natural Sciences and Engineering Research Council of Canada; the National Science Council of the Republic ofChina; the Swiss National Science Foundation; the A. P. Sloan Foundation; the Bundesministerium für Bildung und Forschung, Germany; the Korean World Class University Program, the National Research Foundation of Korea; the Science and Technology Facilities Council and the Royal Society, UK; the Russian Foundation for Basic Research; the Ministerio de Ciencia e Innovación, and Programa Consolider-Ingenio 2010, Spain; the Slovak R&D Agency; the Academy of Finland; and the Australian Research Council (ARC).

The angular distributions of muons from Υ(1S,2S,3S) →μ +μ - decays are measured using data from pp̄ collisions at √s=1.96TeV corresponding to an integrated luminosity of 6.7fb -1 and collected with the CDF II detector at the Fermilab Tevatron. This analysis is the first to report the full angular distributions as functions of transverse momentum p T for Υ mesons in both the Collins-Soper and s-channel helicity frames. This is also the first measurement of the spin alignment of Υ(3S) mesons. Within the kinematic range of Υ rapidity |y, This work was supported by the U.S. Department of Energy and National Science Foundation; the Italian Istituto Nazionale di Fisica Nucleare; the Ministry of Education, Culture, Sports, Science and Technology of Japan; the Natural Sciences and Engineering Research Council of Canada; the National Science Council of the Republic of China; the Swiss National Science Foundation; the A. P. Sloan Foundation; the Bundesministerium fÜr Bildung und Forschung, Germany; the Korean World Class University Program, the National Research Foundation of Korea; the Science and Technology Facilities Council and the Royal Society, United Kingdom; the Russian Foundation for Basic Research; the Ministerio de Ciencia e Innovación, and Programa Consolider-Ingenio 2010, Spain; the Slovak R&D Agency; the Academy of Finland; and the Australian Research Council (ARC).

We present a search for a new heavy particle X produced in association with a top quark, pp̄→t(X→t̄q) or pp̄→t̄(X̄ →tq̄), where q stands for up quarks and down quarks. Such a particle may explain the recent anomalous measurements of top-quark forward-backward asymmetry. If the light-flavor quark (q) is reconstructed as a jet (j), this gives a t̄+j or t+j resonance in tt̄+jet events, a previously unexplored experimental signature. In a sample of events with exactly one lepton, missing transverse momentum and at least five jets, corresponding to an integrated luminosity of 8.7fb -1 collected by the CDF II detector, we find the data to be consistent with the standard model. We set cross-section upper limits on the production (pp̄→Xt or X̄t̄) at 95% confidence level from 0.61 pb to 0.02 pb for X masses ranging from 200GeV/c2 to 800GeV/c2, respectively. © 2012 American Physical Society., This work was supported by the U.S. Department of Energy and National Science Foundation; the Italian Istituto Nazionale di Fisica Nucleare; the Ministry of Education, Culture, Sports, Science and Technology of Japan; the Natural Sciences and Engineering Research Council of Canada; the National Science Council of the Republic of China; the Swiss National Science Foundation; the A. P. Sloan Foundation; the Bundesministerium für Bildung und Forschung, Germany; the World Class University Program, the National Research Foundation of Korea; the Science and Technology Facilities Council and the Royal Society, UK; the Institut National de Physique Nucleaire et Physique des Particules/CNRS; the Russian Foundation for Basic Research; the Ministerio de Ciencia e Innovación, and Programa Consolider-Ingenio 2010, Spain; the Slovak R&DAgency; and the Academy of Finland.

Using data from pp̄ collisions at √s=1.96TeV recorded by the CDF II detector at the Fermilab Tevatron, we present improved measurements of the masses and first measurements of natural widths of the four bottom baryon resonance states Σb+, Σb*+ and Σb-, Σb*-. These states are fully reconstructed in their decay modes to Λb0π ± where Λb0→Λc+π - with Λc+→pK -π +. The analysis is based on a data sample corresponding to an integrated luminosity of 6.0fb -1 collected by an online event selection based on tracks displaced from the pp̄ interaction point. © 2012 American Physical Society., This work was supported by the U.S. Department of Energy and National Science Foundation; the Italian Istituto Nazionale di Fisica Nucleare; the Ministry of Education, Culture, Sports, Science and Technology of Japan; the Natural Sciences and Engineering Research Council of Canada; the National Science Council of the Republic ofChina; the Swiss National Science Foundation; the A. P. Sloan Foundation; the Bundesministerium für Bildung und Forschung, Germany; the Korean World Class University Program, the National Research Foundation of Korea; the Science and Technology Facilities Council and the Royal Society, UK; the Russian Foundation for Basic Research; the Ministerio de Ciencia e Innovación, and Programa Consolider-Ingenio 2010, Spain; the Slovak R&D Agency; the Academy of Finland; and the Australian Research Council (ARC).

7 páginas, 1 figura.-- PACS numbers: 13.20.He, 12.15.Mm, 12.60.Jv.-- CDF Collaboration: et al., A search has been performed for Bs0→μ+μ- and B0→μ+μ- decays using 7 fb-1 of integrated luminosity collected by the CDF II detector at the Fermilab Tevatron collider. The observed number of B0 candidates is consistent with background-only expectations and yields an upper limit on the branching fraction of B(B0→μ+μ-), This work was supported by the U.S. Department of Energy and National Science Foundation; the Italian Istituto Nazionale di Fisica Nucleare; the Ministry of Education, Culture, Sports, Science and Technology of Japan; the Natural Sciences and Engineering Research Council of Canada; the National Science Council of the Republic of China; the Swiss National Science Foundation; the A. P. Sloan Foundation; the Bundesministerium für Bildung und Forschung, Germany; the Korean World Class University Program, the National Research Foundation of Korea; the Science and Technology Facilities Council and the Royal Society, UK; the Institut National de Physique Nucleaire et Physique des Particules/CNRS; the Russian Foundation for Basic Research; the Ministerio de Ciencia e Innovación, and Programa Consolider-Ingenio 2010, Spain; the Slovak R&D Agency; the Academy of Finland; and the Australian Research Council (ARC).

7 páginas, 4 figuras, 2 tablas.-- PACS numbers: 14.65.Jk, 12.60.-i, 13.85.Rm, 14.80.-j.-- CDF Collaboration: et al., We present a search for a new particle T′ decaying to a top quark via T′→t+X, where X goes undetected. We use a data sample corresponding to 5.7 fb-1 of integrated luminosity of pp̅ collisions with √s=1.96 TeV, collected at Fermilab Tevatron by the CDF II detector. Our search for pair production of T′ is focused on the hadronic decay channel, pp̅ →T′T̅ ′→tt̅ +XX̅ →bqq̅ b̅ qq̅ +XX̅ . We interpret our results in terms of a model where T′ is an exotic fourth generation quark and X is a dark matter particle. The data are consistent with standard model expectations. We set a limit on the generic production of T′T̅ ′→tt̅ +XX̅ , excluding the fourth generation exotic quarks T′ at 95% confidence level up to mT′=400 GeV/c2 for mX≤70 GeV/c2., This work was supported by the U.S. Department of Energy and National Science Foundation; the Italian Istituto Nazionale di Fisica Nucleare; the Ministry of Education, Culture, Sports, Science and Technology of Japan; the Natural Sciences and Engineering Research Council of Canada; the National Science Council of the Republic of China; the Swiss National Science Foundation; the A. P. Sloan Foundation; the Bundesministerium für Bildung und Forschung, Germany; the Korean World Class University Program, the National Research Foundation of Korea; the Science and Technology Facilities Council and the Royal Society, UK; the Institut National de Physique Nucleaire et Physique des Particules/CNRS; the Russian Foundation for Basic Research; the Ministerio de Ciencia e Innovación, and Programa Consolider-Ingenio 2010, Spain; the Slovak R&D Agency; the Academy of Finland; and the Australian Research Council (ARC).

14 páginas, 11 figuras, 2 tablas.-- CDF Collaboration: et al., We present a study of Bs0 decays to the CP-odd final state J/ψf0(980) with J/ψ→μ+μ- and f0(980)→π+π-. Using pp̅ collision data with an integrated luminosity of 3.8 fb-1 collected by the CDF II detector at the Tevatron we measure a Bs0 lifetime of τ(Bs0→J/ψf0(980))=1.70-0.11+0.12(stat)±0.03(syst)ps. This is the first measurement of the Bs0 lifetime in a decay to a CP eigenstate and corresponds in the standard model to the lifetime of the heavy Bs0 eigenstate. We also measure the product of branching fractions of Bs0→J/ψf0(980) and f0(980)→π+π- relative to the product of branching fractions of Bs0→J/ψϕ and ϕ→K+K- to be Rf0/ϕ=0.257±0.020(stat)±0.014(syst), which is the most precise determination of this quantity to date., This work was supported by the U.S. Department of Energy and National Science Foundation; the Italian Istituto Nazionale di Fisica Nucleare; the Ministry of Education, Culture, Sports, Science and Technology of Japan; the Natural Sciences and Engineering Research Council of Canada; the National Science Council of the Republic of China; the Swiss National Science Foundation; the A. P. Sloan Foundation; the Bundesministerium für Bildung und Forschung, Germany; the Korean World Class University Program, the National Research Foundation of Korea; the Science and Technology Facilities Council and the Royal Society, UK; the Institut National de Physique Nucleaire et Physique des Particules/ CNRS; the Russian Foundation for Basic Research; the Ministerio de Ciencia e Innovación, and Programa Consolider-Ingenio 2010, Spain; the Slovak R&D Agency; and the Academy of Finland.

7 páginas, 3 figuras.-- PACS numbers: 13.85.-t, 11.30.Pb.-- CDF Collaboration: et al., We present the first model independent search for three-jet hadronic resonances within multijet events in √s=1.96 TeV pp̅ collisions at the Fermilab Tevatron using the CDF II detector. Pair production of supersymmetric gluinos and squarks with hadronic R-parity violating decays is employed as an example of a new physics benchmark for this signature. Selection criteria based on the kinematic properties of an ensemble of jet combinations within each event help to extract signal from copious QCD background. No significant excess outside the top quark mass window is observed in data with an integrated luminosity of 3.2 fb-1. We place 95% confidence level limits on the production cross section σ(pp̅ →XX′)×BR(g˜g˜→3 jet+3 jet) where X, X′=g˜, q˜, or q̅ ˜, with q˜, q̅ ˜→g˜+jet, as a function of gluino mass, in the range of 77 GeV/c2 to 240 GeV/c2., This work was supported by the U.S. Department of Energy and National Science Foundation; the Italian Istituto Nazionale di Fisica Nucleare; the Ministry of Education, Culture, Sports, Science and Technology of Japan; the Natural Sciences and Engineering Research Council of Canada; the National Science Council of the Republic of China; the Swiss National Science Foundation; the A. P. Sloan Foundation; the Bundesministerium für Bildung und Forschung, Germany; the Korean World Class University Program, the National Research Foundation of Korea; the Science and Technology Facilities Council and the Royal Society, U.K.; the Institut National de Physique Nucleaire et Physique des Particules/CNRS; the Russian Foundation for Basic Research; the Ministerio de Ciencia e Innovación, and Programa Consolider-Ingenio 2010, Spain; the Slovak R&D Agency; and the Academy of Finland.

17 páginas, 15 figuras, 9 tablas.-- PACS numbers: 14.20.Lq, 14.20.Gk.-- CDF Collaboration: et al., We report measurements of the resonance properties of Λc(2595)+ and Λc(2625)+ baryons in their decays to Λc+π+π- as well as Σc(2455)++,0 and Σc(2520)++,0 baryons in their decays to Λc+π± final states. These measurements are performed using data corresponding to 5.2 fb-1 of integrated luminosity from pp̅ collisions at √s=1.96 TeV, collected with the CDF II detector at the Fermilab Tevatron. Exploiting the largest available charmed baryon sample, we measure masses and decay widths with uncertainties comparable to the world averages for Σc states, and significantly smaller uncertainties than the world averages for excited Λc+ states., This work was supported by the U.S. Department of Energy and National Science Foundation; the Italian Istituto Nazionale di Fisica Nucleare; the Ministry of Education, Culture, Sports, Science and Technology of Japan; the Natural Sciences and Engineering Research Council of Canada; the National Science Council of the Republic of China; the Swiss National Science Foundation; the A.P. Sloan Foundation; the Bundesministerium für Bildung und Forschung, Germany; the Korean World Class University Program, the National Research Foundation of Korea; the Science and Technology Facilities Council and the Royal Society, UK; the Institut National de Physique Nucleaire et Physique des Particules/CNRS; the Russian Foundation for Basic Research; the Ministerio de Ciencia e Innovación, and Programa Consolider-Ingenio 2010, Spain; the Slovak R&D Agency; the Academy of Finland; and the Australian Research Council (ARC). We thank Andrew Blechman for providing feedback on the calculation of the ^c(2595)+ line shape.

18 páginas, 22 figuras, 17 tablas.-- PACS numbers: 12.60.Cn, 13.85.Rm, 14.70.Hp.-- CDF Collaboration: et al., We report on a search for anomalous production of Z boson pairs through a massive resonance decay in data corresponding to 2.5–2.9 fb-1 of integrated luminosity in pp̅ collisions at √s=1.96 TeV using the CDF II detector at the Fermilab Tevatron. This analysis, with more data and channels where the Z bosons decay to muons or jets, supersedes the 1.1 fb-1 four-electron channel result previously published by CDF. In order to maintain high efficiency for muons, we use a new forward tracking algorithm and muon identification requirements optimized for these high signal-to-background channels. Predicting the dominant backgrounds in each channel entirely from sideband data samples, we observe four-body invariant mass spectra above 300 GeV/c2 that are consistent with background. We set limits using the acceptance for a massive graviton resonance that are 7–20 times stronger than the previously published direct limits on resonant ZZ diboson production., This work was supported by the U. S. Department of Energy and National Science Foundation; the Italian Istituto Nazionale di Fisica Nucleare; the Ministry of Education, Culture, Sports, Science and Technology of Japan ; the Natural Sciences and Engineering Research Council of Canada; the National Science Council of the Republic of China ; the Swiss National Science Foundation; the A. P. Sloan Foundation; the Bundesministerium für Bildung und Forschung, Germany; the Korean World Class University Program, the National Research Foundation of Korea; the Science and Technology Facilities Council and the Royal Society, UK; the Institut National de Physique Nucleaire et Physique des Particules/CNRS; the Russian Foundation for Basic Research; the Ministerio de Ciencia e Innovación, and Programa Consolider-Ingenio 2010, Spain; the Slovak R&D Agency; and the Academy of Finland.

7 páginas, 3 figuras, 2 tablas.-- PACS numbers: 14.65.Jk, 12.60.-i, 13.85.Rm, 14.80.-j,-- CDF Collaboration: et al., We present a search for a new particle T′ decaying to top quark via T′→t+X, where X is an invisible particle. In a data sample with 4.8 fb-1 of integrated luminosity collected by the CDF II detector at Fermilab in pp̅ collisions with √s=1.96 TeV, we search for pair production of T′ in the lepton+jets channel, pp̅ →tt̅ +X+X→ℓνbqq′b+X+X. We interpret our results primarily in terms of a model where T′ are exotic fourth generation quarks and X are dark matter particles. Current direct and indirect bounds on such exotic quarks restrict their masses to be between 300 and 600 GeV/c2, the dark matter particle mass being anywhere below mT′. The data are consistent with standard model expectations, and we set 95% confidence level limits on the generic production of T′T̅ ′→tt̅ +X+X. For the dark matter model we exclude T′ at 95% confidence level up to mT′=360 GeV/c2 for mX≤100 GeV/c2., This work was supported by the U.S. Department of Energy and National Science Foundation; the Italian Istituto Nazionale di Fisica Nucleare; the Ministry of Education, Culture, Sports, Science and Technology of Japan; the Natural Sciences and Engineering Research Council of Canada; the National Science Council of the Republic of China; the Swiss National Science Foundation; the A. P. Sloan Foundation; the Bundesministerium für Bildung und Forschung, Germany; the World Class University Program, the National Research Foundation of Korea; the Science and Technology Facilities Council and the Royal Society, UK; the Institut National de Physique Nucleaire et Physique des Particules/CNRS; the Russian Foundation for Basic Research; the Ministerio de Ciencia e Innovación, and Programa Consolider-Ingenio 2010, Spain; the Slovak R&D Agency; and the Academy of Finland.

7 páginas, 1 figura, 2 tablas.-- PACS numbers: 14.65.Ha, 12.15.Ff, 13.85.Ni, 13.85.Qk.-- CDF Collaboration: et al., We present a direct measurement of the mass difference between t and t̅ quarks using tt̅ candidate events in the lepton+jets channel, collected with the CDF II detector at Fermilab’s 1.96 TeV Tevatron pp̅ Collider. We make an event by event estimate of the mass difference to construct templates for top quark pair signal events and background events. The resulting mass difference distribution of data is compared to templates of signals and background using a maximum likelihood fit. From a sample corresponding to an integrated luminosity of 5.6 fb-1, we measure a mass difference, ΔMtop=Mt-Mt̅ =-3.3±1.4(stat)±1.0(syst) GeV/c2, approximately 2 standard deviations away from the CPT hypothesis of zero mass difference., This work was supported by the U.S. Department of Energy and National Science Foundation; the Italian Istituto Nazionale di Fisica Nucleare; the Ministry of Education, Culture, Sports, Science and Technology of Japan; the Natural Sciences and Engineering Research Council of Canada; the National Science Council of the Republic of China; the Swiss National Science Foundation; the A. P. Sloan Foundation; the Bundesministerium für Bildung und Forschung, Germany; the Korean World Class University Program, the National Research Foundation of Korea; the Science and Technology Facilities Council and the Royal Society, UK; the Institut National de Physique Nucleaire et Physique des Particules/ CNRS; the Russian Foundation for Basic Research; the Ministerio de Ciencia e Innovación, and Programa Consolider-Ingenio 2010, Spain; the Slovak R&D Agency; the Academy of Finland; and the Australian Research Council (ARC).

8 páginas, 2 figuras, 1 tabla.-- Grupo de trabajo: CDF Collaboration.-- PACS numbers: 13.25.Hw, 13.30.Eg, 14.20.Mr, 14.40.Nd.-- et al., We report on a measurement of b-hadron lifetimes in the fully reconstructed decay modes B+→J/ψK+, B0→J/ψK*(892)0, B0→J/ψKs0, and Λb0→J/ψΛ0 using data corresponding to an integrated luminosity of 4.3 fb-1, collected by the CDF II detector at the Fermilab Tevatron. The measured lifetimes are τ(B+)=[1.639±0.009(stat)±0.009(syst)] ps, τ(B0)=[1.507±0.010(stat)±0.008(syst)] ps, and τ(Λb0)=[1.537±0.045(stat)±0.014(syst)] ps. The lifetime ratios are τ(B+)/τ(B0)=[1.088±0.009(stat)±0.004(syst)] and τ(Λb0)/τ(B0)=[1.020±0.030(stat)±0.008(syst)]. These are the most precise determinations of these quantities from a single experiment., This work was supported by the U.S. Department of Energy and National Science Foundation; the Italian Istituto Nazionale di Fisica Nucleare; the Ministry of Education, Culture, Sports, Science and Technology of Japan; the Natural Sciences and Engineering Research Council of Canada; the National Science Council of the Republic of China; the Swiss National Science Foundation; the A. P. Sloan Foundation; the Bundesministerium fu¨r Bildung und Forschung, Germany; the World Class University Program, the National Research Foundation of Korea; the Science and Technology Facilities Council and the Royal Society, U.K.; the Institut National de Physique Nucleaire et Physique des Particules/CNRS; the Russian Foundation for Basic Research; the Ministerio de Ciencia e Innovación, and Programa Consolider-Ingenio 2010, Spain; the Slovak R&D Agency; and the Academy of Finland.

8 páginas, 3 figuras, 1 tabla.-- CDF Collaboration: et al., We present a search for a new heavy charged vector boson W′ decaying to an electron-neutrino pair in pp̅ collisions at a center-of-mass energy of 1.96 TeV. The data were collected with the CDF II detector and correspond to an integrated luminosity of 5.3 fb-1. No significant excess above the standard model expectation is observed and we set upper limits on σ·B(W′→eν). Assuming standard model couplings to fermions and the neutrino from the W′ boson decay to be light, we exclude a W′ boson with mass less than 1.12 TeV/c2 at the 95% confidence level., This work was supported by the U.S. Department of Energy and National Science Foundation; the Italian Istituto Nazionale di Fisica Nucleare; the Ministry of Education, Culture, Sports, Science and Technology of Japan; the Natural Sciences and Engineering Research Council of Canada; the National Science Council of the Republic of China; the Swiss National Science Foundation; the A. P. Sloan Foundation; the Bundesministerium für Balduin Una Forschung, Germany; the World Class University Program, the National Research Foundation of Korea; the Science and Technology Facilities Council and the Royal Society, United Kingdom; the Institut National de Physique Nucleaire et Physique des Particules/CNRS and Universite Pierre et Marie Curie; the Russian Foundation for Basic Research; the Ministerio de Ciencia e Innovación, and Programa Consolider-Ingenio 2010, Spain; the Slovak R&D Agency; and the Academy of Finland.

8 páginas, 3 figuras, 3 tablas.-- CDF Collaboration: et al., We present the results of a search for pair production of a heavy toplike (t′) quark decaying to Wq final states using data corresponding to an integrated luminosity of 5.6 fb-1 collected by the CDF II detector in pp̅ collisions at √s=1.96 TeV. We perform parallel searches for t′→Wb and t′→Wq (where q is a generic down-type quark) in events containing a lepton and four or more jets. By performing a fit to the two-dimensional distribution of total transverse energy versus reconstructed t′ quark mass, we set upper limits on the t′t̅ ′ production cross section and exclude a standard model fourth-generation t′ quark decaying to Wb (Wq) with mass below 358 (340) GeV/c2 at 95% C.L., This work was supported by the U.S. Department of Energy and National Science Foundation; the Italian Istituto Nazionale di Fisica Nucleare; the Ministry of Education, Culture, Sports, Science and Technology of Japan; the Natural Sciences and Engineering Research Council of Canada; the National Science Council of the Republic of China; the Swiss National Science Foundation; the A. P. Sloan Foundation; the Bundesministerium für Bildung und Forschung, Germany; the World Class University Program, the National Research Foundation of Korea; the Science and Technology Facilities Council and the Royal Society, UK; the Institut National de Physique Nucleaire et Physique des Particules/CNRS; the Russian Foundation for Basic Research; the Ministerio de Ciencia e Innovación, and Programa Consolider-Ingenio 2010, Spain; the Slovak R&D Agency; and the Academy of Finland.

7 páginas, 2 figuras, 2 tablas.-- PACS numbers: 14.65.Jk, 12.60.-i, 13.85.Rm, 14.80.-j.-- CDF Collaboration: et al., We report the most sensitive direct search for pair production of fourth-generation bottomlike chiral quarks (b′) each decaying promptly to tW. We search for an excess of events with an electron or muon, at least five jets (one identified as due to a b or c quark), and an imbalance of transverse momentum by using data from pp̅ collisions collected by the CDF II detector at Fermilab with an integrated luminosity of 4.8 fb-1. We observe events consistent with background expectation, calculate upper limits on the b′ pair-production cross section (σbb̅ ′≲30 fb for mb′>375 GeV/c2), and exclude mb′, This work was supported by the U.S. Department of Energy and National Science Foundation; the Italian Istituto Nazionale di Fisica Nucleare; the Ministry of Education, Culture, Sports, Science and Technology of Japan; the Natural Sciences and Engineering Research Council of Canada; the National Science Council of the Republic of China; the Swiss National Science Foundation; the A. P. Sloan Foundation; the Bundesministerium für Bildung und Forschung, Germany; the World Class University Program, the National Research Foundation of Korea; the Science and Technology Facilities Council and the Royal Society, United Kingdom; the Institut National de Physique Nucleaire et Physique des Particules/CNRS; the Russian Foundation for Basic Research; the Ministerio de Ciencia e Innovación and Programa Consolider-Ingenio 2010, Spain; the Slovak R&D Agency; and the Academy of Finland.

9 páginas, 3 figuras, 2 tablas.-- PACS numbers: 13.85.Rm, 12.60.Jv, 13.85.Qk, 14.80.Ly.-- CDF Collaboration: et al., Using data corresponding to 6.0 fb-1 of pp̅ collisions at √s=1.96 TeV collected by the CDF II detector, we present a cross section measurement of top-quark pair production with an additional radiated photon in the central region with 10 GeV or more of transverse energy tt̅ γ. The events are selected by looking for a lepton (ℓ or μ), a photon (γ), significant transverse momentum imbalance (E̸T), large total transverse energy, and three or more jets, with at least one identified as containing a b quark (b). Using an event selection optimized for the tt̅ γ candidate sample, we also measure the cross section of tt̅ (σtt̅ ). We measure the tt̅ γ cross section (σtt̅ γ) to be 0.18±0.08 pb, and the ratio of σtt̅ γ to σtt̅ to be 0.024±0.009. We observe a probability of 0.0015 (3.0 standard deviations) of the background (non-tt̅ γ events alone producing 30 events or more., This work was supported by the U. S. Department of Energy and National Science Foundation; the Italian Istituto Nazionale di Fisica Nucleare; the Ministry of Education, Culture, Sports, Science and Technology of Japan; the Natural Sciences and Engineering Research Council of Canada; the National Science Council of the Republic of China; the Swiss National Science Foundation; the A. P. Sloan Foundation; the Bundesministerium fu¨ r Bildung und Forschung, Germany; the Korean World Class University Program, the National Research Foundation of Korea; the Science and Technology Facilities Council and the Royal Society, UK; the Institut National de Physique Nucleaire et Physique des Particules/CNRS; the Russian Foundation for Basic Research; the Ministerio de Ciencia e Innovación, and Programa Consolider-Ingenio 2010, Spain; the Slovak R&D Agency; the Academy of Finland; and the Australian Research Council (ARC).

12 páginas, 5 figuras, 3 tablas.-- PACS numbers: 14.65.Ha, 13.60.Hb.-- CDF Collaboration: et al., In this paper we report a measurement of the tt̅ production cross section in pp̅ collisions at √s=1.96 TeV using data corresponding to an integrated luminosity of 2.2 fb-1 collected with the CDF II detector at the Tevatron accelerator. We select events with significant missing transverse energy and high jet multiplicity. This measurement vetoes the presence of explicitly identified electrons and muons, thus enhancing the tau contribution of tt̅ decays. Signal events are discriminated from the background using a neural network, and heavy flavor jets are identified by a secondary-vertex tagging algorithm. We measure a tt̅ production cross section of 7.99±0.55(stat)±0.76(syst)±0.46(lumi) pb, assuming a top mass mtop=172.5 GeV/c2, in agreement with previous measurements and standard model predictions., This work was supported by the U.S. Department of Energy and National Science Foundation; the Italian Istituto Nazionale di Fisica Nucleare; the Ministry of Education, Culture, Sports, Science and Technology of Japan; the Natural Sciences and Engineering Research Council of Canada; the National Science Council of the Republic of China; the Swiss National Science Foundation; the A. P. Sloan Foundation; the Bundesministerium fuer Bildung und Forschung, Germany; the Korean Science and Engineering Foundation and the Korean Research Foundation; the Particle Physics and Astronomy Research Council and the Royal Society, UK; the Russian Foundation for Basic Research; the Comision Interministerial de Ciencia y Tecnologia, Spain; and in part by the European Community’s Human Potential Programme under Contract No. HPRN-CT-2002-00292, Probe for New Physics.