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Full-Text Articles in Physical Sciences and Mathematics
Search For Gluinos And Squarks Using Like-Sign Dileptons In Pp̅ Collisions At √S= 1.8 Tev, T. Affolder, Kenneth A. Bloom, Collider Detector At Fermilab Collaboration
Search For Gluinos And Squarks Using Like-Sign Dileptons In Pp̅ Collisions At √S= 1.8 Tev, T. Affolder, Kenneth A. Bloom, Collider Detector At Fermilab Collaboration
Kenneth Bloom Publications
We present results of the first search for like-sign dilepton (e±e±, e± μ±, μ± μ±) events associated with multijets and large missing energy using 106 pb-1 of data in pp̅ collisions at √s= 1.8 TeV collected during 1992–1995 by the CDF experiment. Finding no events that pass our selection, we examine pair production of gluinos (g̃) and squarks (q̃) in a constrained framework of the minimal supersymmetric standard model. At tanβ =2 and μ = -800 GeV/c2, we set 95% confidence …
Observation Of Diffractive J/Ψ Production At The Fermilab Tevatron, T. Affolder, Kenneth A. Bloom, Collider Detector At Fermilab Collaboration
Observation Of Diffractive J/Ψ Production At The Fermilab Tevatron, T. Affolder, Kenneth A. Bloom, Collider Detector At Fermilab Collaboration
Kenneth Bloom Publications
We report the first observation of diffractive J/ψ(→μ+μ-) production in p̅p collisions at √s= 1.8 TeV. Diffractive events are identified by their rapidity gap signature. In a sample of events with two muons of transverse momentum pT,/sub> μ> 2 GeV/c within the pseudorapidity region |η| J/ψ production rates is found to be RJ/ψ=[1.45 ± 0.25]%. The ratio RJ/ψ(x) is presented as a function of x-Bjorken. By combining it with our previously measured corresponding ratio Rjj(x) for diffractive dijet production, we extract a value of 0.59 …
Search For Quark-Lepton Compositeness And A Heavy W′ Boson Using The Eν Channel In Pp̅ Collisions At √S = 1.8 Tev, T. Affolder, Kenneth A. Bloom, Collider Detector At Fermilab Collaboration
Search For Quark-Lepton Compositeness And A Heavy W′ Boson Using The Eν Channel In Pp̅ Collisions At √S = 1.8 Tev, T. Affolder, Kenneth A. Bloom, Collider Detector At Fermilab Collaboration
Kenneth Bloom Publications
We present searches for quark-lepton compositeness and a heavy W′ boson at high electron-neutrino transverse mass. We use ~110 pb-1 of data collected in pp̅ collisions at √s= 1.8 TeV by the CDF Collaboration during 1992–1995. The data are consistent with standard model expectations. Limits are set on the quark-lepton compositeness scale Λ, the ratio of partial cross sections σ (W′ → eν)/ σ (W → eν), and the mass of a W′ boson with standard model couplings. We exclude Λ< 2.81 TeV and a W′ boson with mass below 754 GeV/c2 at the 95% …
Charged-Particle Multiplicity Pp̅ Collisions At √S = 1.8 Tev, T. Affolder, Kenneth A. Bloom, Collider Detector At Fermilab Collaboration
Charged-Particle Multiplicity Pp̅ Collisions At √S = 1.8 Tev, T. Affolder, Kenneth A. Bloom, Collider Detector At Fermilab Collaboration
Kenneth Bloom Publications
We report on a measurement of the mean charged-particle multiplicity of jets in dijet events with dijet masses in the range 80-630 GeV/c2, produced at the Tevatron in pp̅ collisions with √s= 1.8 TeV and recorded by the Collider Detector at Fermilab. The data are fit to perturbative-QCD calculations carried out in the framework of the modified leading log approximation and the hypothesis of local parton-hadron duality. The fit yields values for two parameters in that framework: the ratio of parton multiplicities in gluon and quark jets, r=Ng-jet partons/Nq-jet partons =1.7 ± …
Search For Narrow Diphoton Resonances And For Γγ+W/Z Signatures In Pp̅ Collisions At √S=1.8 Tev, T. Affolder, Kenneth A. Bloom, Collider Detector At Fermilab Collaboration
Search For Narrow Diphoton Resonances And For Γγ+W/Z Signatures In Pp̅ Collisions At √S=1.8 Tev, T. Affolder, Kenneth A. Bloom, Collider Detector At Fermilab Collaboration
Kenneth Bloom Publications
We present results of searches for diphoton resonances produced both inclusively and also in association with a vector boson (W or Z) using 100 pb-1 of pp̅ collisions using the CDF detector. We set upper limits on the product of cross section times branching ratio for both pp̅→ γγ+X and pp̅→ γγ+ W/Z. Comparing the inclusive production to the expectations from heavy sgoldstinos we derive limits on the supersymmetrybreaking scale √F in the TeV range, depending on the sgoldstino mass and the choice of other parameters. Also, using a NLO prediction for the associated …
Observation Of Orbitally Excited B Mesons In Pp̅ Collisions At √S =1.8 Tev, T. Affolder, Kenneth A. Bloom, Collider Detector At Fermilab Collaboration
Observation Of Orbitally Excited B Mesons In Pp̅ Collisions At √S =1.8 Tev, T. Affolder, Kenneth A. Bloom, Collider Detector At Fermilab Collaboration
Kenneth Bloom Publications
We measure the relative rate of production of orbitally excited (L=1) states of B mesons (B**) by observing their decays into B π ±. We reconstruct B mesons through semileptonic decay channels using data collected in pp̅ collisions at √s =1.8 TeV. The fraction of light B mesons that are produced as L=1B** states is measured to be 0.28±0.06(stat) ±0.03(syst). We also measure the collective mass of the B** states, and quantify the result by quoting the (model-dependent) mass of the lowest B** state to be m (B1)=5.71 ±0.02 GeV/ …
Double Diffraction Dissociation At The Fermilab Tevatron Collider, T. Affolder, Kenneth A. Bloom, Collider Detector At Fermilab Collaboration
Double Diffraction Dissociation At The Fermilab Tevatron Collider, T. Affolder, Kenneth A. Bloom, Collider Detector At Fermilab Collaboration
Kenneth Bloom Publications
We present results from a measurement of double diffraction dissociation in p̅p collisions at the Fermilab Tevatron collider. The production cross section for events with a central pseudorapidity gap of width Δη0 > 3 (overlapping η=0) is found to be 4.43±0.02(stat) ± 1.18(syst) mb [3.42 ± 0.01(stat) ± 1.09(syst) mb] at √s=1800[630] GeV. Our results are compared with previous measurements and with predictions based on Regge theory and factorization.
Measurement Of DΣ/Dm And Forward-Backward Charge Asymmetry For High-Mass Drell-Yan E+E- Pairs From Pp̅ Collisions At √S = 1.8 Tev, T. Affolder, Kenneth A. Bloom, Collider Detector At Fermilab Collaboration
Measurement Of DΣ/Dm And Forward-Backward Charge Asymmetry For High-Mass Drell-Yan E+E- Pairs From Pp̅ Collisions At √S = 1.8 Tev, T. Affolder, Kenneth A. Bloom, Collider Detector At Fermilab Collaboration
Kenneth Bloom Publications
We report on a measurement of the mass dependence of the forward-backward charge asymmetry, AFB, and production cross section dσ /dM for e+e- pairs with mass Mee> 40 GeV/c2. The data sample consists of 108 pb-1 of pp̅ collisions at √s= 1.8 TeV taken by the Collider Detector at Fermilab during 1992–1995. The measured asymmetry and dσ/dM are compared with the predictions of the standard model and a model with an extra Z′ gauge boson.
Measurement Of The Top Quark PT Distribution, T. Affolder, Kenneth A. Bloom, Collider Detector At Fermilab Collaboration
Measurement Of The Top Quark PT Distribution, T. Affolder, Kenneth A. Bloom, Collider Detector At Fermilab Collaboration
Kenneth Bloom Publications
We have measured the pT distribution of top quarks that are pair produced in pp̅ collisions at √s=1.8 TeV using a sample of tt̅ decays in which we observe a single high-pT charged lepton, a neutrino, and four or more jets. We use a likelihood technique that corrects for the experimental bias introduced due to event reconstruction and detector resolution effects. The observed distribution is consistent with the standard model prediction. We use these data to place limits on the production of high-pT top quarks suggested in some models of anomalous top quark pair production.
Measurement Of The W Boson Mass With The Collider Detector At Fermilab, T. Affolder, Kenneth A. Bloom, Collider Detector At Fermilab Collaboration
Measurement Of The W Boson Mass With The Collider Detector At Fermilab, T. Affolder, Kenneth A. Bloom, Collider Detector At Fermilab Collaboration
Kenneth Bloom Publications
We present a measurement of the W boson mass using data collected with the CDF detector during the 1994–1995 collider run at the Fermilab Tevatron. A fit to the transverse mass spectrum of a sample of 30115 W→eν events recorded in an integrated luminosity of 84 pb-1 gives a mass Mw=80.473±0.065(stat) ±0.092(syst) GeVc2. A fit to the transverse mass spectrum of a sample of 14740 W→μν events from 80 pb-1 gives a mass Mw=80.465±0.100(stat) ±0.103(syst) GeV/c2. The dominant contributions to the systematic uncertainties are the …
Measurement Of The Inclusive Jet Cross Section In Pp̅ Collisions At √S =1.8 Tev, T. Affolder, Kenneth A. Bloom, Collider Detector At Fermilab Collaboration
Measurement Of The Inclusive Jet Cross Section In Pp̅ Collisions At √S =1.8 Tev, T. Affolder, Kenneth A. Bloom, Collider Detector At Fermilab Collaboration
Kenneth Bloom Publications
We present results from the measurement of the inclusive jet cross section for jet transverse energies from 40 to 465 GeV in the pseudorapidity range 0.1<|η|-1 of data collected by the CDF Collaboration at the Fermilab Tevatron collider. The data are consistent with previously published results. The data are also consistent with QCD predictions given the flexibility allowed from current knowledge of the proton parton distributions. We develop a new procedure for ranking the agreement of the parton distributions with data and find that the data are best described by QCD predictions using the parton distribution functions which have a large gluon contribution at high ET (CTEQ4HJ).
Measurement Of The Tt̅ Production Cross Section In Pp̅ Collisions At √S =1.8 Tev, T. Affolder, Kenneth A. Bloom, Collider Detector At Fermilab Collaboration
Measurement Of The Tt̅ Production Cross Section In Pp̅ Collisions At √S =1.8 Tev, T. Affolder, Kenneth A. Bloom, Collider Detector At Fermilab Collaboration
Kenneth Bloom Publications
We update the measurement of the tt̅ production cross section using the CDF detector at the Fermilab Tevatron. This measurement uses tt̅ decays to the final states e+ν+jets and μ+ν+jets. We search for b quarks from t decays via secondary-vertex identification or the identification of semileptonic decays of the b and cascade c quarks. The background to the tt̅ production is determined primarily through a Monte Carlo simulation. However, we calibrate the simulation and evaluate its uncertainty using several independent data samples. For a top quark mass of 175 GeV/c2, we measure σ t t¯ …
Measurement Of The Two-Jet Differential Cross Section In Pp̅ Collisions At √S=1800 Gev, T. Affolder, Kenneth A. Bloom, Collider Detector At Fermilab Collaboration
Measurement Of The Two-Jet Differential Cross Section In Pp̅ Collisions At √S=1800 Gev, T. Affolder, Kenneth A. Bloom, Collider Detector At Fermilab Collaboration
Kenneth Bloom Publications
A measurement is presented of the two-jet differential cross section d3σ/dETd η1d η2 at center of mass energy √s =1800 GeV in pp̅ collisions. The results are based on an integrated luminosity of 86 pb-1 collected during 1994 to 1995 by the CDF Collaboration at the Fermilab Tevatron collider. The differential cross section is measured as a function of the transverse energy ET of a jet in the pseudorapidity region 0.1 < | η1| < 0.7 for four different pseudorapidity bins of a second jet restricted to 0.1 < |η2| < 3.0. The results are compared with next-to-leading order QCD calculations determined using the CTEQ4 and MRST sets of parton distribution functions. None of the sets examined in this analysis provides a good description of the data.
Search For Neutral Supersymmetric Higgs Bosons In Pp̅ Collisions At √S = 1.8 Tev, T. Affolder, Kenneth A. Bloom, Collider Detector At Fermilab Collaboration
Search For Neutral Supersymmetric Higgs Bosons In Pp̅ Collisions At √S = 1.8 Tev, T. Affolder, Kenneth A. Bloom, Collider Detector At Fermilab Collaboration
Kenneth Bloom Publications
We present the results of a search for neutral Higgs bosons produced in association with b quarks in pp̅→ bb̅bb̅ final states with 91 ± 7 pb-1 of pp̅ collisions at √s =1.8 TeV recorded by the Collider Detector at Fermilab. We find no evidence of such a signal and the data are interpreted in the context of the neutral Higgs sector of the minimal supersymmetric extension of the standard model. With basic parameter choices for the supersymmetric scale and the stop-quark mixing, we derive 95% C.L. lower mass limits for neutral Higgs bosons for tanb values …
Search For The Supersymmetric Partner Of The Top Quark In Pp̅ Collisions At √S=1.8 Tev, T. Affolder, Kenneth A. Bloom, Collider Detector At Fermilab Collaboration
Search For The Supersymmetric Partner Of The Top Quark In Pp̅ Collisions At √S=1.8 Tev, T. Affolder, Kenneth A. Bloom, Collider Detector At Fermilab Collaboration
Kenneth Bloom Publications
We report on a search for the supersymmetric partner of the top quark (top squark) produced in tt̅ events using 110 pb-1 of pp̅ collisions at √s =1.8 TeV recorded with the Collider Detector at Fermilab. In the case of a light top squark, the decay of the top quark into a top squark plus the lightest supersymmetric particle (LSP) could have a significant branching ratio. The observed events are consistent with standard model tt̅ production and decay. Hence, we set limits on the branching ratio of the top quark decaying into a top squark plus LSP, excluding branching …
Production Of Χ C1 And Χ C2 In Pp̅ Collisions At √S= 1.8 Tev, T. Affolder, Kenneth A. Bloom, Collider Detector At Fermilab Collaboration
Production Of Χ C1 And Χ C2 In Pp̅ Collisions At √S= 1.8 Tev, T. Affolder, Kenneth A. Bloom, Collider Detector At Fermilab Collaboration
Kenneth Bloom Publications
We have measured the ratio of prompt production rates of the charmonium states χ c1 and χ c2 in 110 pb-1 of pp̅ collisions at √s= 1.8 TeV. The photon from their decay into J/ψγ is reconstructed through conversion into e+e- pairs. The energy resolution this technique provides makes the resolution of the two states possible. We find the ratio of production cross sections (σ χ c2/ σ χ c1=0.96 ± 0.27(stat) ± 0.11(syst) for events with pT(J/ψ)> 4.0 GeV/c, |η(J/ψ)|, 0.6, and pT …
First Measurement Of The Ratio B (T →Wb)/ B (T → Wq) And Associated Limit On The Cabibbo-Kobayashi-Maskawa Element |VTb|, T. Affolder, Kenneth A. Bloom, Collider Detector At Fermilab Collaboration
First Measurement Of The Ratio B (T →Wb)/ B (T → Wq) And Associated Limit On The Cabibbo-Kobayashi-Maskawa Element |VTb|, T. Affolder, Kenneth A. Bloom, Collider Detector At Fermilab Collaboration
Kenneth Bloom Publications
We present the first measurement of the ratio of branching fractions R≡ B(t→ Wb)/B(t →Wq) from pp̅ collisions at √s =1.8 TeV. The data set corresponds to 109 pb-1 of data recorded by the Collider Detector at Fermilab during the 1992–95 Tevatron run. We measure R=-0.24+0.31(stat + syst) or R >0.61 (0.56) at 90% (95)% C.L., in agreement with the standard model predictions. This measurement yields a limit on the Cabibbo-Kobayashi-Maskawa quark mixing matrix element |Vtb| under the assumption of three generations …
Tests Of Enhanced Leading Order Qcd In W Boson Plus Jets Events From 1.8 Tev P̅P Collisions, T. Affolder, Kenneth A. Bloom, Collider Detector At Fermilab Collaboration
Tests Of Enhanced Leading Order Qcd In W Boson Plus Jets Events From 1.8 Tev P̅P Collisions, T. Affolder, Kenneth A. Bloom, Collider Detector At Fermilab Collaboration
Kenneth Bloom Publications
We present a study of events with W bosons and hadronic jets produced in p̅p collisions at a center of mass energy of 1.8 TeV. The data consist of 51400 W→eν decay candidates from 108 pb-1 of integrated luminosity collected using the CDF detector at the Fermilab Tevatron collider. Cross sections and jet production properties have been measured for W+≥1 to ≥4 jet events. The data compare well to predictions of leading-order QCD matrix element calculations with added gluon radiation and simulated parton fragmentation.
Measurement Of The Top Quark Mass With The Collider Detector At Fermilab, T. Affolder, Kenneth A. Bloom, Collider Detector At Fermilab Collaboration
Measurement Of The Top Quark Mass With The Collider Detector At Fermilab, T. Affolder, Kenneth A. Bloom, Collider Detector At Fermilab Collaboration
Kenneth Bloom Publications
This report describes a measurement of the top quark mass in pp̅ collisions at a center of mass energy of 1.8 TeV. The data sample was collected with the CDF detector during the 1992–1995 collider run at the Fermilab Tevatron, and corresponds to an integrated luminosity of 106 pb-1. Candidate tt̅ events in the ‘‘lepton+jets’’ decay channel provide our most precise measurement of the top quark mass. For each event a top quark mass is determined by using energy and momentum constraints on the production of the tt̅ pair and its subsequent decay. A likelihood fit to the …
Measurement Of Dσ/Dy For High Mass Drell-Yan E+E- Pairs From Pp̅ Collisions At √S =1.8 Tev, T. Affolder, Kenneth A. Bloom, Collider Detector At Fermilab Collaboration
Measurement Of Dσ/Dy For High Mass Drell-Yan E+E- Pairs From Pp̅ Collisions At √S =1.8 Tev, T. Affolder, Kenneth A. Bloom, Collider Detector At Fermilab Collaboration
Kenneth Bloom Publications
No abstract provided.
Measurement Of Dσ/Dy For High Mass Drell-Yan E+E- Pairs From Pp̅ Collisions At √S =1.8 Tev, T. Affolder, Kenneth A. Bloom, Collider Detector At Fermilab Collaboration
Measurement Of Dσ/Dy For High Mass Drell-Yan E+E- Pairs From Pp̅ Collisions At √S =1.8 Tev, T. Affolder, Kenneth A. Bloom, Collider Detector At Fermilab Collaboration
Kenneth Bloom Publications
We report on the first measurement of the rapidity distribution dσ/dy over nearly the entire kinematic region of rapidity for e+e- pairs in both the Z-boson region of 66<Mee/c2 and in the high mass region of Mee>116 GeV/c2. The data sample consists of 108 pb-1 of pp̅ collisions at √s =1.8 TeV taken by the Collider Detector at Fermilab during 1992–1995. The total cross section in the Z-boson region is measured to be 252±11 pb. The measured total cross section and dσ/dy are compared …