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Full-Text Articles in Physics
Search For Radiative B,-Hadron Decays In Pp̅ Collisions At √S=1.8 Tev, Darin Acosta, Kenneth A. Bloom, Collider Detector At Fermilab Collaboration
Search For Radiative B,-Hadron Decays In Pp̅ Collisions At √S=1.8 Tev, Darin Acosta, Kenneth A. Bloom, Collider Detector At Fermilab Collaboration
Kenneth Bloom Publications
We have performed a search for radiative b-hadron decays using events produced in pp̅ collisions at √s=1.8 TeV and collected by the Collider Detector at Fermilab. The decays we considered were B̅d0→K*0(→K-π+) γ, B̅s0→φ(→K+K-) γ, Λb0→ Λ(→pπ-) γ, and their charge conjugates. Two independent methods to identify photons from such decays were employed. In the first method, the photon was detected in the electromagnetic calorimeter. In the second method, the photon was identified …
Limits On Extra Dimensions And New Particle Production In The Exclusive Photon, Darin Acosta, Kenneth A. Bloom, Collider Detector At Fermilab Collaboration
Limits On Extra Dimensions And New Particle Production In The Exclusive Photon, Darin Acosta, Kenneth A. Bloom, Collider Detector At Fermilab Collaboration
Kenneth Bloom Publications
The exclusive γE/T signal has a small standard model cross section and is thus a channel sensitive to new physics. This signature is predicted by models with a superlight gravitino or with large extra spatial dimensions. We search for such signals at the Collider Detector at Fermilab, using 87 pb-1 of data at √s=1.8 TeV, and extract 95% C.L. limits on these processes. A limit of 221 GeV is set on the scale |F|1/2 in supersymmetric models. For 4, 6, and 8 extra dimensions, model-dependent limits on the fundamental mass scale MD of 0.55, 0.58, and …
Cross Section For Forward J/Ψ Production In Pp̅ Collisions At √S=1.8 Tev, Darin Acosta, Kenneth A. Bloom, Collider Detector At Fermilab Collaboration
Cross Section For Forward J/Ψ Production In Pp̅ Collisions At √S=1.8 Tev, Darin Acosta, Kenneth A. Bloom, Collider Detector At Fermilab Collaboration
Kenneth Bloom Publications
The inclusive cross section for J/ψ production times the branching ratio B(J/ψ→μ+μ-) has been measured in the forward pseudorapidity region: B×dσ[p̅+p→J/ψ(pT>10 GeV/c,2.1<|η|<2.6)+X]/dη=192±9(stat)±29(syst) pb. The results are based on 74.1±5.2 pb-1 of data collected by the CDF Collaboration at the Fermilab Tevatron Collider. The measurements extend earlier measurements of the D0 Collaboration to higher pTJ/ψ. In the kinematic range where the experiments partially overlap, these data are in good agreement with previous measurements.
Branching Ratio Measurements Of Exclusive B+ Decays To Charmonium With The Collider Detector At Fermilab, Darin Acosta, Kenneth A. Bloom, Collider Detector At Fermilab Collaboration
Branching Ratio Measurements Of Exclusive B+ Decays To Charmonium With The Collider Detector At Fermilab, Darin Acosta, Kenneth A. Bloom, Collider Detector At Fermilab Collaboration
Kenneth Bloom Publications
We report on measurements of the branching ratios of the decays B+→χc10 (1P)K+ and B+→J/ψK+π+π-, where χc10(1P)→J/ψγ and J/ψ→μ+μ- in pp̅ collisions at √s=1.8 TeV. Using a data sample from an integrated luminosity of 110 pb-1 collected by the Collider Detector at Fermilab we measure the branching ratios to be BR(B+→ χc10(1P)K+)=15.5±5.4(stat)±1.5(syst)±1.3(br)×10-4 and BR(B+→J/ψK+π+π-)=6.9±1.8(stat)±1.1(syst)±0.4(br)×10-4 where (br) is due …
Search For New Physics In Photon-Lepton Events In Pp̅ Collisions At √S= 1.8 Tev, Darin Acosta, Kenneth A. Bloom, Collider Detector At Fermilab Collaboration
Search For New Physics In Photon-Lepton Events In Pp̅ Collisions At √S= 1.8 Tev, Darin Acosta, Kenneth A. Bloom, Collider Detector At Fermilab Collaboration
Kenneth Bloom Publications
We present the results of a search in pp̅ collisions at √s = 1.8 TeV for anomalous production of events containing a photon and a lepton ( e or μ), both with large transverse energy, using 86 pb-1 of data collected with the Collider Detector at Fermilab during the 1994–1995 collider run at the Fermilab Tevatron. The presence of large missing transverse energy (ET), additional photons, or additional leptons in these events is also analyzed. The results are consistent with standard model expectations, with the possible exception of photon-lepton events with large ET, for …
Search For New Physics In Photon-Lepton Events In Pp̅ Collisions At √S =1.8 1.8 Tev, Darin Acosta, Kenneth A. Bloom, Collider Detector At Fermilab Collaboration
Search For New Physics In Photon-Lepton Events In Pp̅ Collisions At √S =1.8 1.8 Tev, Darin Acosta, Kenneth A. Bloom, Collider Detector At Fermilab Collaboration
Kenneth Bloom Publications
We present the results of a search in pp̅ collisions at √s =1.8 TeV for anomalous production of events containing a photon with large transverse energy and a lepton (e or m) with large transverse energy, using 86 pb-1 of data collected with the Collider Detector at Fermilab during the 1994–1995 collider run at the Fermilab Tevatron. The presence of large missing transverse energy (E/T), additional photons, or additional leptons in these events is also analyzed. The results are consistent with standard model expectations, with the possible exception of photon-lepton events with large E/T , …
Online Track Processor For The Cdf Upgrade, E. J. Thomson, C. Ciobanu, J.Y. Chung, J. Gerstenslager, J. Hoftiezer, R.E. Hughes, M. Johnson, P. Koehn, C. Neu, C. Sanchez, B.L. Winer, J. Dittman, J. Freeman, S. Holm, J.D. Lewis, C.J. Lin, T. Shaw, T. Wesson, Kenneth A. Bloom, D. Gerdes, N. Goldschmidt, J. Dawson, W. Haberichter
Online Track Processor For The Cdf Upgrade, E. J. Thomson, C. Ciobanu, J.Y. Chung, J. Gerstenslager, J. Hoftiezer, R.E. Hughes, M. Johnson, P. Koehn, C. Neu, C. Sanchez, B.L. Winer, J. Dittman, J. Freeman, S. Holm, J.D. Lewis, C.J. Lin, T. Shaw, T. Wesson, Kenneth A. Bloom, D. Gerdes, N. Goldschmidt, J. Dawson, W. Haberichter
Kenneth Bloom Publications
A trigger track processor, called the eXtremely Fast Tracker (XFT), has been designed for the Collider Detector at Fermilab (CDF) upgrade. This processor identifies high-transverse- momentum ( 1 5 GeV/c) charged particles in the new central outer tracking chamber for CDF II. The XFT design is highly parallel to handle the input rate of 183 Gb/s and the output rate of 44 Gb/s. The processor is pipelined and reports the result for a new event every 132 ns. The processor uses three stages: hit classification, segment finding, and segment linking. The pattern recognition algorithms for the three stages are implemented …
Search For The Decay BS→Μ+Μ-Φ In Pp̅ Collisions At √S =1.8 Tev, Darin Acosta, Kenneth A. Bloom, Collider Detector At Fermilab Collaboration
Search For The Decay BS→Μ+Μ-Φ In Pp̅ Collisions At √S =1.8 Tev, Darin Acosta, Kenneth A. Bloom, Collider Detector At Fermilab Collaboration
Kenneth Bloom Publications
We present a search for the flavor-changing neutral current decay Bs→μ+μ-φ in pp̅ collisions at √s =1.8 TeV, using 91 pb-1 of data collected at the Collider Detector at Fermilab (CDF).We find two candidate events for this decay, which are consistent with the background estimate of one event, and set an upper limit on the branching fraction of Ɓ(Bs→μ+μ-φ),6.7x10-5 at a 95% confidence level. This is the first limit on the branching fraction of this decay.
Measurement Of B-Meson Lifetimes Using Fully Reconstructed B Decays Produced, Darin Acosta, Kenneth A. Bloom, Collider Detector At Fermilab Collaboration
Measurement Of B-Meson Lifetimes Using Fully Reconstructed B Decays Produced, Darin Acosta, Kenneth A. Bloom, Collider Detector At Fermilab Collaboration
Kenneth Bloom Publications
We present an improved measurement of b-meson lifetimes using fully reconstructed B-decays produced in pp̅ collisions at √s =1.8 TeV, using 114 pb-1 of data collected at the Collider Detector at Fermilab. We obtain τ (B+)=1.636±0.058(stat) ±0.025(syst) ps, τ (B0)=1.497±0.073(stat) ±0.032(syst) ps and for the lifetime ratio τ (B+)/(B0)=1.093±0.066(stat) ±0.028(syst).
Search For Single-Top-Quark Production In Pp̅ Collisions At √S =1.8 Tev, Darin Acosta, Kenneth A. Bloom, Collider Detector At Fermilab Collaboration
Search For Single-Top-Quark Production In Pp̅ Collisions At √S =1.8 Tev, Darin Acosta, Kenneth A. Bloom, Collider Detector At Fermilab Collaboration
Kenneth Bloom Publications
We search for standard model single-top-quark production in the W-gluon fusion and W* channels using 106 pb-1 of data from pp̅ collisions at √s =1.8 TeV collected with the Collider Detector at Fermilab. We set an upper limit at 95% confidence level (C.L.) on the combined W-gluon fusion and W* single-top cross section of 14 pb, roughly six times larger than the standard model prediction. Separate 95% C.L. upper limits in the W-gluon fusion and W* channels are also determined and are found to be 13 and 18 pb, respectively.
Γ Production And Polarization In Pp̅ Collisions At √S= 1.8 Tev, Darin Acosta, Kenneth A. Bloom, Collider Detector At Fermilab Collaboration
Γ Production And Polarization In Pp̅ Collisions At √S= 1.8 Tev, Darin Acosta, Kenneth A. Bloom, Collider Detector At Fermilab Collaboration
Kenneth Bloom Publications
We report on measurements of the ϒ(1S), ϒ(2S), and ϒ(3S) differential cross sections (d2σ/dpTdy)|y|pp̅ collisions at √s = 1.8 TeV using a sample of 77±3 pb-1 collected by the collider detector at Fermilab. The three resonances were reconstructed through the decay ϒ→μ+μ-. The measured angular distribution of the muons in the ϒ(1S) rest frame is consistent with unpolarized meson production.
Charged Jet Evolution And The Underlying Event In Proton-Antiproton Collisions At 1.8 Tev, T. Affolder, Kenneth A. Bloom, Collider Detector At Fermilab Collaboration
Charged Jet Evolution And The Underlying Event In Proton-Antiproton Collisions At 1.8 Tev, T. Affolder, Kenneth A. Bloom, Collider Detector At Fermilab Collaboration
Kenneth Bloom Publications
The growth and development of ‘‘charged particle jets’’ produced in proton-antiproton collisions at 1.8 TeV are studied over a transverse momentum range from 0.5 GeV/c to 50 GeV/c. A variety of leading (highest transverse momentum) charged jet observables are compared with the QCD Monte Carlo models HERWIG, ISAJET, and PYTHIA. The models describe fairly well the multiplicity distribution of charged particles within the leading charged jet, the size of the leading charged jet, the radial distribution of charged particles and transverse momentum around the leading charged jet direction, and the momentum distribution of charged particles within the …
Diffractive Dijet Production At √S= 630 And 1800 Gev At The Fermilab Tevatron, Darin Acosta, Kenneth A. Bloom, Collider Detector At Fermilab Collaboration
Diffractive Dijet Production At √S= 630 And 1800 Gev At The Fermilab Tevatron, Darin Acosta, Kenneth A. Bloom, Collider Detector At Fermilab Collaboration
Kenneth Bloom Publications
We report a measurement of the diffractive structure function FjjD of the antiproton obtained from a study of dijet events produced in association with a leading antiproton in p̅p collisions at √s =630 GeV at the Fermilab Tevatron. The ratio of FjjD at √s =630 GeV to FjjD obtained from a similar measurement at √s =1800 GeV is compared with expectations from QCD factorization and other theoretical predictions. We also report a measurement of the ξ(x-Pomeron) and β(x of parton in Pomeron) dependence of FjjD at √s =1800 GeV. In the region …
Soft And Hard Interactions In Pp̅ Collisions At √S =1800 And 630 Gev, Darin Acosta, Kenneth A. Bloom, Collider Detector At Fermilab Collaboration
Soft And Hard Interactions In Pp̅ Collisions At √S =1800 And 630 Gev, Darin Acosta, Kenneth A. Bloom, Collider Detector At Fermilab Collaboration
Kenneth Bloom Publications
We present a study of pp̅ collisions at √s =1800 and 630 GeV collected using a minimum bias trigger by the CDF experiment in which the data set is divided into two classes corresponding to “soft” and “hard” interactions. For each subsample, the analysis includes measurements of the multiplicity, transverse momentum (pT) spectrum, and the average pT and event-by-event pT dispersion as a function of multiplicity. A comparison of results shows distinct differences in the behavior of the two samples as a function of the center of mass (c.m.) energy. We find evidence that the …
Measurement Of The B+ Total Cross Section And B+ Differential Cross Section Dσ/DPT In Pp̅ Collisions At √S=1.8 Tev, Darin Acosta, Kenneth A. Bloom, Collider Detector At Fermilab Collaboration
Measurement Of The B+ Total Cross Section And B+ Differential Cross Section Dσ/DPT In Pp̅ Collisions At √S=1.8 Tev, Darin Acosta, Kenneth A. Bloom, Collider Detector At Fermilab Collaboration
Kenneth Bloom Publications
We present measurements of the B+ meson total cross section and differential cross section dσ/dpT. The measurements use a 98±4 pb-1 sample of pp̅ collisions at √s=1.8 TeV collected by the CDF detector. Charged B meson candidates are reconstructed through the decay B±→J/ψK± with J/ψ→μ+μ-. The total cross section, measured in the central rapidity region |y|pT(B)> 6.0 GeV/c is 3.6±0.6 (stat⊕ syst), μb. The measured differential cross section is substantially larger than typical QCD predictions calculated to next-to-leading order.
Searches For New Physics In Events With A Photon And B-Quark Jet At Cdf, T. Affolder, Kenneth A. Bloom, Collider Detector At Fermilab Collaboration
Searches For New Physics In Events With A Photon And B-Quark Jet At Cdf, T. Affolder, Kenneth A. Bloom, Collider Detector At Fermilab Collaboration
Kenneth Bloom Publications
We have searched for evidence of physics beyond the standard model in events that include an energetic photon and an energetic b-quark jet, produced in 85 pb-1 of p̅p collisions at 1.8 TeV at the Tevatron Collider at Fermilab. This signature, containing at least one gauge boson and a third-generation quark, could arise in the production and decay of a pair of new particles, such as those predicted by supersymmetry, leading to a production rate exceeding standard model predictions. We also search these events for anomalous production of missing transverse energy, additional jets and leptons (e, …
Study Of The Heavy Flavor Content Of Jets Produced In Association With W Bosons In Pp̅ Collisions At √S =1.8 Tev, Darin Acosta, Kenneth A. Bloom, Collider Detector At Fermilab Collaboration
Study Of The Heavy Flavor Content Of Jets Produced In Association With W Bosons In Pp̅ Collisions At √S =1.8 Tev, Darin Acosta, Kenneth A. Bloom, Collider Detector At Fermilab Collaboration
Kenneth Bloom Publications
We present a detailed examination of the heavy flavor content of the W+ jet data sample collected with the Collider Detector at Fermilab during the 1992–1995 collider run at the Fermilab Tevatron. Jets containing heavy flavor quarks are selected via the identification of secondary vertices or semileptonic decays of b and c quarks. There is generally good agreement between the rates of secondary vertices and soft leptons in the data and in the standard model simulation including single and pair production of top quarks. An exception is the number of events in which a single jet has both a …
Search For New Heavy Particles In The Wz0 Final State In Pp̅ Collisions At √S = 1.8 Tev, T. Affolder, Kenneth A. Bloom, Collider Detector At Fermilab Collaboration
Search For New Heavy Particles In The Wz0 Final State In Pp̅ Collisions At √S = 1.8 Tev, T. Affolder, Kenneth A. Bloom, Collider Detector At Fermilab Collaboration
Kenneth Bloom Publications
We present the first general search for new heavy particles, X, which decay via X → WZ0 → eν + jj as a function of Mx and Γ(X) in pp̅ collisions at √s =1.8 TeV. No evidence is found for production of X in 110 pb-1 of data collected by the Collider Detector at Fermilab. General cross section limits are set at the 95% C.L. as a function of mass and width of the new particle. The results are further interpreted as mass limits on the production of new heavy charged vector bosons which decay via W′ …
Study Of B0 → J/Ψk(*)0Π+Π- Decays With The Collider Detector At Fermilab, T. Affolder, Kenneth A. Bloom, Collider Detector At Fermilab Collaboration
Study Of B0 → J/Ψk(*)0Π+Π- Decays With The Collider Detector At Fermilab, T. Affolder, Kenneth A. Bloom, Collider Detector At Fermilab Collaboration
Kenneth Bloom Publications
We report a study of the decaysB0 →J/ψK(*)0π+π-, which involve the creation of a uu̅ or dd̅ quark pair in addition to a b̅→ c̅(cs̅) decay. The data sample consists of 110 pb-1 of pp̅ collisions at √s=1.8 TeV collected by the CDF detector at the Fermilab Tevatron collider during 1992–1995. We measure the branching fractions to be Ɓ(B0 → J/ψK(*)0π+π-) = (6.6 ± 1.9 ± 1.1) x 10-4 and Ɓ(B0 → J/ψK(*)0π+π …
Search For Gluinos And Scalar Quarks In Pp̅ Collisions At √S = 1.8 Tev Using The Missing Energy Plus Multijets Signature, T. Affolder, Kenneth A. Bloom, Collider Detector At Fermilab Collaboration
Search For Gluinos And Scalar Quarks In Pp̅ Collisions At √S = 1.8 Tev Using The Missing Energy Plus Multijets Signature, T. Affolder, Kenneth A. Bloom, Collider Detector At Fermilab Collaboration
Kenneth Bloom Publications
We have performed a search for gluinos (g̃) and scalar quarks (q̃,/i>) in a data sample of 84 pb-1 of pp̅ collisions at √s =1.8 TeV, recorded by the Collider Detector at Fermilab. We investigate the final state of large missing transverse energy and three or more jets, a characteristic signature in R-parityconserving supersymmetric models. The analysis has been performed “blind,” in that the inspection of the signal region is made only after the predictions from standard model backgrounds have been calculated. Comparing the data with predictions of constrained supersymmetric models, we exclude gluino …
Measurement Of The Strong Coupling Constant From Inclusive Jet Production At The Tevatron P̅P Collider, T. Affolder, Kenneth A. Bloom, Collider Detector At Fermilab Collaboration
Measurement Of The Strong Coupling Constant From Inclusive Jet Production At The Tevatron P̅P Collider, T. Affolder, Kenneth A. Bloom, Collider Detector At Fermilab Collaboration
Kenneth Bloom Publications
We report a measurement of the strong coupling constant, αs(Mz ), extracted from inclusive jet production in pp̅ collisions at √s =1800 GeV. The QCD prediction for the evolution of αs with jet transverse energy ET is tested over the range 40 TET for the renormalization scale. The data show good agreement with QCD in the region below 250 GeV. The value of αs at the mass of the Z0 boson averaged over the range 40 < T < 250 GeV is found to be αs(Mz )= 0.1178 ± 0.0001(stat)-0.0095+0.0081 (expt. syst). The associated theoretical uncertainties …
Cross Section And Heavy Quark Composition Of Γ+Μ Events Produced In Pp̅ Collisions, T. Affolder, Kenneth A. Bloom, Collider Detector At Fermilab Collaboration
Cross Section And Heavy Quark Composition Of Γ+Μ Events Produced In Pp̅ Collisions, T. Affolder, Kenneth A. Bloom, Collider Detector At Fermilab Collaboration
Kenneth Bloom Publications
We present a measurement of the cross section and the first measurement of the heavy flavor content of associated direct photon + muon events produced in hadronic collisions. These measurements come from a sample of 1.8 TeV pp̅ collisions recorded with the Collider Detector at Fermilab. Quantum chromodynamics (QCD) predicts that these events are primarily due to the Compton scattering process cg→cγ , with the final-state charm quark producing a muon. The cross section for events with a photon transverse momentum between 12 and 40 GeV/c is measured to be 46.8±6.3±7.5 pb, which is two standard deviations below the …