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B-Physics results from D0

Description: We report on preliminary measurements of the inclusive single muon and dimuon cross sections in p{bar p} collisions at {radical}s = 1.8 TeV using the D0 detector at the Fermilab collider. From these results, we extract the cross section for b-quark production for the kinematic range {vert_bar}yb{vert_bar} < 1.0 and 6 < p{sub t}{sup b} < 50 GeV/c. We also report measurements on the J/{psi} production, and correlations between muons in dimuon events.
Date: December 1, 1994
Creator: Hedin, D. & Markosky, L.
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Partner: UNT Libraries Government Documents Department
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A study of K{sub s} {Lambda} and {bar {Lambda}} production in hadronic Z{sup 0} decays

Description: We present a preliminary measurement of the inclusive production rates of K{sub s}, A and X hadrons produced in e{sup +}e{sup {minus}} annihilation at the Z{sup 0} pole. The analysis is based upon approximately 50K Z{sup 0} decays collected in the SLD experiment at SLAC in 1993. The observed rates of (K{sub s}) = 1.02 {plus_minus} 0.02 {plus_minus} 0.09 and ({Lambda}) + ({bar {Lambda}}) = 0.38 {plus_minus} 0.01 {plus_minus} 0.04 are consistent with previous measurements. Our differential cross … more
Date: August 1, 1994
Creator: Baird, K. G.
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Partner: UNT Libraries Government Documents Department
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B physics with CDF: Recent results and future prospects

Description: Using data collected during the 1992--1993 collider run, we report on measurements of the B{sup o}, B{sup +}, and B{sub s} lifetimes. We also present our revised measurement of the B{sub s} mass. Production studies involving inclusive modes decaying into J/{psi} or {psi}(2S), semileptonic decays involving D{sup o} or D*{sup +} mesons, and fully reconstructed B mesons are also presented. We present the prospects for future work with this data, as well as that being collected in the 1994--1995 co… more
Date: August 1994
Creator: Mueller, James A.
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Partner: UNT Libraries Government Documents Department
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Production of W and Z bosons at D0

Description: Preliminary results from the DO experiment are presented on production properties of the W{sup {plus_minus}} and Z{sup 0} gauge bosons using final states containing electrons and muons. The DO detector has accumulated 16.7 pb{sup {minus}1} of data at the Fermilab {bar p}p Tevatron collider. Based on a subset of this data preliminary measurements of the W{sup {plus_minus}} and Z{sup 0} production cross section and a measurement of {alpha}{sub s} at Q{sup 2} = M{sub W}{sup 2} derived from the rat… more
Date: January 1, 1994
Creator: Graf, N. A. & Collaboration, The D0
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Partner: UNT Libraries Government Documents Department
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Search for top in lepton + jets in D0 using a topological tag

Description: We have searched for production of t{bar t} pairs in p{bar p} interactions at 1.8 TeV center-of-mass energy at the FNAL Tevatron collider. The search assumes standard model decay for top quark into W + b quark. We observe in {mu} + jets and 14 + jets final states a small, not statistically significant, excess above the background estimated by two different methods. The results presented are preliminary.
Date: December 1, 1994
Creator: Protopopescu, S.
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Partner: UNT Libraries Government Documents Department
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Some recent experimental results from Fermilab

Description: The aim of this talk was to give an impression of the tremendous range and depth of the data being produced by experiments at Fermilab, both fixed target and collider. Despite the generous allotment of time it was not possible to do more than scratch the surface of some subjects. The collider experiments, using the measurements of the W mass and with top search and mass limits, are approaching the situation where a statement about the Higgs mass, or a sensitive test of the consistency of the st… more
Date: February 1, 1994
Creator: Montgomery, H. E.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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A precision measurement of the prompt photon cross section in p{bar p} collisions at {radical}s = 1.8 TeV

Description: A prompt photon cross section measurement from the CDF experiment at the Fermilab p{bar p} Collider is presented Detector and trigger upgrades, as well as six times the integrated luminosity compared with our previous publication, have contributed to a much more precise measurement and extended P{sub T} range. As before, the cross section agrees qualitatively with QCD calculations but has a steeper slope at low P{sub T}.
Date: June 1, 1994
Creator: Kuhlmann, S. E.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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The measurement of the W boson mass from CDF

Description: Recent results from LEP experiments have substantially improved the knowledge of the Z boson. However, hadron colliders remain the only source of direct measurements of the W boson. There have been measurements of the W boson mass from the UA2 and CDF collaborations. The W mass continues to be a subject of great interest in testing the Standard Model. Here, the authors have made a preliminary determination of the W boson mass M{sub W} = 80.38 {+-} 0.23 GeV/c{sup 2} from a combined analysis of W… more
Date: June 1, 1994
Creator: CDF Collaboration
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Search for supersymmetry and leptoquark states in D0

Description: Results are presented on the search for two types of exotic particles. First, a mass limit is given for first generation leptoquarks assuming pair production with the final state being either two electrons and two jets or one electron, a neutrino and two jets. This is followed by the presentation of a preliminary result on a search for the supersymmetric partners of the W{plus_minus} and Z{sup o}, the lightest chargino, W symmetry particle {sub 1}, and the second lightest neutralino, Z symmetry… more
Date: January 1994
Creator: White, James T.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Formation mechanism and yield of molecules ejected from ZnS, CdS, and FeS{sub 2} during ion bombardment

Description: Neutral species ejected from single crystals of ZnS, CdS, and FeS{sub 2} during ion bombardment by 3 keV Ar{sup +} were detected by laser post-ionization followed by time-of-flight mass spectrometry. While metal atoms (Fe, Zn, Cd) and S{sub 2} were the dominant species observed, substantial amounts of S, FeS, Zn{sub 2}, ZnS, Cd{sub 2}, and CdS were also detected. The experimental results demonstrate that molecules represent a larger fraction of the sputtered yield than was previously believed f… more
Date: March 1, 1994
Creator: Nikzad, S.; Calaway, W. F.; Pellin, M. J.; Young, C. E.; Gruen, D. M. & Tombrello, T. A.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Utility programs used for EPA Contract Laboratory Program computations

Description: Four computer programs were developed to manipulate GC/MS data and expedite both sample turnaround time and data package preparation for presentation of data following the EPA Contract Laboratory Program requirements. One program rapidly determines if the GC/MS daily standard has met QC criteria and therefore allows more samples to be analyzed within the 12-hour time limit. Another extracts total ion current for quantitation of tentatively identified compounds. The limit of detection is obtaine… more
Date: March 1, 1994
Creator: Hwang, E. Y. & Wingender, R. J.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Results from CERN experiment WA80

Description: Recent photon-measurement results are presented. Accurate reconstructed and {pi}{sup 0} and {eta} results have been obtained down to signal/noise ratios of 0.002. The production of {eta} mesons was found to be consistent with MT scaling observed in hadron-hadron collisions. ``Direct,`` single-photon yields were extracted from high-statistics S+Au data obtained at 200 GeV/nucleon. A slight excess of photons over the number of photons that can be accounted for by hadronic decays was observed for … more
Date: June 1, 1994
Creator: Collaboration, WA80
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Mass Spectrometry Studies of the Ionization of Organic Molecules by Slow Positrons

Description: The dissociative ionization of organic molecules, induced by positrons having energies below positronium thresholds (0.5--3 eV), has been studied. The ionization-fragmentation yields increase as positron energies decrease. The energies required for dissociative ionization are supplied by the annihilation processes. Fragmentation occurs by breakage of C-C single bonds in preference to double or triple bonds.
Date: June 1, 1994
Creator: Hulett, L. D. Jr.; Xu, Jun; Lewis, T. A.; Crawford, O. H. & McLuckey, S. A.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Excited Charm States

Description: Characteristics of mass spectra and decays of orbitally excited charm mesons and baryons, expected on the basis of quark models and Heavy Quark Symmetry, are briefly described. The difficulties associated with measurements on these excited states are discussed. The accuracy and reliability of currently available experimental information is examined. The reasons, for the widely accepted spin-parity assignments to the observed excited mesons and baryons, are stated. Finally, the experimental data… more
Date: November 1994
Creator: Shukla, Shekhar
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Lepton charge asymmetry from W decay and search for new gauge bosons at D0

Description: A measurement is described of the charge asymmetry in the pseudorapidity distribution of muons from W boson decay in proton- antiproton collisions at {radical}s = 1.8 TeV using the D0 detector. We also report on a search for extra gauge bosons in the electron decay channel. Mass limits of M{sub W}{prime} > 600 GeV and M{sub Z}{prime} > 440 GeV are obtained at 95% confidence level under the assumption of standard model couplings.
Date: January 1, 1994
Creator: Taketani, Atsushi
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Studies of kinematic distributions and mass reconstruction of CDF top candidate events

Description: We present analyses of CDF top-candidate events which study the separation of signal from background using easily-defined kinematic variables, and which study invariant masses of three-body systems to fully reconstruct the top quark decay products.
Date: August 1, 1994
Creator: Harral, B. D.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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A measurement of the mass of the W vector boson at CDF

Description: We present a preliminary measurement of the mass of the W vector boson using the decays W {yields} ev and W {yields} {mu}v. The mass of the W is an important parameter of the standard model. Through its relation to both the top quark and the higgs sector, it provides a sensitive probe of the electroweak theory. During the last run of Fermilab`s Tevatron, CDF recorded {bar p}p collisions at {radical}s = 1.8 TeV corresponding to an integrated luminosity of 19.3 pb{sup {minus}1}. An analysis of bo… more
Date: September 1, 1994
Creator: Keup, R. M.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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The diphoton production rate in {bar p}p collisions at {radical}s = 1800 GeV

Description: A measurement of the rate of prompt diphoton production in {bar p}p collisions at {radical}s = 1800 GeV using the CDF detector is presented. The background from non-prompt sources is estimated using a sample of single photon candidate events. The results are compared to a next-to-leading order calculation by Bailey, et al. Both background and signal take on particular significance as an indicator of our ability to estimate the backgrounds affecting LHC low mass Higgs to diphoton searches.
Date: August 1, 1994
Creator: Blair, R.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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B meson lifetimes at CDF

Description: Measurements of the B{sub u}, B{sub d}, and B{sub s} meson lifetime using semileptonic B{sub U} {yields} e{nu}D* X, B{sub s} {yields} l{nu}D{sub s}X events and exclusive B{sub u} {yields} {psi}({prime})K({sub s})(*)B{sub s} {yields} {psi}{phi} events are presented. These results used the precise position measurements of the CDF SVX silicon vertex detector and were obtained from a 19.3 pb{sup {minus}1} sample of 1.8 TeV {bar p}p collisions collected in 1992--93 at the Fermilab Tevatron collider.… more
Date: August 1, 1994
Creator: Skarha, J. E.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Measurement of W and Z boson production and extraction of the W width and branching ratios at CDF

Description: We present results from W and Z boson production in proton-antiproton collisions at {radical}s = 1.8 TeV using the CDF detector. We measure the W and Z cross sections times lepton branching ratio, {sigma}(p{bar p} {yields} W){center_dot}B(W {yields} l{nu}{sub l}) and {sigma}(p {bar p} {yields} Z){center_dot} B(Z {yields} k{sup +}l{sup {minus}}) l = e, {mu}. We also measure the ratio: R{sub l} = {sigma} {center_dot} B(W {yields} l{nu}{sub l})/{sigma} {center_dot} B(Z {yields} ll). From R{sub l},… more
Date: August 1, 1994
Creator: Badgett, W. F.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Search for Z{prime} and W{prime} at CDF

Description: We have searched for heavy neutral and charged gauge bosons via the decays Z{prime} {yields} ee and W{prime} e{nu} in {bar p}p collisions at {radical}s = 1.8 TeV. The data were obtained using the CDF detector during 1992--1993 run corresponding to an integrated luminosity of 19.7{plus_minus}0.7 pb{sup {minus}1}. We present a 95% confidence level upper limit on the production cross section times branching ratio of Z{prime} and W{prime} as a function of Z{prime} and W{prime} mass. Assuming Standa… more
Date: August 1994
Creator: Maeshima, Kaori
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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