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Highlights of B physics at CDF

Description: The CDF experiment at the Fermilab Tevatron collider has produced many B physics results. Recent measurements on B meson masses, B lifetimes, B branching ratios, limits on rare B decays, and B flavour tagging studies are reviewed.
Date: August 1, 1995
Creator: Paulini, M.
Partner: UNT Libraries Government Documents Department

Measurement of the B{sup +} and B{sup 0} meson lifetimes using exclusive B {yields} {psi}K decays at CDF

Description: The authors present recent CDF measurements of {tau}{sup +}, {tau}{sup 0}, and {tau}{sup +}/{tau}{sup 0} using exclusive B {yields} {psi}K decays, where B = B{sup +} or B{sup 0}, {psi} = J/{psi} or {psi}(2S), and K = K{sup +}, K*(892){sup 0}, K{sub S}{sup 0}, or K*(892){sup +}. The precision of these results is less than 10% and is nearly identical to that previously reported at LEP.
Date: July 1995
Creator: Abe, F.
Partner: UNT Libraries Government Documents Department

Search for new phenomena in CDF-I: Z{prime}, W{prime} and leptoquarks

Description: We present the latest results of CDF searches for Z{prime}, W{prime} and leptoquarks. Using about 70pb{sup -1} data from 1992-95 CDF runs, we have searched for Z{prime} {yields} l{sup +}l{sup -}, W{prime} {yields} WZ and pairs of second generation scalar leptoquark, S{sub 2}. We find no evidence for these new particles, and set new mass limits at 95% CL. We exclude M{sub Z{prime}} < 650 GeV/c{sup 2}, 205 < M{prime}{sub W} < 400 GeV/c{sup 2}, and M{sub S2} < 180 GeV/c{sup 2} for {beta} = 1 and M{sub S2} < 141 GeV/c{sup 2} for {beta} = 0.5. Two interesting strange events are also shown.
Date: July 1, 1995
Creator: Park, S.
Partner: UNT Libraries Government Documents Department

HTS wire irradiation test with 8 GeV protons

Description: The radiation level at High Energy Particle Accelerators (HEPA) is relatively high. Any active component which should be close to the accelerator has to be radiation hard. Since High Temperature Superconductors (HTS) have a great potential to be used in HEPAs (e.g., in superconducting magnets, current leads, RF cavities), it is important to understand the radiation hardness of these materials. A radiation test of HTS wire (Bi-2223) was performed at Fermilab. The HTS sample was irradiated with 8 GeV protons and the relative I{sub c} was measured during the irradiation. The total radiation dose was 10 Mrad, and no I{sub c} degradation was observed.
Date: November 2, 1999
Creator: Feher, S.; Glass, H.; Huang, Y.; Limon, P.J.; Orris, D.F.; Schlabach, P. et al.
Partner: UNT Libraries Government Documents Department

Measurement of the CP violation parameter sin(2{beta}) in B{sup 0} {r_arrow}J/{psi} K{sub s}{sup 0} Decays

Description: A sample of {approximately} 400 B{sub d}{sup 0}/{bar B}{sub d}{sup 0} {r_arrow} J/{psi}K{sub s}{sup 0} decays collected in {bar p}p collisions by the CDF detector is used to directly measure the CP-violation parameter sin (2{beta}). They find sin(2{beta}) = 0.79{sub {minus}0.44}{sup + 0.41}, favoring the standard model expectation of a large CP violation in this B{sup 0} decay mode.
Date: September 2, 1999
Creator: Bauer, G.
Partner: UNT Libraries Government Documents Department

Results on Fermilab main injector dipole measurements

Description: Measurements of the Productions run of Fermilab Main Injector Dipole magnets is underway. Redundant strength measurements provide a set of data which one can fit to mechanical and magnetic properties of the assembly. Plots of the field contribution from the steel supplement the usual plots of transfer function (B/I) vs. I in providing insight into the measured results.
Date: June 1, 1995
Creator: Brown, B.C.; Baiod, R.; DiMarco, J.; Glass, H.D.; Harding, D.J.; Martin, P.S. et al.
Partner: UNT Libraries Government Documents Department

Fermilab central mass storage system as a test bed for HPSS

Description: Fermilab Central Mass Storage System (FCMSS) provides mass storage related services to 16 groups of users, mainly Fermilab Fixed Target Experiments. FCMSS is also used as a test bed for High Performance Storage System (HPSS). We report on our more than a year and a half long production experience of using HPSS and show results of various performance tests.
Date: December 1, 1998
Creator: Krzysztof Genser, Alexander Moibenko, Don Petravick, David Sachs and Joseph Syu
Partner: UNT Libraries Government Documents Department

Field shape of the accumulator LDA dipoles

Description: Large Aperture Dipoles (LDA) are used in the Fermilab Antiproton Accumulator to provide one half of the bending required for that storage ring. The production measurement data for those magnets are analyzed and the integrated field shape on the median plane at the design operating current (1,180 A) is reported. When linear (quadrupole) and parabolic (sextupole) terms are subtracted, the remaining field errors are only {approximately}10{sup {minus}4} over a {+-}4 inch aperture. Polynomial fits to that data can be interpreted in terms of normal harmonics of the magnetic field. However the polynomial fits are not unique. When the polynomial coefficients are expressed as harmonics with a reference radius of 1 inch, the nonlinear portions of this field (harmonics higher than quadrupole) are typically 10{sup {minus}5} to 10{sup {minus}6}. Both individual magnet results and statistical profiles are reported along with studies of the fitting limitations.
Date: May 1, 1996
Creator: Brown, B.C.
Partner: UNT Libraries Government Documents Department

Introduction to collective instabilities----longitudinal and transverse

Description: These topics are covered: 1 Wakes and impedances 1.1 Wake functions 1.2 Coupling impedances 2 Longitudinal phase space 2.1 Equations of motion 2.2 Vlasov equation 3 Potential-well distortion 4 Longitudinal microwave instability 4.1 Dispersion relation 4.2 Landau damping 4.3 Self-bunching 4.4 Overshoot and bunch lengthening 4.5 Observation 5 Longitudinal coupled-bunch instabilities 5.1 Sacherer integral equation 5.2 Time domain 5.3 Rf-detuning and Robinson's stability criteria 6 Transverse instabilities 6.1 Sacherer integral equation 6.2 Solution of Sacherer integral equations 6.1 Sacherer sinusoidal modes of excitation 6.2 Chromaticity frequency shift 7 Transverse coupled-bunch instabilities 7.1 Resistive wall 7.2 Narrow resonances 8 Head-tail instabilities 9 Mode-mixing 9.1 Transverse 9.2 Longitudinal. Exercises are included.
Date: October 1, 1998
Creator: Ng, King-Yuen
Partner: UNT Libraries Government Documents Department

Measurement of the hybrid photodiode response - Fiber optic window

Description: The hybrid photodiode (HPD[1]) will be used for the CMS HCAL readout [2]. A fiber-optic front window is used to reduce optical cross-talk between the pixels of the multi-pixel HPD�s. A mismatch of numerical aperture between optical fibers carrying light to the HPD window and the fibers composing the fiber-optic front window of the HPD could lead to light loss. The light loss would appear as a reduced effective quantum efficiency of the device. The goal of this set of measurements was to see if there was in fact a reduction in the effective quantum efficiency of the HPD�s.
Date: January 1, 1999
Creator: Ronzhin, A.; Green, D.; Freeman, J. & Barbaro, P. de
Partner: UNT Libraries Government Documents Department

Overview of coupled bunch active damper systems at FNAL

Description: Beam intensities in all of the accelerators at Fermilab will increase significantly when the Main Injector becomes operational and will cause unstable oscillations in transverse position and energy. Places where the coupled bunch oscillations could dilute emittances include the Booster, Main Injector, and Tevatron. This paper provides an overview of the active feedback system upgrades which will be used to counteract the problem. It will explain the similarities between all the systems and will also explain design differences between longitudinal and transverse systems, fast sweeping systems, and systems for partially filled machines. Results from operational systems will also be shown. 7 refs., 4 figs., 1 tab.
Date: May 1, 1996
Creator: Steimel, J.; Crisp, J.; Ma, Hengjie; Marriner, J. & McGinnis, D.
Partner: UNT Libraries Government Documents Department

Control system for Fermilab`s low temperature upgrade

Description: Fermilab recently upgraded the Tevatron Cryogenic Systems to allow for lower temperature operation. This Lower Temperature Upgrade grew out of a desire to increase the Colliding Beam Physics energy from 900 GeV to 1000 GeV. A key element in achieving this goal is the new cryogenic control system designed at Fermilab and installed in 24 satellite refrigerators and 8 compressor buildings. The cryogenic improvements and addition hardware like cold compressors exceeded the capability of the original distributed controls package. The new distributed controls package uses a Multibus II platform and Intel`s 80386 microprocessor. Token Ring is used as the link to the systems 6 primary crate locations with Arcnet used as the connection to the systems numerous I/O crates. I/0 capabilities are double the capabilities of the original system. Software has also been upgraded with the introduction of more flexible control loop strategies and Finite State Machines used for automatic sequential control, like quench recovery or cold compressor pump down.
Date: September 1, 1996
Creator: Norris, B.L.
Partner: UNT Libraries Government Documents Department

Upgrade plans for the D0 calorimeter

Description: The D{null} detector, a large collider detector located at the Fermi National Accelerator Laboratory, has begun implementing a major detector upgrade in anticipation of the completion of the Main Injector project at the Fermilab Tevatron. The calorimeter readout has been redesigned in order to accommodate the factor of {approx} 10 increase in instantaneous luminosity and the decrease in the inter- bunch separation. Our means of dealing with the increased event rate, along with our plan for controlling overall noise levels in the calorimeter, are discussed. We also present a brief overview of the design for the detector upgrade, including a discussion of some on the more cogent physics topics that will be accessible with the factor of {approx} 20 increase over the present data sample.
Date: August 1, 1996
Creator: Kotcher, J.
Partner: UNT Libraries Government Documents Department

Hadronic Calibration of D0 Calorimetry

Description: The D{null} detector is used to study {ital p{anti p}} collisions at the 1.8 TeV center-of-momentum energies available at the Fermilab Tevatron. The heart of the detector is a hermetic calorimeter employing uranium absorber and liquid argon as the ionization sampling medium. Several analyses require a well-understood jet energy scale. This paper describes how this calibration is obtained.
Date: September 1, 1996
Creator: Kehoe, R.
Partner: UNT Libraries Government Documents Department

The pixel microtelescope

Description: We describe a vertex and/or tracking detector designed to operate in an environment in which there is a large density of background hits. 2 refs., 2 figs.
Date: October 1, 1996
Creator: Chapman, J. & Geer, S.
Partner: UNT Libraries Government Documents Department

Searches for supersymmetry and Higgs particles with D-Zero

Description: We report on searches for the Supersymmetric and the neutral scalar particles with the D{null} detector at {radical}{ital s} = 1.8 TeV. The three searches that we report here are: (1) SUGRA motivated SUSY search, (2) search for Charginos and neutralinos, and (3) search for heavy neutral scalar particle produced in association with W bosons.
Date: November 1, 1996
Creator: Mondai, N. K.
Partner: UNT Libraries Government Documents Department

Experience with small turbomachinery in a 400 watt refrigerator

Description: A refrigerator similar to one of the Fermilab Tevatron satellites was reconfigured to use turbomachinery instead of the reciprocating equipment typical of the installations. A Sulzer dry turboexpander, Creare wet turboexpander, and IHI centrifugal cold compressor have been installed and operated for about 8000 hours. Experience was gained both with the rotating machinery and with the refrigerator itself as it interfaced with the load. Equipment was set up to regulate in the same manner as the reciprocating devices had. Heat load and operating mode were adjusted and evaluations made regarding the behavior of the devices. Individual equipment performance is described as well as system behavior and overall integration of the machinery. In particular, attention is paid to the Creare wet turboexpander. This device is operated for the first time as part of a full scale refrigeration system, testing not only its performance at the design point but also its off design characteristics and behavior in transient situations.
Date: September 1, 1996
Creator: Fuerst, J.D.
Partner: UNT Libraries Government Documents Department

Search for double parton scattering in the 4 jet channel at D0

Description: We have searched for double parton scattering in the 4-jet channel with an integrated luminosity of 4.4 pb{sup -1}, collected using the D{O} detector during 1994-1995 Fermilab Collider run at a center of mass energy ({radical}s) of 1.8 TeV. We present the preliminary observation of a statistically significant excess of signal.
Date: September 1, 1996
Creator: Yu, Yeonsik
Partner: UNT Libraries Government Documents Department

Study of the WW{gamma} and WWZ interactions at D0

Description: The {ital WW}{gamma} and {ital WWZ} gauge boson couplings have been studied through the direct observation of diboson final states produced in {ital p}{ital {anti p}} collisions at {radical}s = 1.8 TeV. The total cross section for {ital W}{sub {gamma}} final states, for photons with {ital p}{sub T}{sup {gamma}} {gt} 10 GeV/c and {ital R}{sub {ital l}{gamma}} {gt} 0.7, times branching ratio of {ital W} bosons to leptons, has been measured to be 12.10{sub -1.62}{sup +1. 76}{+-}1.72 pb, in agreement with the Standard Model expectation. An upper limit of 17 pb on the total {ital WW} cross section has been set. The analysis of {ital W}{sub {gamma}} events has allowed us to set 95% confidence level (CL) limits on the anomalous {ital WW}{sub {gamma}} coupling parameters of -0.96 {lt} {Delta}{kappa} {lt} 0.98 and -0.32 {lt} {lambda} {lt} 0.30. this measurement excludes the U(1){sub EM}- only coupling between the photon and the {ital W} boson at the 96% CL. Similar measurements of the coupling parameters have been performed using {ital WW} final states.
Date: August 1, 1996
Creator: Kelly, M.L. & Collaboration, DO
Partner: UNT Libraries Government Documents Department

D0 papers on B-physics submitted to DPF '96: b-quark inclusive cross sections and b anti-b correlations using dimuons from the D0 experiment; Single muon production in the forward region at {radical}s=1.8 TEV; Rapidity dependence of the inclusive J{psi} production in the forward region {radical}s=1.8 TEV; A search for b {r_arrow} X{mu}{sup +}{mu}{sup {minus}} and B{sup 0} {r_arrow} {mu}{sup +}{mu}{sup {minus}} decays in p anti-p collisions at {radical}s=1.8 TEV

Description: Paper 1: Using dimuons collected with the D0 detector during the 1993--1995 Tevatron collider run, the authors have measured the b-quark cross section and b{anti b} correlations as given by the difference in azimuthal angle between the two muons. Both measurements agree with the NLO QCD predictions within experimental and theoretical errors. (Three other papers are included in this report.)
Date: November 1996
Creator: Vititoe, D. L.; Kozelov, Alexander; Jesik, Richard & Collaboration, D0
Partner: UNT Libraries Government Documents Department