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Fermilab Physics Program for the 1990's

Description: Following a brief introduction to Fermilab facilities and a review of the accelerator status and plans, the physics potential for the Fermilab III upgrade program is discussed for both the fixed target and collider modes.
Date: October 15, 1990
Creator: Stanfield, K.C.
Partner: UNT Libraries Government Documents Department

QCD tests at CDF

Description: Recent analysis of jet data taken at the Fermilab Tevatron Collider at {radical}S = 1.8 Tev are presented. Inclusive jet, dijet, trijet and direct photon measurements are compared to QCD parton level calculations, at orders {alpha}{sub s}{sup 3} or {alpha}{sub s}{sup 2}. The large total transverse energy events are well described by the Herwig shower Montecarlo. 19 refs., 20 figs., 1 tab.
Date: May 1, 1991
Creator: Giannetti, P. (Istituto Nazionale di Fisica Nucleare, Pisa (Italy))
Partner: UNT Libraries Government Documents Department

Search for the top quark with CDF

Description: During the 1988--89 Tevatron Collider run the CDF detector has collected data for an integrated luminosity of 4.4 pb{sup {minus}1}. The sample has been used to search for the top quark in several topologies. Preliminary results show that a top mass below 89 GeV is excluded at the 95% confidence level, thus extending the limit of 77 GeV previously published by CDF. 14 refs., 8 figs.
Date: January 22, 1991
Creator: Barbaro-Galtieri, A. (Lawrence Berkeley Lab., CA (USA))
Partner: UNT Libraries Government Documents Department

Results from E735 at the Tevatron proton-antiproton collider with radical s = 1. 8 TeV

Description: Experiment E735{dagger} searched for evidence of the transition to quark-gluon plasma in p{bar p} collisions at {radical}{bar s} = 1.8 TeV. Using data from a high statistics run in 1988--1989, results are presented on multiplicity distributions, hyperon and phi production, and Bose-Einstein correlations. Some data was also taken at lower collision energies and results will be compared to previous experiments.
Date: November 1, 1991
Creator: Lindsey, C.
Partner: UNT Libraries Government Documents Department

CDF: Recent results and future prospects

Description: We present recent results from the Collider Detector at Fermilab. Searches for the top quark have established a lower bound of M{sub top} > 91 GeV/c{sup 2} (at 95% confidence level). A measurement of B{sup o}{bar B}{sup o} mixing has been obtained from b{bar b} {yields} e{mu}, ee events. Measurements of b-quark production have been obtained from e + X events and J/{psi} + K events. The mass of the W boson has been determined to be M{sub W} = 79.91 {plus minus} 0.39 GeV/c{sup 2}. In searching for new gauge bosons, we have obtained the bounds M{sub Z{prime}} > 412 GeV/c{sup 2} and M{sub W{prime}} > 520 GeV/c{sup 2} (at 95% C.L.). The lower limits on the quark and lepton compositeness scales are 1.4 TeV. In the next two years of data collection, we expect significantly more events for numerous types of physics, due to 25 times more beam luminosity, and improvement to the detector. In the longer term, the Main Injector'' upgrade to the accelerator, further improvements to the detector are being planned to exploit the potentials for physics. We discuss prospects for the discovery of the top quark, precise measurement of properties of b quark, and searches for new physics beyond the Standard Model. 29 refs.
Date: March 3, 1992
Creator: Yeh, G.P.
Partner: UNT Libraries Government Documents Department

A missing transverse energy analysis of 1. 8 TeV /bar p/-p collisions observed at CDF

Description: We summarize a missing transverse energy analysis of 25.3 nb/sup /minus/1/ of /bar p/-p collision data taken with the CDF detector during its 1987 run. With this analysis we excluded supersymmetric squarks of mass less than 73 GeV, and supersymmetric gluinos of mass less than 74 GeV at the 90% CL. We then present a preliminary missing transverse energy analysis of 1 pb/sup /minus/1/ of proton-antiproton collision data at c.m. energy of 1.8 TeV observed by the CDF detector during the 1988--1989 Tevatron Collider run. The distribution of events with large missing transverse energy is again found to be consistent with Standard Model expectations. The absence of an excess of events with large missing transverse energy in this preliminary analysis suggests that in the simplest supersymmetry scenario, the existence of supersymmetric squarks of mass less than 150 GeV is unlikely. 6 refs., 6 figs., 3 tabs.
Date: June 1, 1989
Partner: UNT Libraries Government Documents Department

Vertex detection at the Tevatron

Description: Addition of vertex detectors to CDF and D0 will facilitate a rich program of beauty physics at the Tevatron, and may enable tags of B and {tau} which facilitate searches for top and other heavy objects. We also address the operational considerations of triggering and radiation protection, and speculate on possible directions for upgrades. 9 refs., 7 figs.
Date: January 11, 1991
Creator: Amidei, D. (Michigan Univ., Ann Arbor, MI (USA)); Shepard, P. (Pittsburgh Univ., PA (USA)) & Tkaczyk, S. (Fermi National Accelerator Lab., Batavia, IL (USA))
Partner: UNT Libraries Government Documents Department

B-physics at CDF and prospects for the next run

Description: Current CDF b-physics results are presented. The analysis is based on data corresponding to an integrated luminosity of 4.4 pb{sup {minus}1} recorded with the CDF detector in 88--89 at the Fermilab Tevatron p{bar p} collider ({radical}{bar s} = 1.8 TeV). Preliminary results include the differential cross section {sub dPt}/{sup d{sigma}(b)}, some reconstructed exclusive B-decays, a limit for the rare decay B{sup 0} {yields} {mu}{sup +} {mu}{sup {minus}} and a measurement of B{bar B}-mixing parameters. Finally we will discuss the prospects concerning b-physics for the next data run which will start in February 1992. 12 refs., 8 figs.
Date: September 1, 1991
Creator: Wenzel, H. (Istituto Nazionale di Fisica Nucleare, Pisa (Italy))
Partner: UNT Libraries Government Documents Department

Jets in CDF

Description: In the 1988/89 Tevatron Collider run the CDF experiment collected 4.0 {plus minus} 0.3 pb{sup {minus}1} of proton-antiproton interactions at a center-of-mass collision energy currently available in the laboratory and gives us a unique opportunity for studying Quantum Chromodymanics (QCD) processes at the highest available energies. We report results from various QCD studies performed with this data. 11 refs., 8 figs.
Date: July 1, 1991
Creator: Buckley-Geer, E. (Rutgers--the State Univ., New Brunswick, NJ (United States))
Partner: UNT Libraries Government Documents Department

The High-Energy Transport Code HETC88

Description: An upgraded version, HETC88, of the previously available High-Energy Transport Code HETC is briefly described. In the upgraded code, the particle production model from hadron-nucleus nonelastic collisions at energies greater than 5 GeV has been revised. At nucleon and ion energies below 5 GeV, HETC88 is not different from the code previously available. In particular, provision is still made to allow neutrons with energies less than or equal to20 MeV to be transported by none of the available codes designed for low-energy neutron transport. Calculated results for the longitudinal distribution of the flux of neutrons with energy greater than or equal to40 KeV in the Tevatron tunnel when 900 GeV protons interact with N/sub 2/ in a warm section are presented and compared with experimental data. Some disagreements between the calculated and measured neutron flux are found. For 20 TeV protons incident on a large cylindrical iron target, calculated ''star'' density results from HETC88, FLUKA87, CASIM, and MARS10 are also compared. 22 refs., 3 figs.
Date: January 1, 1989
Creator: Alsmiller, R.G. Jr.; Alsmiller, F.S.; Gabriel, T.A.; Hermann, O.W. & Barnes, J.M.
Partner: UNT Libraries Government Documents Department

New Main Ring control system

Description: The Fermilab Main Ring control system has been operational for over sixteen years. Aging and obsolescence of the equipment make the maintenance difficult. Since the advent of the Tevatron, considerable upgrades have been made to the controls of all the Fermilab accelerators except the Main Ring. Modernization of the equipment and standardization of the hardware and software have thus become inevitable. The Tevatron CAMAC serial system has been chosen as a basic foundation in order to make the Main Ring control system compatible with the rest of the accelerator complex. New hardware pieces including intelligent CAMAC modules have been designed to satisfy unique requirements. Fiber optic cable and repeaters have been installed in order to accommodate new channel requirements onto the already saturated communication medium system. 8 refs., 2 figs.
Date: March 1, 1990
Creator: Seino, K.; Anderson, L.; Ducar, R.; Franck, A.; Gomilar, J.; Hendricks, B. et al.
Partner: UNT Libraries Government Documents Department

Progress report of a research program in experimental high energy physics

Description: An experimental program in strong and electro-weak interaction physics of elementary particles is being carried out using electronic detection techniques. Experiments have been performed at Brown, Brookhaven, and Fermilab. The work described in this report by the Electronic Detector Group addresses the following: neutrino interactions and intrinsic properties, preparations for experiments ( D--ZERO'') at the FNAL 2 TeV {bar p}p Collider, new detection techniques for neutrino properties.
Date: July 1, 1990
Creator: Lanou, R.E. Jr. & Cutts, D.
Partner: UNT Libraries Government Documents Department

Report of the Electroweak Interactions Theoretical Issues Working Group

Description: An interesting component of the physics program at Fermilab during the next ten years will be the precision verification of the standard model, rather than its extension. While there is a window for finding Z{prime} gauge bosons, it is unlikely that it is possible to discover the standard model Higgs boson. Measurements of W + {gamma} rates can place limits on non-standard gauge boson couplings. QCD will be further tested by observation of W or Z plus multiple jets, a signal which is also interesting as a background to new particle searches. Precision measurements of the W and Z masses and the forward-backward asymmetry in Z decays can put limits on new physics. 26 refs., 1 fig., 2 tabs.
Date: November 1, 1989
Creator: Golden, M.
Partner: UNT Libraries Government Documents Department

Simulation of top quark production at D0

Description: The production of top at the Fermilab Tevatron D0 detector was investigated using full Monte Carlo and event reconstruction packages. In total, 480 events were generated for m{sub T} = 150 GeV/c{sup 2} in the specific t({bar t}) {yields} b({bar b}) + W{sup {plus minus}}, with at least one W decaying to leptons. These events were then analyzed in an attempt to find characteristic signals for top production at D0. 21 figs.
Date: May 12, 1990
Creator: Barter, C.M.
Partner: UNT Libraries Government Documents Department

Tevatron Collider physics

Description: The physics of hadron colliders is briefly reviewed. Issues for further study are presented. Particular attention is given to the physics opportunities for a high luminosity ({ge} 100 pb{sup {minus}1}/experiment/run) Upgrade of the Tevatron Collider. 25 refs., 10 figs., 2 tabs.
Date: February 1, 1990
Creator: Eichten, E.J.
Partner: UNT Libraries Government Documents Department

Motion control of the accumulator flying wires

Description: Flying wire systems for the Fermilab Accumulator are being constructed in order to measure the transverse beam profiles during stacking. Each device passes a 25 micron carbon filament through the beam transversely at a constant velocity of 10 m/s. Collisions between the beam particles and the wire produce secondary particle cascades, which in turn produce photons in a scintillator. A photomultiplier tube is used to measure the light intensity while the wire position is determined by an optical encoder. There are six Accumulator flying wire systems. Four of them are to be used in normal stacking operation: two horizontal and two vertical flying wires are in the AP40 high dispersion section, covering the core orbit and the extraction orbit respectively. The other two horizontal wires are for measuring the momentum distribution of the beam on the central orbit at the Accumulator transition energy. At the AP40 high dispersion region a wire covers the central orbit, the other is in the AP30 low dispersion section. The operation and control of the flying wire system is discussed in this paper. 11 figs.
Date: April 23, 1990
Creator: Wang, X.Q.
Partner: UNT Libraries Government Documents Department

Small t physics at the Tevatron Collider

Description: The first physics run of the superconducting Tevatron Collider at Fermilab ended this morning. A status report will be presented on the progress of the small angle elastic scattering and total cross section experiment, E710. The goals of this experiment are to measure the total proton-antiproton cross section from ..sqrt..s = 300 to 2000 GeV, the slope of the diffraction peak and rho, the ratio of the real to imaginary part of the forward scattering amplitude, at these energies. 1 ref., 8 figs.
Date: May 11, 1987
Creator: Bertani, M.; Giacomalli, G.; Maleyran, R.; Manarin, A.; Amos, N.; DeSalvo, R. et al.
Partner: UNT Libraries Government Documents Department

Current results from CDF on W, Z, and top

Description: Results based on data collected by the Collider Detector at Fermilab (CDF) during the Tevatron Collider run now in progress are presented. The results cover analyses of W {yields} e{nu}{sub e} and Z {yields} e{sup +}e{sup {minus}}, {mu}{sup +}{mu}{sup {minus}} event candidates, and discuss the status of the CDF top quark search. Preliminary results from studies of events containing a high E{sub T} electron and muon or a high E{sub T} electron plus {ge} 2 jets indicate that it is unlikely that the top quark mass is in the range 30 {le} M {sub top} {le} 60 GeV/c{sup 2} assuming Standard Model charged current decay. 4 refs., 13 figs.
Date: January 1, 1989
Creator: Wagner, R.G.
Partner: UNT Libraries Government Documents Department

Jets, W's, and Z's at radical s = 1. 8 TeV

Description: Jet production and electroweak vector boson production have been observed in proton-antiproton collisions at the Fermilab Tevatron Collider. The inclusive jet cross section has been measured for jets up to transverse energies of 400 GeV, and is compared to QCD predictions. W and Z particle production has been observed and studies of their masses are described. 3 refs., 4 figs.
Date: January 1, 1989
Creator: Kuhlmann, S.E. (Argonne National Lab., IL (USA))
Partner: UNT Libraries Government Documents Department

The W boson transverse momentum spectrum in proton-antiproton collisions at radical s = 1. 8 TeV

Description: The Collider Detector at Fermilab (CDF) was used to measure the transverse momentum distribution of W boson produced in proton-antiproton collisions at the Tevatron collider. The W bosons were identified by the decay W {yields} e{nu}. The results are in good agreement with a next-to-leading order calculation. The cross section for W production with P{sub T} > 50 GeV/c is 423 {plus minus} 58 (stat.) {plus minus} 108 (sys.) pb. 58 refs., 53 figs., 16 tabs.
Date: February 1, 1991
Creator: Winer, B.L.
Partner: UNT Libraries Government Documents Department

Inclusive single muons at D0

Description: We report preliminary results on b-quark production in p[bar p] collisions at [radical]s = 1.8 TeV from the current Run la of the Tevatron collider. Using an inclusive muon data sample which corresponds to an integrated luminosity of 50--70 nb[sup [minus]1] and by further requiring the muon to be accompanied by a jet we obtain an almost background free sample of muons consistent with b[bar b] [yields] [mu]X decay. A preliminary p[sub T][sup [mu]] spectrum and some characteristics of this decay, compared to the Monte Carlo expectations, are presented.
Date: November 1, 1992
Creator: Bazizi, K.A. (California Univ., Riverside, CA (United States))
Partner: UNT Libraries Government Documents Department

First W decays observed with the D0 detector

Description: We have observed the first few W decays into electrons at the Tevatron, using the newly commissioned D0 detector. Preliminary results are presented. The number of observed decays as well as the transverse momentum of the electron, the neutrino and their transverse mass distributions, are consistent with expectations.
Date: October 1, 1992
Creator: Gobbi, B. (Northwestern Univ., Evanston, IL (United States). Dept. of Physics and Astronomy)
Partner: UNT Libraries Government Documents Department

Highlights from CDF

Description: After a hiatus of 3 years, CDF is again taking data. Many of the upgrades made to the detector during this period are described here, along with some preliminary indications of their performance. A brief survey of the new data is presented. Prospects for the current run are discussed.
Date: November 1, 1992
Creator: Yagil, A.
Partner: UNT Libraries Government Documents Department