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Neutrino magnetic moment

Description: We review attempts to achieve a large neutrino magnetic moment ({mu}{sub {nu}} {le} 10{sup {minus}11}{mu}{sub B}), while keeping neutrino light or massless. The application to the solar neutrino puzzle is discussed. 24 refs.
Date: January 1, 1990
Creator: Chang, D. (Northwestern Univ., Evanston, IL (USA). Dept. of Physics and Astronomy Fermi National Accelerator Lab., Batavia, IL (USA)) & Senjanovic, G. (Zagreb Univ. (Yugoslavia). Dept. of Theoretical Physics)
Partner: UNT Libraries Government Documents Department

On the electronics for Experiment E687's trigger on hadron momenta

Description: The purpose of this paper is to describe the electronic modules designed to process the E687 hadron calorimeter's 552 readout channels and generate a trigger signal based upon the total momentum and the total transverse momentum of the detected hadrons.
Date: July 1, 1990
Creator: Ramusino, A.C.; Hansen, S. (Fermi National Accelerator Lab., Batavia, IL (USA)) & Buchholz, D. (Northwestern Univ., Evanston, IL (USA))
Partner: UNT Libraries Government Documents Department

Multifractal structures in multiparticle production in p -p interactions at radical s = 1800 GeV

Description: Fractal structure in multiparticle production of {bar p} {minus} p minimum-bias'' interactions at {radical}s = 1800 GeV has been studied using the Collider Detector at Fermilab. Preliminary results are shown and compared with very simple Monte Carlo models.
Date: August 1, 1990
Creator: Rimondi, F. (Bologna Univ. (Italy) Istituto Nazionale di Fisica Nucleare, Bologna (Italy))
Partner: UNT Libraries Government Documents Department

Tests of full scale SSC (Superconducting Super Collider) R and D dipole magnets

Description: Four full-scale SSC R and D dipole magnets, incorporating successive mechanical design improvements, have been quench tested. Three of these magnets are heavily instrumented with sensors to measure the mechanical behavior of the magnets and verify the performance of the mechanical improvements and with multiple voltage taps to locate the origin of quenches. The last two magnets of this series reach the SSC design operating field of 6.6 T in two or fewer quenches. Load cells and motion sensors show that in these two magnets the azimuthal clamping stress is higher at zero current and drops more slowly with excitation than in previous long magnets and that the axial motion of the coil upon excitation has been greatly reduced. Quenches are found to originate preferentially in several locations, suggesting other design improvements. 13 refs., 5 figs.
Date: August 22, 1988
Creator: Strait, J.; Brown, B.C.; Hanft, R.; Kuchnir, M.; Lamm, M.; Lundy, R. et al.
Partner: UNT Libraries Government Documents Department

Calculation of tune vs amplitudes for the new low beta quadrupoles

Description: I calculate the tune as function of amplitude due to higher multipole errors (in particular the dodecapole) in the new low beta quadrupoles. The results indicate that these multipoles are not expected to give rise to serious problems for the next Tevatron Collide run with two interaction regions.
Date: July 18, 1990
Creator: Visnjic, V.V.
Partner: UNT Libraries Government Documents Department

Beam diagnostics in circular machines: Review of new developments

Description: Recent developments in beam diagnostic equipment and measurement techniques have been driven by commercial technological advances, better data analysis algorithms, and the need to measure complex beam properties. The need for such developments is due to the increased diversity, beam intensity, and luminosity/brightness requirements of charged particle circular accelerators. In addition, the advent of fast analog-to-digital converters and cheap, powerful microprocessors have fundamentally changed the approach to beam diagnosis, allowing designers to create systems where signal processing is performed locally at each detector. New beam monitors from a wide variety of circular accelerators are reviewed. A number of interesting or innovative ideas are presented in detail. 56 refs.
Date: June 1, 1990
Creator: Jackson, G.
Partner: UNT Libraries Government Documents Department

Flux creep in a TEVATRON cable

Description: We have measured the slow magnetization decay of a short sample (2.3 cm) of Tevatron cable in fields up to 0.3 T. The special susceptometer in development for these measurements is based on a commercial SQUID and is described in detail. The observed decay is logarithmic in time as expected from flux creep in the NbTi filaments. A strong correlation was found between the decay and the magnetization status of the sample. It is too early yet to present a quantitative correlation between what we observed and the decay observed in the sextupole component of Tevatron dipoles. The detailed understanding of this phenomenon may be instrumental in guiding the search for efficient superconducting synchrotron operational procedures. 3 refs., 5 figs.
Date: August 22, 1988
Creator: Kuchnir, M. & Tollestrup, A.V.
Partner: UNT Libraries Government Documents Department

Electron identification at CDF

Description: Electron identification at CDF is performed using the information of lateral and longitudinal shower spread, the track-cluster position match and the energy-momentum match. The tracking chamber with a solenoidal magnetic field at CDF is powerful for rejecting the backgrounds such as the {pi}{sup {plus minus}} {minus} {pi}{sup 0} overlaps, the {pi}{sup 0}/{gamma} conversions and interactive {pi}{sup {plus minus}} in electromagnetic calorimeter: The energy- momentum match cut can decrease the background due to the {pi}{sup {plus minus}} {minus} {pi}{sup 0} overlaps for non-isolated electrons with Et above 10 GeV by a factor of 20. The conversion electrons are identified using track information with an efficiency of 80 {plus minus} 3%. The charge of electrons from W decay can be determined in the pseudorapidity range of {vert bar}{eta}{vert bar} < 1.7 at CDF. The charge determination is useful for background estimation of Drell-Yan physics and heavy flavor physics. 5 refs., 5 figs.
Date: June 1, 1990
Creator: Kim, Shinhong (Tsukuba Univ., Ibaraki (Japan). Inst. of Physics)
Partner: UNT Libraries Government Documents Department

Mechanical support of superconducting coils

Description: Cold iron magnets use the iron yoke and skin for mechanical support of the collared coil assembly. A variety of designs, including horizontally and vertically split yokes, collarless'' magnets and conductor block geometries, have been considered for use with collared coils. This note qualitatively compares the support mechanisms by estimating the amount of coil overcompression'' necessary for the magnet to achieve the same mechanical condition in the cold, powdered state. These designs inspect magnet limitations by suggesting means to reduce the peak coil compressive load, allowing higher central magnetic fields to be reached.
Date: July 1, 1990
Creator: Bossert, R.C. & Kerby, J.S.
Partner: UNT Libraries Government Documents Department

Cooperative processes software (CPS)

Description: CPS is a package of software tools for splitting a computational task, called a job, among a set of processes distributed over one or more processors. It is designed to function as a tool for solving computing problems which require many computing cycles per I/O byte, and is well suited for computing platforms consisting of farms'' of processors, operating in parallel. This paper describes three essential features of CPS: data transfers between cooperating processes, remote subroutine calls, and process queues. 5 figs.
Date: April 1, 1990
Creator: Kaliher, C.
Partner: UNT Libraries Government Documents Department

SSC dipole magnet measurement and alignment using laser technology

Description: Advancing into the prototype production stage of the SSC dipole magnets has introduced the need for a reliable, readily available, accurate alignment measuring system which gives results in real time. Components and subassemblies such as the cold mass and vacuum vessel are being measured for various geometric conditions such as straightness and twist. Variations from nominal dimensions are also being recorded so they can be compensated for during the final assembly process. Precision laser alignment takes specific advantages of the greatest accuracy. When combined with an optically produced perpendicular plane, this results in a system of geometric references of unparalleled accuracy. This paper describes the geometric requirements for SSC dipole magnet components, sub and final assemblies as well as the use of laser technology for surveying as part of the assembly process.
Date: June 1, 1990
Creator: Lipski, A.; Carson, J.A. & Robotham, W.F.
Partner: UNT Libraries Government Documents Department

Fermilab Library projects

Description: Preprint database management as done at various centers -- the subject of this workshop -- is hard to separate from the overall activities of the particular center. We therefore present the wider context at the Fermilab Library into which preprint database management fits. The day-to-day activities of the Library aside, the dominant activity at present is that of the ongoing Fermilab Library Automation. A less dominant but relatively time-consuming activity is that of doing more online searches in commercial databases on behalf of laboratory staff and visitors. A related activity is that of exploring the benefits of end-user searching of similar sources as opposed to library staff searching of the same. The Library Automation Project, which began about two years ago, is about to go fully online.'' The rationale behind this project is described in the documents developed during the December 1988--February 1989 planning phase.
Date: May 3, 1990
Creator: Garrett, P. & Ritchie, D.
Partner: UNT Libraries Government Documents Department

Dynamical symmetry breaking of the electroweak interactions and the renormalization group

Description: We discuss dynamical symmetry breaking with an emphasis on the renormalization group as the key tool to obtaining reliable predictions. In particular we discuss the mechanism for breaking the electroweak interactions which relies upon the formation of condensates involving the conventional quarks and leptons. Such a scheme indicates that the top quark is heavy, greater than or of order 200 GeV, and gives further predictions for the Higgs boson mass. We also briefly describe recent attempts to incorporate a 4th generation in a more natural scheme. 13 refs., 3 figs., 1 tab.
Date: August 1, 1990
Creator: Hill, C.T.
Partner: UNT Libraries Government Documents Department

Semi-remote handling of radioactive devices in the Fermilab target stations

Description: Six additional, isolated, and self-contained target stations are being built as part of the upgrade of the three Fermilab fixed target Experimental Areas. One new system of shielding and semi-remote component handling via a crane is being developed for all of these. The first of these stations is under test. The system is simple and flexible. It successfully provides semi-remote handling of components from within the shielding of the stations.
Date: January 1, 1984
Creator: Eartly, D.; Currier, R.; Lindberg, J.; Sobczynski, S.; Stredde, H. & Strickland, W.
Partner: UNT Libraries Government Documents Department

Jet dynamics at the Tevatron collider

Description: Results for processes involving two or more hadronic jets at {radical}s = 1800 GeV are presented. The data are compared with the results predicted from perturbative QCD. 16 refs., 10 figs.
Date: December 1, 1989
Creator: Plunkett, R.
Partner: UNT Libraries Government Documents Department

Top quark and SUSY (supersymmetric) searches at CDF

Description: Searches for the top quark in p{bar p} collisions at {radical}s = 1.8 TeV are described. The analyses are based on data with an integrated luminosity of 4.4 pb{sup {minus}1} recorded with the Collider Detector at Fermilab in the 1988--1989 run. An upper limit on the t{bar t} cross section is obtained. The top quark with mass below 89 GeV/c{sup 2} is excluded at the 95% CL. Prospects for searches for the top quark in the future are presented. We also briefly present results on searches for supersymmetric particles. 14 refs., 10 figs.
Date: May 17, 1990
Creator: Yeh, G.P.
Partner: UNT Libraries Government Documents Department

Muon interactions at 490 GeV

Description: E665 is a new, high-energy muon scattering experiment at Fermilab. Data were taken with a 490 GeV muon beam incident on deuterium, hydrogen, and xenon targets during the 1987--88 fixed target run. These data are being analyzed with various physics objectives in mind, and a number of preliminary results have been obtained. This paper presents four of results, specifically the small {chi}{sub Bj} ratio of xenon and deuterium cross sections, inclusive hadron distributions, two jet signals, and exclusive {rho}{sup 0} production.
Date: June 1, 1990
Creator: Schmitt, M. (Fermi National Accelerator Lab., Batavia, IL (USA) Harvard Univ., Cambridge, MA (USA))
Partner: UNT Libraries Government Documents Department

Operation of a 2-phase return dewar in a satellite refrigerator

Description: In late 1986 a 100 liter liquid helium phase separator/dewar was designed for use in the Tevatron satellite refrigeration system. Installed on the low pressure return side of the helium circuit between the tunnel return and the exchanger cold end, this vessel was to provide phase separation for a future centrifugal cold compressor installed immediately downstream. Additionally, the vessel by itself would buffer the satellite refrigerator's coldbox from cryogenic system upsets occurring in the tunnel during Tevatron operation. By mid-1988 a prototype had been constructed and approval received to install the 2-phase return dewar in the A1 refrigerator. This paper describes both vessel and refrigerator performance during this test period and draws conclusions with regard to the benefits of such a device in a satellite refrigerator.
Date: August 1, 1990
Creator: Fuerst, J.D.
Partner: UNT Libraries Government Documents Department

Wide Band to ''Double Band'' upgrade

Description: The Wide Band beam currently uses electrons obtained from secondary photon conversions to produce the photon beam incident on the experimental targets. By transporting the positrons produced in these conversions as well as the electrons it is possible to almost double the number of photons delivered to the experiments per primary beam proton. 11 figs.
Date: June 1, 1988
Creator: Kasper, P.; Currier, R.; Garbincius, P. & Butler, J.
Partner: UNT Libraries Government Documents Department

Psi' photoproduction at a mean energy of 150 GeV

Description: A measurement of the diffractive psi' photoproduction cross section is presented. The ratio of the psi' photoproduction cross section to the psi photoproduction cross section is found to be 0.20 +- 0.05 at an average energy of 150 GeV. Using vector meson dominance, the ratio of psi'-nucleon to psi-nucleon cross sections is 0.75 +- 0.12.
Date: November 1, 1982
Creator: Binkley, M.; Butler, J. & Cumalat, J.
Partner: UNT Libraries Government Documents Department

Quantum chromodynamics (QCD) and collider physics

Description: This report discusses: fundamentals of perturbative QCD; QCD in e{sup +}e{sup {minus}} {yields} hadrons; deep inelastic scattering and parton distributions; the QCD parton model in hadron-hadron collisions; large p{sub T} jet production in hadron-hadron collisions; the production of vector bosons in hadronic collisions; and the production of heavy quarks.
Date: August 14, 1990
Creator: Ellis, R.K. (Fermi National Accelerator Lab., Batavia, IL (USA)) & Stirling, W.J. (Durham Univ. (UK))
Partner: UNT Libraries Government Documents Department

An experimental study of the SSC (Superconducting Super Collider) magnet aperture criterion

Description: A beam dynamics experiment, performed in the Fermilab Tevatron, that was mainly motivated by planning for the Superconducting Super Collider (SSC) is described. Nonlinearities are introduced in the Tevatron by special sextupoles in order to stimulate the SSC environment. ''Smear'' is one of the parameters used to characterize the deviation from linear behavior. Smear is extracted from experimental data and compared with calculation over a wide range of conditions. The agreement is excellent. The closed orbit at injection trajectory reveal no deterioration even at the highest sextupole excitations. Measurements of the dynamic aperture are in general agreement with prediction. Particles captured on nonlinear resonance islands are directly observed and measurements are performed for the first time. The stability of the islands under tune modulation is investigated. 4 refs., 8 figs.
Date: June 7, 1988
Creator: Merminga, N.; Edwards, D.; Finley, D.; Gerig, R.; Gelfand, N.; Harrison, M. et al.
Partner: UNT Libraries Government Documents Department

Assuring both quality and creativity in basic research

Description: How does one assure that both quality and creativity are obtained in basic research environments QA theoreticians have attempted to develop workable definitions of quality, but in more reflective moments, these definitions often fail to capture the deeper essence of the idea of quality.'' This paper asserts that creativity (as a product of the human mind) is a concrete interface between perfunctory definitions of quality (conformance to specifications) and more philosophical speculations about the nature of quality- related ultimates'' like elegance or beauty. In addition, we describe the distinction between creative ideas and creative acts and highlight one of the major inhibitors of creativity, fear. Finally we show that highly creative people often have an irreverent attitude toward boundaries and established authority, and discuss how one can allow for this when designing a QA program in a basic research environment.
Date: April 12, 1990
Creator: Bodnarczuk, M.
Partner: UNT Libraries Government Documents Department