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A study of tau decays of the W boson at CDF (Collider Detector at Fermilab)

Description: A report is given of a search for tau decays of the W boson in p{bar p} collisions at {radical}s = 1.8 TeV using the Collider Detector at Fermilab (CDF). A description of a hardware trigger specifically designed to enhance the number of events with tau decays is presented along with the results of a preliminary analysis of data taken during the 1988--89 run of CDF. 10 refs., 4 figs.
Date: January 3, 1990
Creator: Gladney, L. D.
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Partner: UNT Libraries Government Documents Department
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Pseudorapidity densities and fluctuations in central sup 32 S interactions at 200A GeV

Description: Observations of heavy ion interactions at the highest available accelerator energies provide essential information for the analysis and interpretation of cosmic ray interactions. We report on an experiment in which emulsion chamber detectors were exposed to beams of 200A GeV {sup 32}S ions at the CERN SPS. We present statistical features of pseudorapidity distributions from central collisions in the experimental sample and compare them with the predictions from the Lund Model (FRITIOF) which co… more
Date: January 1, 1990
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Partner: UNT Libraries Government Documents Department
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Thermally Induced Structural Changes in Coal Combustion

Description: The effect of particle shape on char burnout is investigated in the limit of shrinking core combustion. As a first step, the particle temperature is assumed to proceed in the shrinking core regime and under conditions of negligible Stefan flow. The problem then reduces to calculating the oxygen concentration field around a non-spherical particle with the oxidation reaction taking place on the external surface. This problem has been addressed by an analytical technique and a numerical technique.… more
Date: January 17, 1990
Creator: Gavalas, G. R. & Flagan, R. C.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Particle correlations in JACEE (Japanese-American Cooperative Emulsion Experiment) nucleus-nucleus collisions

Description: Correlations in the production of charged particles and photons can be examined in detail in the central and forward rapidity range using high multiplicity ({ge}100 charged tracks) events from JACEE emulsion chambers. Results are presented on several forms of correlations studies. 9 refs., 2 figs.
Date: January 1, 1990
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Partner: UNT Libraries Government Documents Department
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Control of alpha particle transport by spatially inhomogeneous ion cyclotron resonance heating

Description: Control of the radial alpha particle transport by using Ion Cyclotron Range of Frequency waves is investigated in a large-aspect-ratio tokamak geometry. It is shown that spatially inhomogeneous ICRF-wave energy with properly selected frequencies and wave numbers can induce fast convective transport of alpha particles at the speed of order {upsilon}{sub alpha} {approximately} (P{sub RF}/n{sub {alpha}}{epsilon}{sub 0}) {rho}{sub p}, where P{sub RF} is the ICRF-wave power density, n{sub {alpha}} i… more
Date: February 1, 1990
Creator: Chang, C. S.; Imre, K.; Weitzner, H. (New York Univ., NY (USA). Courant Inst. of Mathematical Sciences) & Colestock, P. (Princeton Univ., NJ (USA). Plasma Physics Lab.)
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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A search for. nu. sub e appearance from stopped. pi. sup + and. mu. sup + decay at LAMPF (Los Alamos Meson Physics Facility)

Description: We report on a recent search for {bar {nu}}{sub e} appearance from stopped {pi}{sup +} {yields} {mu}{sup +}{nu}{sub {mu}} and {mu}{sup +} {yields} e{sup +}{nu}{sub e}{bar {nu}}{sub {mu}} decay made by the LAMPF experiment E645. The appearance of {bar {nu}}{sub e} may occur from {bar {nu}}{sub {mu}} {yields} {bar {nu}}{sub e}, {nu}{sub e} {yields} {bar {nu}}{sub eL}, or {nu}{sub {mu}} {yields} {bar {nu}}{sub eL} oscillations. Appearance may also occur from rare {mu}{sup +} {yields} e{sup +}{bar … more
Date: January 1, 1990
Creator: Fujikawa, B. K.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Electron positron factories

Description: In this paper, we will first indicate the key issues in designing a B-factory and a {phi}-factory, and illustrate the approaches that are being followed to address them. In general, reaching the B-factory parameter regime offers the most challenges, so we will emphasize it here. Then we will consider an extrapolation of our present understanding of collider performance and assess the maximum luminosity that could be anticipated. To reach extremely high luminosity, it may be necessary to conside… more
Date: December 1, 1990
Creator: Zisman, M. S.; Chattopadhyay, S.; Garren, A. A.; Lambertson, G. (Lawrence Berkeley Lab., CA (United States)); Bloom, E.; Corbett, W. J. et al.
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Partner: UNT Libraries Government Documents Department
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Multi-beam injector development at LBL

Description: LBL is developing a multi-beam injector that will be used for scaled accelerator experiments related to Heavy Ion Fusion. The device will produce sixteen 0.5 Amp beams of C+ at 2 MeV energy. The carbon arc source has been developed to the point where the emittance is within a factor of four of the design target. Modelling of the source behavior to find ways to reduce the emittance is discussed. Source lifetime and reliability is also of paramount importance to us and data regarding the lifetime… more
Date: June 1, 1990
Creator: Rutkowski, H. L.; Faltens, A.; Brodzik, D. A.; Johnson, R. M.; Pike, C. D.; Vanecek, D. L. (Lawrence Berkeley Lab., CA (United States)) et al.
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Partner: UNT Libraries Government Documents Department
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The search for low photodesorption coatings

Description: Low photo desorption (PSD) from surfaces of vacuum chambers increases the beam lifetime and reduces the cost of the pumping system of any storage ring. In compact rings where all radiated power ({approximately}10 kW) is incident on a few meters only, low PSD and good thermal conductivity of photon absorbers are of particular importance. An experimental chamber in which one meter long bars can be exposed to white photon beam with 500 eV critical energy has been built and installed on the U10B be… more
Date: January 1, 1990
Creator: Foerster, C.L. & Korn, G.
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Partner: UNT Libraries Government Documents Department
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Kinetic behavior of solid particles in fluidized beds

Description: The overall objectives of this project are to develop experimental techniques for measuring the forces of fluidized particles, and to predict the solid-gas performance in fluidized beds by using data analysis system, and by elucidating the intrinsic mechanism of erosion and attrition phenomena in fluidized beds. The reduction of erosion and attrition rates is one of the critical engineering problems for the design and operation of fluidized bed combustors. Specifically, the objectives are to: (… more
Date: June 1, 1990
Creator: Kono, H.O.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Selected problems in experimental intermediate energy physics

Description: The objectives of this research program are to: investigate forefront problems in experimental intermediate energy physics; educate students in this field of research; and, develop the instrumentation necessary to undertake this experimental program. Generally, the research is designed to search for physical processes which cannot be explained by conventional models of elementary interactions. This includes the use of nuclear targets where the nucleus provides a many body environment of strongl… more
Date: September 1, 1990
Creator: Mayes, B.W.; Hungerford, E.V. & Pinsky, L.S.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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An introduction to baryon violation in standard electroweak theory

Description: I shall begin with a qualitative overview of the anomaly and B violation at zero and non-zero temperature, demonstrating how these processes may be understood on the back of an envelope. Then I shall discuss a part of the formalism necessary for doing calculations in more detail. Specifically, B violation is related to various solutions to the Euclidean equations of motion; instantons, sphalerons, and calorons (also called periodic instantons). The applicability of the various solutions may be … more
Date: December 1, 1990
Creator: Arnold, P.B.
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Partner: UNT Libraries Government Documents Department
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J/. psi. and. Upsilon. production at CDF

Description: Characteristics of J/{psi} and {Upsilon} produced at the Tevatron and detected in the dimuon channel at CDF are reviewed. The masses of the J/{psi} and {Upsilon} are measured to be 3.096 {plus minus} 0.001 GeV/c{sup 2} and 9.469 {plus minus} 0.010 GeV/c{sup 2} respectively. These mass measurements are used to determine the systematic uncertainty on the momentum scale in the central tracking chamber. 2 refs., 14 figs.
Date: January 1, 1990
Creator: Liss, T. (Illinois Univ., Urbana, IL (USA))
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Partner: UNT Libraries Government Documents Department
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A new experimental limit on the electric dipole moment of the electron

Description: We describe a search for the electric dipole moment d{sub e} of the electron, carried out with {sup 205}Tl atoms in the ground state. The experiment makes use of the separated-oscillating-field magnetic-resonance method, laser state selection, fluorescence detection, and two counter-propagating atomic beams. Very careful attention is paid to systematic effects. The result for the atomic electric dipole moment is d{sub a} = (1.6 {plus minus} 5.0) {times} 10{sup {minus}24} e cm. If we assume the … more
Date: December 1, 1990
Creator: Carlberg, C.; Gould, H. (Lawrence Berkeley Lab., CA (USA)); Abdullah, K.; Commins, E.D. & Ross, S.B. (Lawrence Berkeley Lab., CA (USA) California Univ., Berkeley, CA (USA). Dept. of Physics)
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Partner: UNT Libraries Government Documents Department
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Genetic changes in Mammalian cells transformed by helium cells

Description: Midterm Syrian Hamster embryo (SHE) cells were employed to study high LET-radiation induced tumorigenesis. Normal SHE cells (secondary passage) were irradiated with accelerated helium ions at an incident energy of 22 MeV/u (9--10 keV/{mu}m). Transformed clones were isolated after growth in soft agar of cells obtained from the foci of the initial monolayer plated postirradiation. To study the progression process of malignant transformation, the transformed clones were followed by monolayer subcu… more
Date: November 1, 1990
Creator: Durante, M.; Grossi, G. (Naples Univ. (Italy). Dipt. di Scienze Fisiche); Yang, T.C. & Roots, R. (Lawrence Berkeley Lab., CA (USA))
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Partner: UNT Libraries Government Documents Department
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Non-evaporable getter investigation at the National Synchrotron Light Source

Description: We report H{sub 2}, CO and CO{sub 2} pumping speed measurements on a linear pump using NEG strip St 707 (Saes Getters Inc) as a function of both absorbed gases and number of activations. To simulate the conditions of an operating storage ring a gas mixture of 50% H{sub 2}, 35% CO and 15% CO{sub 2} is used in all measurements. Initial measured pumping speeds of >450{ell} m {sup {minus}1} s{sup {minus}1} decrease to 200 and 100{ell} m{sup {minus}1} s{sup {minus}1} for H{sub 2} and CO, respectivel… more
Date: January 1, 1990
Creator: Halama, H.J. & Guo, Y.
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Partner: UNT Libraries Government Documents Department
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The complexation behavior of neptunium and plutonium with nitrilotriacetic acid

Description: The first stability constant of NpO{sub 2}{sup +} with nitrilotriacetic acid (NTA) was determined at four ionic strengths (0.5, 1.0, 2.0, 3.0 M) using spectrophotometry. Nonlinear least-squares data fitting identified the complex as NpO{sub 2}NTA{sup 2-}. The Specific Ion Interaction Theory (S.I.T) approximation method was used to determine the stability constants at infinite dilution. First results on Pu{sup 4+} and PuO{sub 2}{sup 2+} complexation with NTA are reported. The stability constant … more
Date: August 1, 1990
Creator: Nitsche, H. & Becraft, K.
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Partner: UNT Libraries Government Documents Department
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Physics at the Planck scale

Description: Effective supergravity theories suggested by superstrings can be explored to determine their potential for successfully describing both observed physics at zero temperature and an inflationary cosmology. An important ingredient in this study is the dynamics of gaugino condensation, which has been the subject of recent activity. 33 refs., 2 figs.
Date: December 6, 1990
Creator: Gaillard, M.K. (Lawrence Berkeley Lab., CA (USA) California Univ., Berkeley, CA (USA). Dept. of Physics)
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Partner: UNT Libraries Government Documents Department
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Radiation-induced mesotheliomas in rats

Description: Mesotheliomas have been reported in rats that inhaled plutonium, but these tumors have not been extensively studied. To investigate a possible role for inhaled radionuclides in the induction of mesotheliomas, four life-span studies conducted at the Inhalation Toxicology Research Institute are reviewed. A total of 3076 F344 rats were exposed by inhalation to aerosols of {sup 239}PuO{sub 2}, mixed uranium-plutonium oxide, or {sup 144}CeO{sub 2}. Results showed that a low incidence of pleural meso… more
Date: January 1, 1990
Creator: Hahn, F. F.; Haley, P. J.; Hubbs, A. F.; Hoover, M. D. & Lundgren, D. L.
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Partner: UNT Libraries Government Documents Department
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Modeling of water spraying of field releases of hydrogen fluoride

Description: The effectiveness of water sprays to absorb HF releases has been recently demonstrated by extended laboratory and field tests. In this paper computer simulations are presented of the Hawk, Nevada Test Site, series of field tests, along with parametric studies of several cases which have not been studied in the field. The model used in these simulations, HFSPRAY, treats the gas-phase as an Eulerean fluid whereas the spray is described according to the Lagrangian approach by a finite number of dr… more
Date: October 14, 1990
Creator: Fthenakis, V.M. (Brookhaven National Lab., Upton, NY (United States)); Schatz, K.W. (Mobil Research and Development Corp., Princeton, NJ (United States)) & Zakkay, V. (New York Univ., NY (United States). Dept. of Applied Science)
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Partner: UNT Libraries Government Documents Department
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Combustion characterization of beneficiated coal-based fuels

Description: This three-year research project at Combustion Engineering, Inc. (CE), will assess the potential economic and environmental benefits derived from coal beneficiation by various advanced cleaning processes. The objectives of this program include the development of a detailed generic engineering data base, comprised of fuel combustion and ash performance data on beneficiated coal-based fuels (BCFs), which is needed to permit broad application. This technical data base will provide detailed informa… more
Date: March 1, 1990
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Nuclear and particle astrophysics

Description: We discuss the physics of matter that is relevant to the structure of compact stars. This includes nuclear, neutron star matter and quark matter and phase transitions between them. Many aspects of neutron star structure and its dependance on a number of physical assumptions about nuclear matter properties and hyperon couplings are investigated. We also discuss the prospects for obtaining constraints on the equation of state from astrophysical sources. Neuron star masses although few are known a… more
Date: October 31, 1990
Creator: Glendenning, N.K.
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Partner: UNT Libraries Government Documents Department
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