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Composite weak bosons

Description: Dynamical mechanism of composite W and Z is studied in a 1/N field theory model with four-fermion interactions in which global weak SU(2) symmetry is broken explicitly by electromagnetic interaction. Issues involved in such a model are discussed in detail. Deviation from gauge coupling due to compositeness and higher order loop corrections are examined to show that this class of models are consistent not only theoretically but also experimentally.
Date: April 1, 1988
Creator: Suzuki, M.
Partner: UNT Libraries Government Documents Department

Composite weak bosons at supercolliders

Description: Following a brief survey of nongauge interactions of composite W and Z from a theoretical viewpoint, we point out some of conspicuous signatures of compositeness at supercolliders, in particular W..gamma.. and Z..gamma.. production through q anti q by interactions of dimension six. In these processes, a suppression factor 1/..lambda../sup 2/ due to compositeness scale ..lambda.. is largely compensated by longitudinal polarizations of W and Z, allowing us to probe up to high values of ..lambda... 10 refs., 3 figs.
Date: June 1, 1987
Creator: Suzuki, Mahiko
Partner: UNT Libraries Government Documents Department

New limit on the oscillation between nu/sub. mu. / and nu/sub e/

Description: Measurements have been made of the reactions nu/sub e/n ..-->.. e/sup -/p and nu/sub ..mu../n ..-->.. ..mu../sup -/p by wide band neutrino beam in a detector located an effective distance of 96m from a neutrino source. No evidence for the oscillation nu/sub ..mu../ ..-->.. nu/sub e/ is found.
Date: January 1, 1984
Creator: Suzuki, Y.
Partner: UNT Libraries Government Documents Department

Heavy quark jets

Description: The present understanding of heavy quark fragmentation is reviewed, and the expected behaviors of heavy quark jets is discussed. Included are short-distance versus long-distance parts of fragmentation, fragmentation dynamics at long distances, universal hadronization in rapidity plot, the heavy quark as a sizzling fireball, quantum chromodynamics ladder summation in the region of K/sub T/ < ..lambda.., and the relevance or irrelevance to super high energy experiment. 6 references. (JFP)
Date: November 12, 1979
Creator: Suzuki, M.
Partner: UNT Libraries Government Documents Department

Inelastic final-state interaction

Description: The final-state interaction in multichannel decay processes is systematically studied with application to B decay in mind. Since the final-state interaction is intrinsically interwoven with the decay interaction in this case, no simple phase theorem like&quot;Watson&#39;s theorem&quot; holds for experimentally observed final states. We first examine in detail the two-channel problem as a toy-model to clarify the issues and to remedy common mistakes made in earlier literature. Realistic multichannel problems are too challenging for quantitative analysis. To cope with mathematical complexity, we introduce a method of approximation that is applicable to the case where one prominent inelastic channel dominates over all others. We illustrate this approximation method in the amplitude of the decay B to pi K fed by the intermediate states of a charmed meson pair. Even with our approximation we need more accurate information of strong interactions than we have now. Nonetheless we are able to obtain some insight in the issue and draw useful conclusions on general features on the strong phases.
Date: October 29, 2007
Creator: Suzuki, Mahiko & Suzuki, Mahiko
Partner: UNT Libraries Government Documents Department

Production of charmed meson pairs in electron--positron annihilation

Description: Production of charmed meson pairs of J/sup P/ = 0/sup -/ and 1/sup -/ is examined near the threshold. Production cross sections are parametrized by a quark model of a broken SU(8) symmetry. The charmed hadron production is dominated by (0/sup -/,1/sup -/) pairs, and D* anti D* production comes out to be much too small to reproduce the higher peak in the recoil mass spectrum against D/sup 0/ (anti D/sup 0/) through reflection. A few experimental measurements are pointed out that will clarify the origin of the higher peak of the recoil mass spectrum.
Date: August 27, 1976
Creator: Suzuki, M. & Wada, W. W.
Partner: UNT Libraries Government Documents Department

Study of reduced order model reference adaptive control systems for improved process control. Final report, May 1, 1982-January 31, 1986

Description: The objective of this research is to provide a method for design of control systems when the plant involved is highly variable in both structure and parameter values. This typifies many manufacturing processes, which in general are highly sensitive to intrinsic properties of the infeed material, have poorly understood or controlled boundary conditions, and often have highly non-linear characteristics. In addition, the disturbances most frequent in a manufacturing process are best characterized as parameter changes rather than state variable changes. The choice of a parameter adaptive control paradigm is obvious since it has the property of optimizing system response characteristics in the face of wide plant parameter variations. Model Reference Adaptive Systems (MRAS) enjoy an ease of performance specification, and again seem applicable; however, there is a restriction within current theory that the plant be characterized in its structure well enough to have a reference model of identical order. This restriction implies a static plant structure and more a priori information than is often present. During this contract the basic design characteristics of certain MRAS have been studied and problems with reduced order models identified, such as noise and input magnitude sensitivity and instability caused by high frequency learning signals. This has lead to certain solutions and resulting guidelines for design. This is then followed by design studies for a position servomechanism (which serves as the foundation of many automated manufacturing processes). This study expanded the domain from MRAS to self-tuning controllers (STC) and found that both can deal with reduced order models if the initial parameter values are not too distant from the actual values. However, the STC appears to be the more robust. 12 refs., 56 figs.
Date: February 1, 1986
Creator: Hardt, D.E.; Papadpoulos, E. & Suzuki, A.
Partner: UNT Libraries Government Documents Department

Nonlinear response of graphite structures

Description: A nonlinear constitutive relation for graphite under three-dimensional stress states is presented for the finite element stress analysis. In the constitutive formulation, graphite is assumed to be transversely isotropic and an incremental stress-strain law is utilized in conjunction with a loading function which is used to specify the elastic or elastic-plastic state of deformations. The loading function is also used to define the strain-hardening of the material starting from the initial yielding state to the failure (or fracture) state. Therefore, by using this constitutive relation, not only the nonlinear load-deformation response of graphite is determined, but also its failure load and corresponding failure mode can be predicted.
Date: January 1, 1977
Creator: Chang, T. Y.; Reich, M. & Suzuki, H.
Partner: UNT Libraries Government Documents Department

Long-term research in Japan: amorphous metals, metal oxide varistors, high-power semiconductors and superconducting generators

Description: The review revealed that significant activity is under way in the research of amorphous metals, but that little fundamental work is being pursued on metal oxide varistors and high-power semiconductors. Also, the investigation of long-term research program plans for superconducting generators reveals that activity is at a low level, pending the recommendations of a study currently being conducted through Japan's Central Electric Power Council.
Date: April 1, 1985
Creator: Hane, G.J.; Yorozu, M.; Sogabe, T. & Suzuki, S.
Partner: UNT Libraries Government Documents Department

Approximate gauge symemtry of composite vector bosons

Description: It can be shown in a solvable field theory model that the couplings of the composite vector mesons made of a fermion pair approach the gauge couplings in the limit of strong binding. Although this phenomenon may appear accidental and special to the vector bosons made of a fermion pair, we extend it to the case of bosons being constituents and find that the same phenomenon occurs in more an intriguing way. The functional formalism not only facilitates computation but also provides us with a better insight into the generating mechanism of approximate gauge symmetry, in particular, how the strong binding and global current conservation conspire to generate such an approximate symmetry. Remarks are made on its possible relevance or irrelevance to electroweak and higher symmetries.
Date: June 1, 2010
Creator: Suzuki, Mahiko
Partner: UNT Libraries Government Documents Department

Redox behavior below 1000K of Pt-impregnated CeO{sub 2}-ZrO{sub 2} solid solutions : an in-situ neutron diffraction study.

Description: The Ce{sup 3+} {leftrightarrow} Ce{sup 4+} redox process in automotive three-way catalysts such as Ce-ZrO{sub 2}/Pt provides an essential mechanism to oxygen storage/release under dynamic air-to-fuel ratio cycling. Such a function requires a metal-support interaction which is not completely understood. We have carried out an in-situ neutron powder diffraction study to monitor the crystal structures (a mixture of a major tetragonal and a minor monoclinic phase) of 10mol% Ce-doped ZrO{sub 2} with and without Pt (1wt%) impregnation under oxidizing and reducing conditions over the temperature range of 25--7000 C. The samples were heated first in flowing 2%O{sub 2}/Ar from room temperature to 400 C and then in 1%CO/Ar to about 700 C. A discontinued increase of the tetragonal unit-cell volume, a decrease of tetragonality (c/a), and a change of color from light yellow to gray when changing from oxidizing to reducing atmosphere were observed only in the sample containing Pt. This result supports the model which assumes the formation of oxygen vacancies initially near the Pt atoms. As more Ce ions are reduced from 4+ to 3+ oxidation states at high temperatures, oxygen vacancies migrate to the bulk of the oxide particles.
Date: January 12, 1998
Creator: Loong, C.-K.; Short, S. M.; Ozawa, M. & Suzuki, S.
Partner: UNT Libraries Government Documents Department

Dynamic response of physisorbed hydrogen molecules on lanthanide-modified zirconia nanoparticles

Description: Ultrafine lanthanide (Ln = Ce and Nd)-modified zirconia powders synthesized by a coprecipitation method exhibit high surface areas and adsorption sites that are essential for catalytic applications. We report a study of the surface chemistry of Ce{sub 0.1}Zr{sub 0.9}O{sub 2} and Nd{sub 0.1}Zr{sub 0.9}O{sub 1.95} powders. First, the specific surface area and porosity are characterized by nitrogen isotherm-adsorption measurements. Second, the motion of hydrogen molecules physisorbed on Ce- and Nd-doped zirconias is studied by inelastic neutron scattering. Nitrogen adsorption-desorption isotherm measurements yield a BET surface area (26.1 m{sup 2}/g) and mesopore size ({approximately}5 nm radius) in Ce{sub 0.1}Zr{sub 0.9}O{sub 2} as compared to those (72.3 m{sup 2}/g and {approximately}3 nm) in Nd{sub 0.1}Zr{sub 0.9} O{sub 1.95}. The vibrational densities of states of H{sub 2} on Ce{sub 0.1}Zr{sub 0.9}O{sub 2} and Nd{sub 0.1}Zr{sub 0.9}O{sub 1.95} were measured at 20 K over the 0-200 meV energy range for three hydrogen coverage. The spectra for both samples consist of two parts: a sharp peak at {approximately}14.5 meV and a broad component extending beyond 200 meV. The sharp peak corresponds to transitions from the J=0 to J=1 rotational states of bulk hydrogen molecules, and its intensity decreases with decreasing H{sub 2} coverage. The broad component corresponds to overdamped motion of surface adsorbed hydrogen molecules. The major difference in the latter component between the Ce- and Nd-doped samples is an excess of intensities in the 5-14 meV region in Nd{sub 0.1}Zr{sub 0.9}O{sub 1.95}. The confined motion of adsorbed H{sub 2} on the different micropore and mesopore surfaces of Ce{sub 0.1}Zr{sub 0.9}O{sub 2} and Nd{sub 0.1}Zr{sub 0.9}O{sub 1.95} is discussed.
Date: October 1, 1997
Creator: Loong, C.K.; Trouw, F.; Ozawa, Masakuni & Suzuki, Suguru
Partner: UNT Libraries Government Documents Department

A laser spectroscopic study of Nd-doped Zirconia

Description: High-surface-area rare-earth (RE) modified zirconia powders prepared by solution methods can be used as catalytic support of noble metals and as electrolyte oxygen sensors in automobile exhaust-emission- control systems. Previous neutron-scattering study showed that substituting Zr with trivalent RE ions not only stabilizes the cubic and tetrgonal phases over a wide range of temperatures but also creates oxygen vacancies in the RE-Zr oxide solid solution. This work focuses on Nd fluorescence in Nd{sub 0.1}Zr{sub 0.9}O{sub 1.95} powders under laser excitation of the Nd{sup 3+} ground state to the {sup 4}G{sub 7.2} states. Distinct features were found at 8K in the {sup 4}I{sub 9/2}{r_arrow}{sup 4}G{sub 7/2} excitation and {sup 4}F{sub 3.2}{r_arrow}{sup 4}I{sub 9/2} emission spectra using two sets of incident and emission frequencies, respectively. Results are discussed in terms of site-sensitive local structures surrounding the Nd ions in the two-phased oxide structure.
Date: June 1, 1996
Creator: Loong, C.-K.; Liu, G.K.; Ozawa, M. & Suzuki, S.
Partner: UNT Libraries Government Documents Department

Crystal phases and lattice dynamics of slip-cast {beta}{prime}-sialons

Description: The crystal structures and phonon densities of states (DOS) of {beta}{prime}-Sialon ceramics, Si{sub 6-z}Al{sub z}O{sub z}N{sub 8-z} (O {le} z {le} 6), prepared by a novel slip-cast method were studied by neutron scattering techniques. A Rietveld analysis of the diffraction patterns shows that samples of z < 4 form a single-phase solid solution of Si-Al-O-N isostructural to {beta}-Si{sub 3}N{sub 4} (space group P6{sub 3}/m). Within this structure there is a consistent preferred occupation of O on the 2c sites and N on the 6h sites. For z > 4 the materials exhibit multiple-phase structure. The observed phonon DOS of the O {le} z {le} 4 ceramics displays phonon bands at about 50 and 115 meV. These features are considerably broader than the corresponding ones in {beta}-Si{sub 3}N{sub 4} powder. As z increases, effects due to atomic disorder lead to an overlap of the two phonon bands and a complete fill up of the phonon gap at {approximately} 100 meV observed in Si{sub 3}N{sub 4}.
Date: December 31, 1995
Creator: Loong, C.K.; Richardson, J.W. Jr.; Suzuki, S. & Ozawa, M.
Partner: UNT Libraries Government Documents Department

Elusive Vector Glueball

Description: If the vector glueball {Omicron} exists in the mass range that theory suggests, its resonant production cross section can be detected in e{sup +}e{sup -} annihilation only if the decay width is very narrow ({le} a few MeV). Otherwise {Omicron} will be observed only indirectly through its mixing with {psi}{prime}. We propose a few tests of the {Omicron}-{psi}{prime} mixing for future charm factories.
Date: May 1, 2002
Creator: Suzuki, Mahiko
Partner: UNT Libraries Government Documents Department

Iron Phosphate Glass as Potential Waste Matrix for High-Level Radioactive Waste

Description: Recently, Iron Phosphate Glass (IPG) is investigated as the alternative final waste form for High-Level Radioactive Waste (HLW) in U.S. This study is aimed to investigate feasibility of IPG to HLW arising from commercial reprocessing in Japan. In order to evaluate favorable preparation conditions, maximum waste loading and property of IPG, the melting tests were carried. From the results of melting tests, the favorable preparation conditions was with matrix of Fe/P 0.43 (mole ratio in products) and melting at 1200{sup o} for 4h. The products of 10-20mass% waste loading of simulated HLW were glassy and had no crystal peaks, however the product of 30mass% waste loading showed some crystal peaks by XRD analysis. IPG and Borosilicate glass (BG) had about the same thermal properties. As a result, IPG had enough potential for high waste loading and the extremely good chemical durability for consideration as a waste form for Japanese HLW.
Date: February 25, 2003
Creator: Fukui, T.; Ishinomori, T.; Endo, Y.; Sazarashi, M.; Ono, S. & Suzuki, K.
Partner: UNT Libraries Government Documents Department


Description: The Nuclear Power Engineering Corporation (NUPEC) of Japan has been conducting a multi-year research program to investigate the behavior of nuclear power plant piping systems under large seismic loads. The objectives of the program are: to develop a better understanding of the elasto-plastic response and ultimate strength of nuclear piping; to ascertain the seismic safety margin of current piping design codes; and to assess new piping code allowable stress rules. Under this program, NUPEC has performed a large-scale seismic proving test of a representative nuclear power plant piping system. In support of the proving test, a series of materials tests, static and dynamic piping component tests, and seismic tests of simplified piping systems have also been performed. As part of collaborative efforts between the United States and Japan on seismic issues, the US Nuclear Regulatory Commission (USNRC) and its contractor, the Brookhaven National Laboratory (BNL), are participating in this research program by performing pre-test and post-test analyses, and by evaluating the significance of the program results with regard to safety margins. This paper describes BNL's pre-test analysis to predict the elasto-plastic response for one of NUPEC's simplified piping system seismic tests. The capability to simulate the anticipated ratcheting response of the system was of particular interest. Analyses were performed using classical bilinear and multilinear kinematic hardening models as well as a nonlinear kinematic hardening model. Comparisons of analysis results for each plasticity model against test results for a static cycling elbow component test and for a simplified piping system seismic test are presented in the paper.
Date: August 17, 2003
Partner: UNT Libraries Government Documents Department