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PROSPECTS FOR PENTAQUARK SEARCHES IN E+D- ANNIHILATIONS AND VV COLLISIONS.

Description: Recent strong experimental evidence of a narrow exotic S = +1 baryon resonance, {Theta}{sup +}, suggests the existence of other exotic baryons. We discuss the prospects of confirming earlier experimental evidence of {Theta}{sup +} and the observation of additional hypothetical exotic baryons in e{sup +}e{sup -} annihilations and {gamma}{gamma} collisions at LEP and B Factories.
Date: June 28, 2004
Creator: ARMSTRONG,S.; MELLADO,B. & WU,S. L.
Partner: UNT Libraries Government Documents Department
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{phi} meson production in Au + Au and p + p collisions at {radical}s{sub NN}=200 GeV

Description: We report the STAR measurement of {psi} meson production in Au + Au and p + p collisions at {radical}s{sub NN} = 200 GeV. Using the event mixing technique, the {psi} spectra and yields are obtained at midrapidity for five centrality bins in Au+Au collisions and for non-singly-diffractive p+p collisions. It is found that the {psi} transverse momentum distributions from Au+Au collisions are better fitted with a single-exponential while the p+p spectrum is better described by a double-exponential … more
Date: June 1, 2004
Creator: Adams, J.; Adler, C.; Aggarwal, M. M.; Ahammed, Z.; Amonett, J.; Anderson, B. D. et al.
Partner: UNT Libraries Government Documents Department
open access

Observation of Self-Sputtering in Energetic Condensation of Metal Ions

Description: The condensation of energetic metal ions on a surface may cause self-sputtering even in the absence of substrate bias. Charge-state-averaged self-sputtering yields were determined for both zirconium and gold ions generated by a cathodic vacuum arc. Films were deposited on differently biased substrates exposed to streaming Zr and Au vacuum arc plasma. The self-sputtering yields for both metals were estimated to be about 0.05 in the absence of bias, and exceeding 0.5 when bias reached-50 V. These… more
Date: June 16, 2004
Creator: Anders, Andre
Partner: UNT Libraries Government Documents Department
open access

An Investigation of Solid-State Amidization and Imidization Reactions in Vapor Deposited Poly (amic acid)

Description: The condensation polymerization reaction of 4,4'-oxydianiline (ODA) with pyromellitic dianhydride (PMDA) to form poly(amic acid) and the subsequent imidization reaction to form polyimide were investigated for films prepared using vapor deposition polymerization techniques. Fourier-transform infrared spectroscopy (FT-IR), thermal analysis, and matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) of films at different temperatures indicate that additional so… more
Date: June 28, 2004
Creator: Anthamatten, M; Letts, S A; Day, K; Cook, R C; Gies, A P; Hamilton, T P et al.
Partner: UNT Libraries Government Documents Department
open access

Azimuthally sensitive hanbury brown-twiss interferometry in Au + Au collisions sqrt S sub NN = 200 GeV

Description: We present the results of a systematic study of the shape of the pion distribution in coordinate space at freeze-out in Au+Au collisions at RHIC using two-pion Hanbury Brown-Twiss (HBT) interferometry. Oscillations of the extracted HBT radii vs. emission angle indicate sources elongated perpendicular to the reaction plane. The results indicate that the pressure and expansion time of the collision system are not sufficient to completely quench its initial shape.
Date: June 6, 2004
Creator: Argonne National Laboratory
Partner: UNT Libraries Government Documents Department
open access

Nonabelian Monopoles

Description: We study topological as well as dynamical properties of BPS nonabelian magnetic monopoles of Goddard-Nuyts-Olive-Weinberg type in $ G=SU(N)$, $USp(2N)$ and SO(N) gauge theories, spontaneously broken to nonabelian subgroups $H$. We find that monopoles transform under the group dual to $H$ in a tensor representation of rank determined by the corresponding element in $\pi_1(H)$. When the system is embedded in a $\cal N=2$ supersymmetric theory with an appropriate set of flavors with appropriate ba… more
Date: June 23, 2004
Creator: Auzzi, Roberto; Bolognesi, Stefano; Evslin, Jarah; Konishi, Kenichi & Murayama, Hitoshi
Partner: UNT Libraries Government Documents Department
open access

Bioremediation of Petroleum and Radiological Contaminated Soils at the Savannah River Site: Laboratory to Field Scale Applications

Description: In the process of Savannah River Site (SRS) operations limited amounts of waste are generated containing petroleum, and radiological contaminated soils. Currently, this combination of radiological and petroleum contaminated waste does not have an immediate disposal route and is being stored in low activity vaults. SRS developed and implemented a successful plan for clean up of the petroleum portion of the soils in situ using simple, inexpensive, bioreactor technology. Treatment in a bioreactor … more
Date: June 7, 2004
Creator: BRIGMON, ROBINL.
Partner: UNT Libraries Government Documents Department
open access

Involvement of Linear Plasmids in Aerobic Biodegradation of Vinyl Chloride

Description: Pseudomonas putida strain AJ and Ochrobactrum strain TD were isolated from hazardous waste sites based on their ability to use vinyl chloride (VC) as a sole source of carbon and energy under aerobic conditions. Strains AJ and TD also use ethene and ethylene oxide as growth substrates. Strain AJ contained a linear megaplasmid (approximately 260 kb) when grown on VC or ethene, but no circular plasmids. While growing on ethylene oxide, the size of the linear plasmid in strain AJ decreased to appro… more
Date: June 14, 2004
Creator: BRIGMON, ROBINL.
Partner: UNT Libraries Government Documents Department
open access

Type IIP supernovae as cosmological probes: A SEAM distance to SN1999em

Description: Because of their intrinsic brightness, supernovae make excellent cosmological probes. We describe the spectral-fitting expanding atmosphere method (SEAM) for obtaining distances to Type IIP supernovae (SNe IIP) and present a distance to SN 1999em for which a Cepheid distance exists. Our models give results consistent with the Cepheid distance, even though we have not attempted to tune the underlying hydrodynamical model but have simply chosen the best fits. This is in contradistinction to the e… more
Date: June 1, 2004
Creator: Baron, E.; Nugent, Peter E.; Branch, David & Hauschildt, Peter H.
Partner: UNT Libraries Government Documents Department
open access

Design Issues for the Superconducting Magnet that Goes Around theLiquid Hydrogen Absorber for the Muon Ionization Cooling Experiment(MICE)

Description: This report describes the design issues that are associated with a superconducting focusing solenoid that goes around a liquid hydrogen absorber for the Muon Ionization Cooling Experiment (MICE) proposed for the Rutherford Appleton Laboratory. The solenoid consists of two superconducting coils that may operated at the same polarity or at opposite polarities. As a result, the coils and their support structure must be designed to carry a 360-ton inter-coil force that is forcing the coils apart al… more
Date: June 15, 2004
Creator: Barr, G.; Cobb, J. H.; Green, M. A.; Lau, W.; R. S., Senanayake; Yang, S. Q. et al.
Partner: UNT Libraries Government Documents Department
open access

An Overview of High Energy Short Pulse Technology for Advanced Radiography of Laser Fusion Experiments

Description: The technical challenges and motivations for high-energy, short-pulse generation with NIF-class, Nd:glass laser systems are reviewed. High energy short pulse generation (multi-kilojoule, picosecond pulses) will be possible via the adaptation of chirped pulse amplification laser techniques on the NIF. Development of meter-scale, high efficiency, high-damage-threshold final optics is a key technical challenge. In addition, deployment of HEPW pulses on NIF is constrained by existing laser infrastr… more
Date: June 18, 2004
Creator: Barty, C. J.; Key, M.; Britten, J.; Beach, R.; Beer, G.; Brown, C. et al.
Partner: UNT Libraries Government Documents Department
open access

Synthesis of High Surface Area Alumina Aerogels without the Use of Alkoxide Precursors

Description: Alumina aerogels were prepared through the addition of propylene oxide to aqueous or ethanolic solutions of hydrated aluminum salts, AlCl{sub 3} {center_dot} 6H{sub 2}O or Al(NO{sub 3}){sub 3} {center_dot} 9H{sub 2}O, followed by drying with supercritical CO{sub 2}. This technique affords low-density (60-130 kg/m{sup 3}), high surface area (600-700 m{sup 2}/g) alumina aerogel monoliths without the use of alkoxide precursors. The dried alumina aerogels were characterized using elemental analysis… more
Date: June 25, 2004
Creator: Baumann, T. F.; Gash, A. E.; Chinn, S. C.; Sawvel, A. M.; Maxwell, R. S. & Satcher, J. H.
Partner: UNT Libraries Government Documents Department
open access

Virtual Building Environments (VBE) - Applying Information Modeling to Buildings

Description: A Virtual Building Environment (VBE) is a ''place'' where building industry project staffs can get help in creating Building Information Models (BIM) and in the use of virtual buildings. It consists of a group of industry software that is operated by industry experts who are also experts in the use of that software. The purpose of a VBE is to facilitate expert use of appropriate software applications in conjunction with each other to efficiently support multidisciplinary work. This paper define… more
Date: June 21, 2004
Creator: Bazjanac, Vladimir
Partner: UNT Libraries Government Documents Department
open access

Incipient Spallation Fracture in Light Metals From 3D X-Ray Tomography, 2D Microscopy, and Molecular Dynamics Simulations

Description: The dynamic fracture of ductile metals is known to occur through the nucleation and growth of microscopic voids. As the voids grow, the surrounding metal is plastically deformed to accommodate the change in void volume. In order to gain better insight into void growth, gas gun recovery experiments were used to study incipient spallation fracture in light metals (Al, Cu, V). In addition to in-situ free surface velocity wave-profiles, the recovered samples were first analyzed using 3D X-ray tomog… more
Date: June 24, 2004
Creator: Belak, J; Cazamias, J U; Chau, R; Haupt, D; Kinney, J H; Kumar, M et al.
Partner: UNT Libraries Government Documents Department
open access

Anaerobic, Nitrate-Dependent Oxidation of U(IV) Oxide Minerals by the Chemolithoautotrophic Bacterium Thiobacillus denitrificans

Description: Under anaerobic conditions and at circumneutral pH, cells of the widely-distributed, obligate chemolithoautotrophic bacterium Thiobacillus denitrificans oxidatively dissolved synthetic and biogenic U(IV) oxides (uraninite) in nitrate-dependent fashion: U(IV) oxidation required the presence of nitrate and was strongly correlated to nitrate consumption. This is the first report of anaerobic U(IV) oxidation by an autotrophic bacterium.
Date: June 25, 2004
Creator: Beller, H R
Partner: UNT Libraries Government Documents Department
open access

Computational Needs for Muon Accelerators.

Description: Muon accelerators contain beam lines and components which are unlike any found in existing accelerators. Production of the muons requires targets for beams with powers which are at or beyond what has currently been achieved. Many subsystems use solenoid focusing systems where at any given point, several magnets have a significant influence. The beams that are transported can have energy spreads of {+-}30% or more. The required emittances necessitate accurate tracking of particles with angles of… more
Date: June 29, 2004
Creator: Berg, J. S.
Partner: UNT Libraries Government Documents Department
open access

Barrier rf systems in synchrotrons

Description: Recently, many interesting applications of the barrier RF system in hadron synchrotrons have been realized. A remarkable example of this is the development of longitudinal momentum mining and implementation at the Fermilab Recycler for extraction of low emittance pbars for the Tevatron shots. At Fermilab, we have barrier RF systems in four different rings. In the case of Recycler Ring, all of the rf manipulations are carried out using a barrier RF system. Here, the author reviews various uses o… more
Date: June 28, 2004
Creator: Bhat, Chandra M.
Partner: UNT Libraries Government Documents Department
open access

Diagnostics for intense heavy ion beams in the HIF-VNL

Description: Modern diagnostic techniques provide detailed information on beam conditions in injector, transport, and final focus experiments in the HIF-VNL. Parameters of interest include beam current, beam energy, transverse and longitudinal distributions, emittance, and space charge neutralization. Imaging techniques, based on kapton films and optical scintillators, complement and in some cases, may replace conventional techniques based on slit scans. Time-resolved optical diagnostics that provide 4-D tr… more
Date: June 11, 2004
Creator: Bieniosek, F. M.; Eylon, S.; Faltens, A.; Friedman, A.; Kwan, J. W.; Leitner, M. A. et al.
Partner: UNT Libraries Government Documents Department
open access

Late effects from hadron therapy

Description: Successful cancer patient survival and local tumor control from hadron radiotherapy warrant a discussion of potential secondary late effects from the radiation. The study of late-appearing clinical effects from particle beams of protons, carbon, or heavier ions is a relatively new field with few data. However, new clinical information is available from pioneer hadron radiotherapy programs in the USA, Japan, Germany and Switzerland. This paper will review available data on late tissue effects fr… more
Date: June 1, 2004
Creator: Blakely, Eleanor A. & Chang, Polly Y.
Partner: UNT Libraries Government Documents Department
open access

Top physics: CDF results

Description: The top quark plays an important role in the grand scheme of particle physics, and is also interesting on its own merits. We present recent results from CDF on top-quark physics based on 100-200 pb{sup -1} of p{bar p} collision data. We have measured the t{bar t} cross section in different decay modes using several different techniques, and are beginning our studies of top-quark properties. New analyses for this conference include a measurement of {sigma}{sub t{bar t}} in the lepton-plus-jets c… more
Date: June 23, 2004
Creator: Bloom, K.
Partner: UNT Libraries Government Documents Department
open access

Spatially Continuous Mixed P2-P1 Solutions for Planar Geometry

Description: Even-order Legendre polynomial (P{sub N}) expansion approximations of the neutron transport equation have historically seen only limited practical application. Research in the last decade has resolved one of the historical theoretical objections to the use of even-order PN approximations in planar geometry, namely the ambiguity in the prescription of boundary conditions as a result of an odd number of unknowns. This research also demonstrated the P{sub 2} approximation to be more accurate than … more
Date: June 4, 2004
Creator: Brantley, P S
Partner: UNT Libraries Government Documents Department
open access

Investigation of Microwave Transitions and Nonlinear Magneto-Optical Rotation in Anti-Relaxation-Coated Cells

Description: Using laser optical pumping, widths and frequency shifts are determined for microwave transitions between the components of the ground-state hyperfine structure for {sup 85}Rb and {sup 87}Rb atoms contained in vapor cells with alkane anti-relaxation coatings. The results are compared with data on Zeeman relaxation obtained in nonlinear magneto-optical rotation (NMOR) experiments, a comparison important for quantitative understanding of spin-relaxation mechanisms in coated cells. By comparing ce… more
Date: June 4, 2004
Creator: Budker, D.; Hollberg, L.; Kimball, D. F.; Kitching, J.; Pustelny, S.; Robinson, H. G. et al.
Partner: UNT Libraries Government Documents Department
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