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Purgatorio - A new implementation of the Inferno algorithm

Description: For astrophysical applications, as well as modeling laser-produced plasmas, there is a continual need for equation-of-state data over a wide domain of physical conditions. This paper presents algorithmic aspects for computing the Helmholtz free energy of plasma electrons for temperatures spanning from a few Kelvin to several KeV, and densities ranging from essentially isolated ion conditions to such large compressions that most bound orbitals become delocalized. The objective is high precision … more
Date: March 29, 2005
Creator: Wilson, B; Sonnad, V; Sterne, P & Isaacs, W
Partner: UNT Libraries Government Documents Department
open access

Stragegies to Detect Hidden Geothermal Systems Based on Monitoringand Analysis of CO2 in the Near-Surface Environment

Description: We investigate the potential for CO2 monitoring in thenear-surface environment as an approach to exploration for hiddengeothermal systems. Numerical simulations of CO2 migration from a modelhidden geothermal system show that CO2 concentrations can reach highlevels in the shallow subsurface even for relatively low CO2 fluxes.Therefore, subsurface measurements offer an advantage over above-groundmeasurements which are affected by winds that rapidly disperse CO2. Tomeet the challenge of detecting … more
Date: March 29, 2005
Creator: Lewicki, Jennifer L. & Oldenburg, Curtis M.
Partner: UNT Libraries Government Documents Department
open access

Using measured equipment load profiles to 'right-size' HVACsystems and reduce energy use in laboratory buildings (Pt. 2)

Description: There is a general paucity of measured equipment load datafor laboratories and other complex buildings and designers often useestimates based on nameplate rated data or design assumptions from priorprojects. Consequently, peak equipment loads are frequentlyoverestimated, and load variation across laboratory spaces within abuilding is typically underestimated. This results in two design flaws.Firstly, the overestimation of peak equipment loads results in over-sizedHVAC systems, increasing initia… more
Date: June 29, 2005
Creator: Mathew, Paul; Greenberg, Steve; Frenze, David; Morehead, Michael; Sartor, Dale & Starr, William
Partner: UNT Libraries Government Documents Department
open access

Shape transitions in neutron-rich Ru isotopes: spectroscopy of 109,110,111,112Ru

Description: The spectroscopy of neutron-rich {sup 109,110,111,112}Ru nuclei was studied by measuring the prompt {gamma} rays originated from fission fragments, produced by the {sup 238}U({alpha},f) fusion-fission reaction, in coincidence with the detection of both fragments. For {sup 109,111}Ru, both the negative-parity (h{sub 11/2} orbitals) and positive-parity (g{sub 7/2} and/or d{sub 5/2} orbitals) bands were extended to substantially higher spin and excitation energy than known previously. The ground-s… more
Date: June 29, 2005
Creator: Hua, H.; Cline, D.; Hayes, A. B.; Teng, R.; Riley, D.; Clark, R. M. et al.
Partner: UNT Libraries Government Documents Department
open access

Establishing Ergonomics in Industrially Developing Countries

Description: The introduction of ergonomics is an ongoing effort in industrially developing countries and will ultimately require an organized, programmatic approach spanning several countries and organizations. Our preliminary efforts with our partner countries of Viet Nam, Thailand, and Nicaragua have demonstrated that a one-time course is just the first step in a series of necessary events to provide skills and create an infrastructure that will have lasting impact for the host country. To facilitate tha… more
Date: August 29, 2005
Creator: Stewart, K.; Silverstein, B. & Kiefer, M.
Partner: UNT Libraries Government Documents Department
open access

Dynamic Response of Copper Subjected to Quasi-Isentropic, Gas-Gun Driven Loading

Description: A transmission electron microscopy study of quasi-isentropic high-pressure loading (peak pressures between 18 GPa and 52 GPa) of polycrystalline and monocrystalline copper was carried out. Deformation mechanisms and defect substructures at different pressures were analyzed. Current evidence suggests a deformation substructure consisting of twinning at the higher pressures and heavily dislocated laths and dislocation cells at the intermediate and lower pressures, respectively. Evidence of stacki… more
Date: September 29, 2005
Creator: Jarmakani, H.; McNaney, J. M.; Schneider, M. S.; Orlikowski, D.; Nguyen, J. H.; Kad, B. et al.
Partner: UNT Libraries Government Documents Department
open access

Calibration of symmetric and non-symmetric errors for interferometry of ultra-precise imaging systems

Description: The azimuthal Zernike coefficients for shells of Zernike functions with shell numbers n<N may be determined by making measurements at N equally spaced rotational positions. However, these measurements do not determine the coefficients of any of the purely radial Zernike functions. Label the circle that the azimuthal Zernikes are measured in as circle A. Suppose that the azimuthal Zernike coefficients for n<N are also measured in a smaller circle B which is inside circle A but offset so th… more
Date: June 29, 2005
Creator: Phillion, D. W.; Sommargren, G. E.; Johnson, M. A.; Decker, T. A.; Taylor, J. S.; Gomie, Y et al.
Partner: UNT Libraries Government Documents Department
open access

Branching Fraction for B0 -> pi- l+ nu and Determination of |Vub| in Upsilon(4S) -> B0 B0bar Events Tagged by B0bar -> D(*)+ l- nubar

Description: We report preliminary results from a study of the charmless exclusive semileptonic decay B{sup 0} {yields} {pi}{sup -}{ell}{sup +}{nu} based on the data collected at the {Upsilon}(4S) resonance using the BABAR detector at SLAC. The analysis uses events in which the signal B meson recoils against a B meson that has been reconstructed in a semileptonic decay {bar B}{sup 0} {yields} D{sup (*)+}{ell}{sup -}{bar {nu}}. We extract the total branching fraction {Beta}(B{sup 0} {yields} {pi}{sup -}{ell}… more
Date: June 29, 2005
Creator: Aubert, B.; Barate, R.; Boutigny, D.; Couderc, F.; Karyotakis, Y.; Lees, J. P. et al.
Partner: UNT Libraries Government Documents Department
open access

Deducing the 237U(n,f) cross-section using the Surrogate Ratio Method

Description: The authors have deduced the cross section for {sup 237}U(n,f) over an equivalent neutron energy range from 0 to 20 MeV using the Surrogate Ratio method. A 55 MeV {sup 4}He beam from the 88 Inch Cyclotron at Lawrence Berkeley National Laboratory was used to induce fission in the following reactions: {sup 238}U({alpha},{alpha}{prime}f) and {sup 236}U({alpha},{alpha}{prime}f). The {sup 238}U reaction was a surrogate for {sup 237}U(n,f) and the {sup 236}U reaction was used as a surrogate for {sup … more
Date: December 29, 2005
Creator: Burke, J. T.; Bernstein, L. A.; Escher, J.; Ahle, L.; Church, J. A.; Dietrich, F. S. et al.
Partner: UNT Libraries Government Documents Department
open access

Nuclear Physics from Scratch

Description: We report on applications of the ab initio, no-core shell model with the primary goal of achieving an accurate description of nuclear structure and reactions from the fundamental inter-nucleon interactions. We show that realistic two-nucleon interactions are inadequate to describe the low-lying structure of {sup 10}B, and that realistic three-nucleon interactions are essential. We report preliminary attempts to compute astrophysical S-factors
Date: April 29, 2005
Creator: Ormand, W; Navratil, P; Forssen, C & Bertulani, C
Partner: UNT Libraries Government Documents Department
open access

Shift Dependent Skew Quadrupole in Advanced Light SourceElliptically Polarizing Undulators, Cause and Corrections

Description: Three elliptically polarizing undulators (EPU) are installed and operational at the Advanced Light Source (ALS); the most recent was installed in April 2005. Operational experience has shown a variation in electron beam size which correlates with the EPU's magnetic quadrant shifts used to vary polarization. Storage ring electron dynamics studies pointed to the existence of a shift dependent skew quadrupole (SQ) component generated within the EPUs. Detailed magnetic and mechanical measurements d… more
Date: November 29, 2005
Creator: Marks, Steve; Prestemon, Soren; Robin, David; Schlueter, Ross D.; Steier, Christoph; Wolski, Andrew et al.
Partner: UNT Libraries Government Documents Department
open access

Charm Physics at BaBar

Description: Large production of the c{bar c} pairs and high integrated luminosity make the PEPII B Factory an excellent place for studying the charm hadrons. In this paper, we present a few most recent results from BaBar collaboration in charm sector.
Date: June 29, 2005
Creator: Chen, Chunhui
Partner: UNT Libraries Government Documents Department
open access

Comparison of Design and Practices for Radiation Safety among Five Synchrotron Radiation Facilities

Description: There are more and more third-generation synchrotron radiation (SR) facilities in the world that utilize low emittance electron (or positron) beam circulating in a storage ring to generate synchrotron light for various types of experiments. A storage ring based SR facility consists of an injector, a storage ring, and many SR beamlines. When compared to other types of accelerator facilities, the design and practices for radiation safety of storage ring and SR beamlines are unique to SR facilitie… more
Date: June 29, 2005
Creator: Liu, James C.; Rokni, Sayed H.; Asano, Yoshihiro; Casey, William R. & Donahue, Richard J.
Partner: UNT Libraries Government Documents Department
open access

Measurement of the B+- --> rho+- pi0 Branching Fraction and Direct CP Asymmetry

Description: An improved measurement of the process B{sup {+-}} {yields} {rho}{sup {+-}}{pi}{sup 0} is presented. The data sample of 211 fb{sup -1} comprises 232 million {Upsilon}(4S) {yields} B{bar B} decays collected with the BABAR detector at the PEP-II asymmetric B Factory at SLAC. The yield and CP asymmetry are calculated using an extended maximum likelihood fitting method. The branching fraction and asymmetry are found to be {Beta}(B{sup {+-}} {yields} {rho}{sup {+-}}{pi}{sup 0}) = [10.0 {+-} 1.4 (Sta… more
Date: June 29, 2005
Creator: Aubert, B.; Barate, R.; Boutigny, D.; Couderc, F.; Karyotakis, Y.; Lees, J. P. et al.
Partner: UNT Libraries Government Documents Department
open access

Kinetics of carboplatin-DNA binding in genomic DNA and bladder cancer cells as determined by accelerator mass spectrometry

Description: Cisplatin and carboplatin are platinum-based drugs that are widely used in cancer chemotherapy. The cytotoxicity of these drugs is mediated by platinum-DNA monoadducts and intra- and interstrand diadducts, which are formed following uptake of the drug into the nucleus of cells. The pharmacodynamics of carboplatin display fewer side effects than for cisplatin, albeit with less potency, which may be due to differences in rates of DNA adduct formation. We report the use of accelerator mass spectro… more
Date: December 29, 2005
Creator: Hah, S S; Stivers, K M; Vere White, R & Henderson, P T
Partner: UNT Libraries Government Documents Department
open access

Band Structure Parameters and Fermi Resonances of Exciton-Polaritons in CsI and CsBr under Hydrostatic Pressure

Description: Most alkali halides crystallize in the fcc sodium chloride structure. In contrast, with the exception of CsF, the Cs-halides form the simple cubic cesium chloride (CsCl) structure at ambient conditions and they have a substantially different electronic structure than other alkali halides; in particular, they have several nearly degenerate electronic levels near the Brillouin zone center. Highly resolved Three-Photon Spectroscopy (TPS) measurements allow direct observation of the near band edge … more
Date: November 29, 2005
Creator: Lipp, M J; Yoo, C H; Strachan, D & Daniels, W B
Partner: UNT Libraries Government Documents Department
open access

MICRON-SCALE DEEP HOLE DRILLING FOR BERYLLIUM CAPSULE FILL APPLICATIONS

Description: A laser processing system has been developed to drill high aspect ratio holes through the impermeable beryllium capsules envisioned for ignition shots on NIF. The drilling system was designed to produce holes with an entrance and exit diameter of approximately 5 {micro}m through the full 175 {micro}m thickness of the capsule. To meet these requirements, a frequency doubled femtosecond-class Ti:Sapphire laser is directed through a high numerical aperture lens to provide the spot geometry needed … more
Date: November 29, 2005
Creator: Armstrong, J P; Rubenchik, A M; Gunther, J & Stuart, B C
Partner: UNT Libraries Government Documents Department
open access

Image Correlation Applied to Single Crystal Plasticity Experiments and Comparison to Strain Gage Data

Description: Full-field optical techniques are becoming increasingly popular for measuring the deformation of materials, especially in materials that exhibit non-uniform behavior. While there are many full-field techniques available (e.g. moire interferometry, electronic speckle pattern interferometry (ESPI), holography, and image correlation [1]), for our study of the deformation of single crystals, the image correlation technique was chosen for its insensitivity to vibrations and ability to measure large … more
Date: June 29, 2005
Creator: LeBlanc, M. M.; Florando, J. N.; Lassila, D. H.; Schmidt, T. & Tyson, J., II
Partner: UNT Libraries Government Documents Department
open access

Hands-on lessons in ergonomics for youth

Description: Ergonomics risk factors apply to everybody. Numerous adults have experienced disabling injuries related to use of computers and other forms of technology. Now children are using technology even more than adults. Increasingly ergonomics risk factors are being recognized as present in the world of children. Outreach to schools and the surrounding community by employers may help protect the future work force. A growing body of researchers believe that children can benefit from the early introducti… more
Date: September 29, 2005
Creator: Bennett, C; Alexandre, M & Jacobs, K
Partner: UNT Libraries Government Documents Department
open access

Russian Military and Security Forces: A Postulated Reaction to a Nuclear Detonation

Description: In this paper, we will examine how Russia's military and security forces might react to the detonation of a 10-kiloton nuclear weapon placed next to the walls surrounding the Kremlin. At the time of this 'big bang,' Putin is situated outside Moscow and survives the explosion. No one claims responsibility for the detonation. No other information is known. Numerous variables will determine how events ultimately unfold and how the military and security forces will respond. Prior to examining these… more
Date: April 29, 2005
Creator: Ball, D
Partner: UNT Libraries Government Documents Department
open access

Quantum-based Atomistic Simulation of Transition Metals

Description: First-principles generalized pseudopotential theory (GPT) provides a fundamental basis for transferable multi-ion interatomic potentials in d-electron transition metals within density-functional quantum mechanics. In mid-period bcc metals, where multi-ion angular forces are important to structural properties, simplified model GPT or MGPT potentials have been developed based on canonical d bands to allow analytic forms and large-scale atomistic simulations. Robust, advanced-generation MGPT poten… more
Date: August 29, 2005
Creator: Moriarty, J A; Benedict, L X; Glosli, J N; Hood, R Q; Orlikowski, D A; Patel, M V et al.
Partner: UNT Libraries Government Documents Department
open access

A Stringy Test of Flux-Induced Isometry Gauging

Description: Supergravity analysis suggests that the effect of fluxes in string theory compactifications is to gauge isometries of the scalar manifold. However, isometries are generically broken by brane instanton effects. Here we demonstrate how fluxes protect exactly those isometries from quantum corrections which are gauged according to the classical supergravity analysis. We also argue that all other isometries are generically broken.
Date: June 29, 2005
Creator: Kashani-Poor, Amir-Kian & Tomasiello, Alessandro
Partner: UNT Libraries Government Documents Department
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