Eclipsing binary stars in the Large and Small Magellanic Clouds from the MACHO project: The Sample (open access)

Eclipsing binary stars in the Large and Small Magellanic Clouds from the MACHO project: The Sample

We present a new sample of 4634 eclipsing binary stars in the Large Magellanic Cloud (LMC), expanding on a previous sample of 611 objects and a new sample of 1509 eclipsing binary stars in the Small Magellanic Cloud (SMC), that were identified in the light curve database of the MACHO project. We perform a cross correlation with the OGLE-II LMC sample, finding 1236 matches. A cross correlation with the OGLE-II SMC sample finds 698 matches. We then compare the LMC subsamples corresponding to center and the periphery of the LMC and find only minor differences between the two populations. These samples are sufficiently large and complete that statistical studies of the binary star populations are possible.
Date: March 29, 2007
Creator: Faccioli, L.; Alcock, C.; Cook, K.; Prochter, G.; Protopapas, P. & Syphers, D.
Object Type: Article
System: The UNT Digital Library
Results of the 2h Evaporator Acid Cleaning and in-Pot Neutralization (open access)

Results of the 2h Evaporator Acid Cleaning and in-Pot Neutralization

The estimated 200 gallons of sodium aluminosilicate scale (NAS) present in the 242-16H Evaporator pot prior to chemical cleaning was subjected to four batches of 1.5 M (9 wt%) nitric acid. Each batch was neutralized with 19 M (50 wt %) sodium hydroxide (caustic) before transfer to Tank 38. The chemical cleaning process began on November 20, 2006, and was terminated on December 10, 2006. An inspection of the pot's interior was performed and based on data gathered during that inspection; the current volume of scale in the pot is conservatively estimated to be 36.3 gallons, which is well below the 200 gallon limit specified in the Technical Safety Requirements. In addition, the performance during all aspects of cleaning agreed well with the flowsheet developed at the bench and pilot scale. There were some lessons learned during the cleaning outage and are detailed in appendices of this report.
Date: May 29, 2007
Creator: Wilmarth, B.; Phillip Norris, P. & Terry Allen, T.
Object Type: Report
System: The UNT Digital Library
A Compact Linac for Proton Therapy Based on a Dielectric Wall Accelerator (open access)

A Compact Linac for Proton Therapy Based on a Dielectric Wall Accelerator

A novel compact CT-guided intensity modulated proton radiotherapy (IMPT) system is described. The system is being designed to deliver fast IMPT so that larger target volumes and motion management can be accomplished. The system will be ideal for large and complex target volumes in young patients. The basis of the design is the dielectric wall accelerator (DWA) system being developed at the Lawrence Livermore National Laboratory (LLNL). The DWA uses fast switched high voltage transmission lines to generate pulsed electric fields on the inside of a high gradient insulating (HGI) acceleration tube. High electric field gradients are achieved by the use of alternating insulators and conductors and short pulse times. The system will produce individual pulses that can be varied in intensity, energy and spot width. The IMPT planning system will optimize delivery characteristics. The system will be capable of being sited in a conventional linac vault and provide intensity modulated rotational therapy. Feasibility tests of an optimization system for selecting the position, energy, intensity and spot size for a collection of spots comprising the treatment are underway. A prototype is being designed and concept designs of the envelope and environmental needs of the unit are beginning. The status of …
Date: October 29, 2007
Creator: Caporaso, G. J.; Mackie, T. R.; Sampayan, S.; Chen, Y.; Wang, L.; Blackfield, D. et al.
Object Type: Article
System: The UNT Digital Library
TREATABILITY TEST FOR REMOVING TECHNETIUM-99 FROM 200-ZP-1 GROUNDWATER HANFORD SITE (open access)

TREATABILITY TEST FOR REMOVING TECHNETIUM-99 FROM 200-ZP-1 GROUNDWATER HANFORD SITE

The 200-ZP-1 Groundwater Operable Unit (OU) is one of two groundwater OUs located within the 200 West groundwater aggregate area of the Hanford Site. The primary risk-driving contaminants within the 200-ZP-1 OU include carbon tetrachloride and technetium-99 (Tc-99). A pump-and-treat system for this OU was initially installed in 1995 to control the 0.002 kg/m{sup 3} (2000 {micro}g/L) contour of the carbon tetrachloride plume. Carbon tetrachloride is removed from groundwater with the assistance of an air-stripping tower. Ten extraction wells and three injection wells operate at a combined rate of approximately 0.017m{sup 3}/s (17.03 L/s). In 2005, groundwater from two of the extraction wells (299-W15-765 and 299-W15-44) began to show concentrations greater than twice the maximum contaminant level (MCL) of Tc-99 (33,309 beq/m{sup 3} or 900 pCi/L). The Tc-99 groundwater concentrations from all ten of the extraction wells when mixed were more than one-half of the MCL and were slowly increasing. If concentrations continued to rise and the water remained untreated for Tc-99, there was concern that the water re-injected into the aquifer could exceed the MCL standard. Multiple treatment technologies were reviewed for selectively removing Tc-99 from the groundwater. Of the treatment technologies, only ion exchange was determined to be …
Date: November 29, 2007
Creator: SW, PETERSEN; AC, TORTOSO; WS, ELLIOTT & ME, BYRNES
Object Type: Article
System: The UNT Digital Library
The Integration of Energy Efficiency, Renewable Energy, DemandResponse and Climate Change: Challenges and Opportunities for Evaluatorsand Planners (open access)

The Integration of Energy Efficiency, Renewable Energy, DemandResponse and Climate Change: Challenges and Opportunities for Evaluatorsand Planners

This paper explores the feasibility of integrating energyefficiency program evaluation with the emerging need for the evaluationof programs from different "energy cultures" (demand response, renewableenergy, and climate change). The paper reviews key features andinformation needs of the energy cultures and critically reviews theopportunities and challenges associated with integrating these withenergy efficiency program evaluation. There is a need to integrate thedifferent policy arenas where energy efficiency, demand response, andclimate change programs are developed, and there are positive signs thatthis integration is starting to occur.
Date: May 29, 2007
Creator: Vine, Edward
Object Type: Report
System: The UNT Digital Library
An Explicit Runge-Kutta Iteration for Diffusion in the Low MachNumber Combustion Code (open access)

An Explicit Runge-Kutta Iteration for Diffusion in the Low MachNumber Combustion Code

This report describes the implementation of a Runge-Kuttaiterationboth for mixture-averaged and for multicomponent diffusion withDufourand Soret effects in the low Mach number combustioncode.
Date: August 29, 2007
Creator: Grcar, Joseph F.
Object Type: Report
System: The UNT Digital Library
Annual Report of the International Nuclear Energy Research Initiative Osmose Project (FY06). (open access)

Annual Report of the International Nuclear Energy Research Initiative Osmose Project (FY06).

The goal of the OSMOSE program is to measure the reactivity effect of minor actinides in known neutron spectra of interest to the Generation-IV reactor program and other programs and to create a database of these results for use as an international benchmark for the minor actinides. The results are then compared to calculation models to verify and validate integral absorption cross-sections for the minor actinides. The OSMOSE program includes all aspects of the experimental program--including the fabrication of fuel pellets and samples, the oscillation of the samples in the MINERVE reactor for the measurement of the reactivity effect, reactor physics modeling of the MINERVE reactor, and the data analysis and interpretation of the experimental results.
Date: August 29, 2007
Creator: Klann, R. T.; Hudelot, J. P.; Drin, N.; Zhong, Z.; Division, Nuclear Engineering & Atomique, Commissariat a l'Energie
Object Type: Report
System: The UNT Digital Library
Highly Potent, Water Soluble Benzimidazole Antagonist for Activated (alpha)4(beta)1 Integrin (open access)

Highly Potent, Water Soluble Benzimidazole Antagonist for Activated (alpha)4(beta)1 Integrin

The cell surface receptor {alpha}{sub 4}{beta}{sub 1} integrin, activated constitutively in lymphoma, can be targeted with the bisaryl urea peptidomimetic antagonist 1 (LLP2A). However, concerns on its preliminary pharmacokinetic (PK) profile provided an impetus to change the pharmacophore from a bisaryl urea to a 2-arylaminobenzimidazole moiety resulting in improved solubility while maintaining picomolar potency [5 (KLCA4); IC{sub 50} = 305 pM]. With exceptional solubility, this finding has potential for improving PK to help diagnose and treat lymphomas.
Date: August 29, 2007
Creator: Carpenter, R. D.; Andrei, M.; Lau, E. Y.; Lightstone, F. C.; Liu, R.; Lam, K. S. et al.
Object Type: Article
System: The UNT Digital Library
SYSTEMATIC STUDIES OF HEAVY ION COLLISIONS TO SEARCH FOR QUARK-GLUON PLASMA (open access)

SYSTEMATIC STUDIES OF HEAVY ION COLLISIONS TO SEARCH FOR QUARK-GLUON PLASMA

This is the final technical report for DOE Outstanding Junior Investigator (OJI) Award, 'Systematic Studies of Heavy Ion Collisions to Search for Quark-Gluon Plasma', grant DE-FG02-02ER41219, Principal Investigator (PI) Fuqiang Wang. The research under the grant was divided into two phases. The first concentrated on systematic studies of soft hadron production at low transverse momentum (p{sub T}), in particular the production of (anti-)baryon and strangeness in heavy ion collisions at RHIC energies. The second concentrated on measurements of di-hadron and multi-hadron jet-correlations and investigations of medium response to jets. The research was conducted at the Relativistic Heavy-Ion Collider (RHIC) at BNL with the Solenoidal Tracker At RHIC (STAR) experiment. The total grant is $214,000. The grant established a PC farm solely used for this research. The PC farm consists of 8 nodes with a total of 16 CPUs and 3 disk servers of total 2 TB shared storage. The current balance of the grant is $19,985. The positive balance is because an initial purchase of $22,600 for the PC farm came out of the PI's start-up fund due to the lateness of the award. The PC farm is an integral part of the Purdue Physics Department's computer cluster. The grant …
Date: November 29, 2007
Creator: Wang, Fuqiang
Object Type: Report
System: The UNT Digital Library
X-Ray Active Matrix Pixel Sensors Basedon J-FET Technology Developed for the Linac Coherent Light Source. (open access)

X-Ray Active Matrix Pixel Sensors Basedon J-FET Technology Developed for the Linac Coherent Light Source.

An X-ray Active Matrix Pixel Sensor (XAMPS) is being developed for recording data for the X-ray Pump Probe experiment at the Linac Coherent Light Source (LCLS). Special attention has to be paid to some technological challenges that this design presents. New processes were developed and refined to address problems encountered during previous productions of XAMPS. The development of these critical steps and corresponding tests results are reported here.
Date: October 29, 2007
Creator: Carini, G. A.; Chen, W.; Li, Z.; Rehak, P. & Siddons, D. P.
Object Type: Article
System: The UNT Digital Library
Sensitivity and representativity analysis of past experiments with respect to ABTR system. (open access)

Sensitivity and representativity analysis of past experiments with respect to ABTR system.

A comprehensive validation analysis has been performed that incorporates representativity of multiple parameters, experiments, reference designs, and adjustment of the nuclear data. The work involves a new representativity study among selected reactor designs and several experiments. Application, using existing experiments, to reference design like the ABTR and the SFR has demonstrated that it is possible to achieve a significant reduction of uncertainty on the main integral parameters of interest for their neutronic design. This is possible when the set of available experiments are relevant (i.e. representative of the reference designs), of good quality (i.e. of reduced uncertainty on experimental results), and consistent (i.e. not providing conflictive information).
Date: August 29, 2007
Creator: Aliberti, G.; Palmiotti, G. & Salvatores, M.
Object Type: Report
System: The UNT Digital Library
Compact Analytic Expression for the Electric Field of a 2DElliptical Charge Distribution Inside a Perfectly Conducting CircularCylinder (open access)

Compact Analytic Expression for the Electric Field of a 2DElliptical Charge Distribution Inside a Perfectly Conducting CircularCylinder

By combining the method of images with calculus of complex variables, we provide a simple expression for the electric field of a two-dimensional (2D) static elliptical charge distribution inside a perfectly conducting cylinder. The charge distribution need not be concentric with the cylinder.
Date: May 29, 2007
Creator: Furman, M. A.
Object Type: Article
System: The UNT Digital Library
In-situ X-ray photoelectron spectroscopy studies of water on metals and oxides at ambient conditions (open access)

In-situ X-ray photoelectron spectroscopy studies of water on metals and oxides at ambient conditions

X-ray photoelectron spectroscopy (XPS) is a powerful tool for surface and interface analysis, providing the elemental composition of surfaces and the local chemical environment of adsorbed species. Conventional XPS experiments have been limited to ultrahigh vacuum (UHV) conditions due to a short mean free path of electrons in a gas phase. The recent advances in instrumentation coupled with third-generation synchrotron radiation sources enables in-situ XPS measurements at pressures above 5 Torr. In this review, we describe the basic design of the ambient pressure XPS setup that combines differential pumping with an electrostatic focusing. We present examples of the application of in-situ XPS to studies of water adsorption on the surface of metals and oxides including Cu(110), Cu(111), TiO2(110) under environmental conditions of water vapor pressure. On all these surfaces we observe a general trend where hydroxyl groups form first, followed by molecular water adsorption. The importance of surface OH groups and their hydrogen bonding to water molecules in water adsorption on surfaces is discussed in detail.
Date: October 29, 2007
Creator: Salmeron, Miquel; Yamamoto, S.; Bluhm, H.; Andersson, K.; Ketteler, G.; Ogasawara, H. et al.
Object Type: Article
System: The UNT Digital Library
Monochromatic Electron Photoemission from Diamondoid Monolayers (open access)

Monochromatic Electron Photoemission from Diamondoid Monolayers

None
Date: May 29, 2007
Creator: Yang, W. L.; Fabbri, J. D.; Willey, T. M.; Lee, J. I.; Dahl, J. E.; Carlson, R. K. et al.
Object Type: Article
System: The UNT Digital Library
Neutron Capture gamma ENDF libraries for modeling and identification of neutron sources (open access)

Neutron Capture gamma ENDF libraries for modeling and identification of neutron sources

There are a number of inaccuracies and data omissions with respect to gammas from neutron capture in the ENDF libraries used as field reference information and by modeling codes used in JTOT. As the use of Active Neutron interrogation methods is expanded, these shortfalls become more acute. A new, more accurate and complete evaluated experimental database of gamma rays (over 35,000 lines for 262 isotopes up to U so far) from thermal neutron capture has recently become available from the IAEA. To my knowledge, none of this new data has been installed in ENDF libraries and disseminated. I propose to upgrade libraries of {sup 184,186}W, {sup 56}Fe, {sup 204,206,207}Pb, {sup 104}Pd, and {sup 19}F the 1st year. This will involve collaboration with Richard Firestone at LBL in evaluating the data and installing it in the libraries. I will test them with the transport code MCNP5.
Date: October 29, 2007
Creator: Sleaford, B
Object Type: Report
System: The UNT Digital Library
SALT CORE SAMPLING EVOLUTION AT THE SAVANNAH RIVER SITE (open access)

SALT CORE SAMPLING EVOLUTION AT THE SAVANNAH RIVER SITE

The Savannah River Site (SRS), a Department of Energy (DOE) facility, has over 30 million gallons of legacy waste from its many years of processing nuclear materials. The majority of waste is stored in 49 buried tanks. Available underground piping is the primary and desired pathway to transfer waste from one tank to another until the waste is delivered to the glass plant, DWPF, or the grout plant, Saltstone. Prior to moving the material, the tank contents need to be evaluated to ensure the correct destination for the waste is chosen. Access ports are available in each tank top in a number of locations and sizes to be used to obtain samples of the waste for analysis. Material consistencies vary for each tank with the majority of waste to be processed being radioactive salts and sludge. The following paper describes the progression of equipment and techniques developed to obtain core samples of salt and solid sludge at SRS.
Date: November 29, 2007
Creator: Nance, T; Daniel Krementz, D & William Cheng, W
Object Type: Article
System: The UNT Digital Library
Surface Specularity as an Indicator of Shock-Induced Solid-Liquid Phase Transitions (open access)

Surface Specularity as an Indicator of Shock-Induced Solid-Liquid Phase Transitions

When highly polished metal surfaces melt upon release after shock loading, they exhibit a number of features that suggest that significant surface changes accompany the phase transition. The reflection of light from such surfaces changes from specular (pre-shock) to diffuse upon melting. A familiar manifestation of this phenomenon is the loss of signal light in velocimetric measurements typically observed above pressures high enough to melt the free-surface. Unlike many other potential material phase-sensitive diagnostics (e.g., reflectometery, conductivity), changes in the specularity of reflection provide a dramatic, sensitive indicator of the solid-liquid phase transition. Data will be presented from multiple diagnostics that support the hypothesis that specularity changes indicate melt. These diagnostics include shadowgraphy, infrared imagery, high-magnification surface images, interferometric velocimetry, and most recently scattering angle measurements.
Date: June 29, 2007
Creator: Gerald Stevens, Stephen Lutz, William Turley, Lynn Veeser
Object Type: Article
System: The UNT Digital Library
Argonne National Laboratory Summary Site Environmental Report for Calendar Year 2005. (open access)

Argonne National Laboratory Summary Site Environmental Report for Calendar Year 2005.

None
Date: May 29, 2007
Creator: Golchert, N. W.
Object Type: Report
System: The UNT Digital Library
Effect of Random Clustering on Surface Damage Density Estimates (open access)

Effect of Random Clustering on Surface Damage Density Estimates

Identification and spatial registration of laser-induced damage relative to incident fluence profiles is often required to characterize the damage properties of laser optics near damage threshold. Of particular interest in inertial confinement laser systems are large aperture beam damage tests (>1cm{sup 2}) where the number of initiated damage sites for {phi}>14J/cm{sup 2} can approach 10{sup 5}-10{sup 6}, requiring automatic microscopy counting to locate and register individual damage sites. However, as was shown for the case of bacteria counting in biology decades ago, random overlapping or 'clumping' prevents accurate counting of Poisson-distributed objects at high densities, and must be accounted for if the underlying statistics are to be understood. In this work we analyze the effect of random clumping on damage initiation density estimates at fluences above damage threshold. The parameter {psi} = a{rho} = {rho}/{rho}{sub 0}, where a = 1/{rho}{sub 0} is the mean damage site area and {rho} is the mean number density, is used to characterize the onset of clumping, and approximations based on a simple model are used to derive an expression for clumped damage density vs. fluence and damage site size. The influence of the uncorrected {rho} vs. {phi} curve on damage initiation probability predictions is …
Date: October 29, 2007
Creator: Matthews, M J & Feit, M D
Object Type: Article
System: The UNT Digital Library
Inelastic final-state interaction (open access)

Inelastic final-state interaction

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"Watson's theorem" 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
Object Type: Article
System: The UNT Digital Library
Downstream Intensification Effects Associated with CO2 Laser Mitigation of Fused Silica (open access)

Downstream Intensification Effects Associated with CO2 Laser Mitigation of Fused Silica

Mitigation of 351nm laser-induced damage sites on fused silica exit surfaces by selective CO{sub 2} treatment has been shown to effectively arrest the exponential growth responsible for limiting the lifetime of optics in high-fluence laser systems. However, the perturbation to the optical surface profile following the mitigation process introduces phase contrast to the beam, causing some amount of downstream intensification with the potential to damage downstream optics. Control of the laser treatment process and measurement of the associated phase modulation is essential to preventing downstream 'fratricide' in damage-mitigated optical systems. In this work we present measurements of the surface morphology, intensification patterns and damage associated with various CO{sub 2} mitigation treatments on fused silica surfaces. Specifically, two components of intensification pattern, one on-axis and another off-axis can lead to damage of downstream optics and are related to rims around the ablation pit left from the mitigation process. It is shown that control of the rim structure around the edge of typical mitigation sites is crucial in preventing damage to downstream optics.
Date: October 29, 2007
Creator: Matthews, M. J.; Bass, I. L.; Guss, G. M.; Widmayer, C. C. & Ravizza, F. L.
Object Type: Article
System: The UNT Digital Library
Characterization of the Structure of Cation-DopedBacteriogenic Uranium Oxides using X-Ray Diffraction (open access)

Characterization of the Structure of Cation-DopedBacteriogenic Uranium Oxides using X-Ray Diffraction

Remediation of uranium contamination in subsurface groundwater has become imperative as previous research and manufacturing involving radionuclides has led to contamination of groundwater sources. A possible in situ solution for sequestration of uranium is a bacterial process in which Shewanella oneidensis MR-1 reduces the soluble (and thus mobile) U(VI) oxidation state into the less mobile UO{sub 2} crystalline phase. However, the long term stability of the UO2 compound must be studied as oxidative conditions could return it back into the U(VI) state. Incorporation of other cations into the structure during manufacture of the UO{sub 2} could alter the dissolution behavior. A wide angle x-ray scattering (WAXS) experiment was performed to determine whether or not calcium, manganese, and magnesium are incorporated into this structure. If so, the substituted atoms would cause a contraction or expansion in the lattice because of their differing size, causing the lattice constant to be altered. After several stages of data reduction, the WAXS diffraction peaks were fit using the Le Bail fit method in order to determine the lattice constant. Initial results suggest that there may be incorporation of manganese into the UO{sub 2} structure due to a .03 Angstrom decrease in lattice constant, but more …
Date: August 29, 2007
Creator: Stahlman, Jonathan M. & /SLAC, /Carnegie Mellon U.
Object Type: Report
System: The UNT Digital Library
Growth of laser damage in fused silica: diameter to depth ratio (open access)

Growth of laser damage in fused silica: diameter to depth ratio

Growth of laser initiated damage plays a major role in determining optics lifetime in high power laser systems. Previous measurements have established that the lateral diameter grows exponentially. Knowledge of the growth of the site in the propagation direction is also important, especially so when considering techniques designed to mitigate damage growth, where it is required to reach all the subsurface damage. In this work, we present data on both the diameter and the depth of a growing exit surface damage sites in fused silica. Measured growth rates with both 351 nm illumination and with combined 351 nm and 1054 nm illumination are discussed.
Date: October 29, 2007
Creator: Norton, M. A.; Adams, J. J.; Carr, C. W.; Donohue, E. E.; Feit, M. D.; Hackel, R. P. et al.
Object Type: Article
System: The UNT Digital Library
Dislocation-Radiation Obstacle Interactions: Developing Improved Mechanical Property Constitutive Models (open access)

Dislocation-Radiation Obstacle Interactions: Developing Improved Mechanical Property Constitutive Models

Radiation damage to structural and cladding materials, including austenitic stainless steels, ferritic steels, and zirconium alloys, in nuclear reactor environments results in significant mechanical property degradation, including yield strength increases, severe ductility losses and flow localization, which impacts reliability and performance. Generation IV and advanced fuel cycle concepts under consideration will require the development of advanced structural materials, which will operate in increasingly hostile environments. The development of predictive models is required to assess the performance and response of materials in extreme Gen IV reactor operating conditions (temperature, stress, and pressure), to decrease the time to rapidly assess the properties of new materials and insert them into technological applications (Gen IV and Advanced Fuel Cycle Operations).
Date: November 29, 2007
Creator: WIrth, B.D. & Robertson, Ian M.
Object Type: Report
System: The UNT Digital Library