A 14.6 Arcsecond Quasar Lens Split by a Massive Dark Matter Halo (open access)

A 14.6 Arcsecond Quasar Lens Split by a Massive Dark Matter Halo

Gravitational lensing is a powerful tool to study the distribution of dark matter in the universe. The cold dark matter model of structure formation predicts the existence of quasars gravitationally lensed by concentrations of dark matter so massive that the quasar images would be split by over 7 inches. However, numerous searches for large-separation lensed quasars have been unsuccessful; all of the roughly 70 lensed quasars known to date, such as Q0957+561, have smaller splittings, and can be explained in terms of galaxy scale concentrations of baryonic matter that have undergone dissipative collapse. Here they report the discovery of the first large-separation lensed quasar, SDSS J1004+4112, with a maximum separation of 14.62 inches; at this separation, the lensing object must be dominated by dark matter. While gravitationally lensed galaxies of even large separation are known, large-separation quasars are more useful cosmological probes because of the simplicity of the resulting lens systems. The discovery in their current quasar sample is fully consistent with the theoretical expectations based on the cold dark matter model.
Date: December 4, 2003
Creator: Inada, N.; Oguri, M.; Pindor, B.; Hennawi, J.; Chiu, K.; Zheng, W. et al.
Object Type: Article
System: The UNT Digital Library
Coup in Georgia [Republic]: Recent Developments and Implications (open access)

Coup in Georgia [Republic]: Recent Developments and Implications

This report examines the ouster of Georgia's President Eduard Shevardnadze in the wake of a legislative election that may Georgians viewed as not free and fair.
Date: December 4, 2003
Creator: Nichol, Jim
Object Type: Report
System: The UNT Digital Library
Development of a Novel Non-Consumable Anode for Electrowinning Primary Aluminum (open access)

Development of a Novel Non-Consumable Anode for Electrowinning Primary Aluminum

The principal goal of the project was to determine through theoretical considerations and from chemical and electrochemical laboratory studies the technical and economic feasibility for the substitution and retrofitting of an SOFC-type anode for today's carbon anode in a cell for electrowinning primary Al. However, solubility measurements showed that no value of cryolite ratio can exist where the solubilities of the solid electrolyte components (zirconia and especially yttria) would be small relative to the alumina solubility. Therefore, the utilization of the proposed SOFC-type anode cannot be realized for any cell involving a cryolite-base solvent. However, the project suggested that the SOFC-type anode scheme might be successful if the solvent/electrolyte for electrowinning Al could be changed to a fused sulfate melt. During the solubility experiments, electrochemical probes were developed, and a bath characterization was defined, to measure quantitatively the acid-base character of cryolite melts. The measured acid-base behavior was then used to correlate the alumina solubility in cryolite over a wide range of cryolite ratio at 1300K. A mathematical modeling of the alumina solubility as a function of basicity identified three solutes of Al{sub 2}O{sub 3} in cryolite-base melts: Na{sub 2}Al{sub 2}OF{sub 6}, Na{sub 2}Al{sub 2}O{sub 2}F{sub 4}, and Na{sub 4}Al{sub …
Date: December 4, 2003
Creator: Rapp, Robert A. & Zhang, Y.
Object Type: Report
System: The UNT Digital Library
Effects of the Use of Pore Formers on Performance of an Anode supported Solid Oxide Fuel Cell (open access)

Effects of the Use of Pore Formers on Performance of an Anode supported Solid Oxide Fuel Cell

The effects of amount of pore former used to produce porosity in the anode of an anode supported planar solid oxide fuel cell were examined. The pore forming material utilized was rice starch. The reduction rate of the anode material was measured by Thermogravimetric Analysis (TGA) to qualitatively characterize the gas transport within the porous anode materials. Fuel cells with varying amounts of porosity produced by using rice starch as a pore former were tested. The performance of the fuel cell was the greatest with an optimum amount of pore former used to create porosity in the anode. This optimum is believed to be related to a trade off between increasing gas diffusion to the active three-phase boundary region of the anode and the loss of performance due to the replacement of active three-phase boundary regions of the anode with porosity.
Date: December 4, 2003
Creator: Haslam, J. J.; Pham, A.; Chung, B. W.; DiCarlo, J. F. & Glass, R. S.
Object Type: Article
System: The UNT Digital Library
Evaporative Concentration of 100x J13 Ground Water at 60% Relative Humidity and 90C (open access)

Evaporative Concentration of 100x J13 Ground Water at 60% Relative Humidity and 90C

In these experiments we studied the behavior of a synthetic concentrated J13 solution as it comes in contact with a Ni-Cr-Mo-alloy selected for waste canisters in the designated high-level nuclear-waste repository at Yucca Mountain, Nevada. Concentrated synthetic J13 solution was allowed to drip slowly onto heated test specimens (90 C, 60% relative humidity) where the water moved down the surface of the specimens, evaporated and minerals precipitated. Mineral separation or zoning along the evaporation path was not observed. We infer from solid analyses and geochemical modeling, that the most corrosive components (Ca, Mg, and F) are limited by mineral precipitation. Minerals identified by x-ray diffraction include thermonatrite, natrite, and trona, all sodium carbonate minerals, as well as kogarkoite (Na{sub 3}SO{sub 4}F), halite (NaCl), and niter (KNO{sub 3}). Calcite and a magnesium silicate precipitation are based on chemical analyses of the solids and geochemical modeling. The most significant finding of this study is that sulfate and fluoride concentrations are controlled by the solubility of kogarkoite. Kogarkoite thermodynamic data are needed in the Yucca Mountain Project database to predict the corrosiveness of carbonate brines and to establish the extent to which fluoride is removed from the brines as a solid.
Date: December 4, 2003
Creator: Staggs, K; Maureen Alai,; Hailey, P; Carroll, S A; Sutton, M & Nguyen, Q A
Object Type: Report
System: The UNT Digital Library
Field Analysis of Propellant Stabilizers and their Daughter Products in any Propellant Formulation by Thin-Layer Chromatography Year End Report 2003 (open access)

Field Analysis of Propellant Stabilizers and their Daughter Products in any Propellant Formulation by Thin-Layer Chromatography Year End Report 2003

Lawrence Livermore National Laboratory's Forensic Science Center (FSC) has successfully resolved a variety of concerns related to propellant stabilizer analysis by thin-layer chromatography. The technology is now ready to proceed to validation and the related issues associated with deployment, both CONUS and OCONUS. The goal of this project is to develop a completely self-contained field-portable system to quantitatively analyze propellants for their stabilizer content. Lawrence Livermore National Laboratory's Forensic Science Center (FSC) has taken an established technology, thin-layer chromatography (TLC), and developed new sampling protocols, unique hardware, and specialized chemistries for incorporation into a new field-portable TLC kit. Some of the advantages of this system are the ability to analyze several samples or lots simultaneously, very low detection limits, and field reliability when deployed, it will become an efficient, cost-effective method for the determination of the remaining effective stabilizer (%RES) in propellants. Due to its portability, ease of use, and low cost, this technology will be useful in a variety of CONUS and OCONUS analysis scenarios. The TLC technology development is sponsored by the US Army, Defense Ammunition Center (DAC). Patents on this technology have been awarded and the kit is now commercially available.
Date: December 4, 2003
Creator: Whipple, R
Object Type: Report
System: The UNT Digital Library
First results on neutrinoless double beta decay of Te-130 with the calorimetric cuoricino experiment (open access)

First results on neutrinoless double beta decay of Te-130 with the calorimetric cuoricino experiment

The first results are reported on the limit for neutrinoless double decay of {sup 130}Te obtained with the new bolometric experiment CUORICINO. The set-up consists of 44 cubic crystals of natural TeO{sub 2}, 5 cm on the side and 18 crystals of 3 x 3 x 6 cm{sup 3}. Four of these latter crystals are made with isotopically enriched materials: two in {sup 128}Te and two others in {sup 130}Te . With a sensitive mass of {approx}40 kg, our array is by far the most massive running cryogenic detector to search for rare events. The array is operated at a temperature of {approx}10 mK in a dilution refrigerator under a heavy shield in the Gran Sasso Underground Laboratory at a depth of about 3500 m.w.e. The counting rate in the region of neutrinoless double beta decay is {approx}0.2 counts keV{sup -1} kg{sup -1} year{sup -1}, among the lowest in this type of experiment. No evidence for neutrinoless double beta decay is found with the present statistics obtained in about three months with a live time of 72%. The corresponding lower limit for the lifetime of this process is of 5.5 x 10{sup 23} years at 90% C.L. The corresponding limit …
Date: December 4, 2003
Creator: Arnaboldi, C.; Artusa, D. R.; Avignone, F. T.; Balata, M.; Bandac, I.; Barucci, M. et al.
Object Type: Article
System: The UNT Digital Library
Head Start: Better Data and Processes Needed to Monitor Underenrollment (open access)

Head Start: Better Data and Processes Needed to Monitor Underenrollment

A letter report issued by the General Accounting Office with an abstract that begins "Head Start, created in 1965, is designed to prepare low-income preschool children for school by providing a comprehensive set of early child development services primarily through communitybased organizations. Over the last decade there have been a number of changes in Head Start's operating environment, including a decrease in the number of poor children; an increase in the number, size, and scope of other federal and state early childhood programs; and an expansion in Head Start spending and enrollment. Given this environment, GAO was asked to determine (1) what is known about the extent to which Head Start programs are underenrolled, (2) ACF regional officials' and Head Start grantees' views on what factors contribute to underenrollment, and (3) what actions ACF and grantees have taken to address underenrollment."
Date: December 4, 2003
Creator: United States. General Accounting Office.
Object Type: Report
System: The UNT Digital Library
The House's Corrections Calendar (open access)

The House's Corrections Calendar

This report discusses the establishment of the "Corrections Day," a concept credited to Michigan Governor John Englerwhich, which is a procedure for repealing "the dumbest things the federal government is currently doing."
Date: December 4, 2003
Creator: Oleszek, Walter J.
Object Type: Report
System: The UNT Digital Library
Interferometric Studies of Laser-Created Plasmas Using Compact Soft X-Ray Lasers (open access)

Interferometric Studies of Laser-Created Plasmas Using Compact Soft X-Ray Lasers

We summarize results of several successful dense plasma diagnostics experiments realized by combining two different kinds of table-top soft x-ray lasers with an amplitude division interferometer based on diffraction grating beam splitters. In the first set of experiments this robust high throughput diffraction grating interferometer (DGI) was used with a 46.9 nm portable capillary discharge laser to study the dynamics of line focus and point focus laser-created plasmas. The measured electron density profiles, which differ significantly from those expected from a classical expansion, unveil important two-dimensional effects of the dynamics of these plasmas. A second DGI customized to operate in combination with a 14.7 nm Ni-like Pd transient gain laser was used to perform interferometry of line focus laser-created plasmas with picosecond time resolution. These measurements provide valuable new benchmarks for complex hydrodynamic codes and help bring new understanding of the dynamics of dense plasmas. The instrumentation and methodology we describe is scalable to significantly shorter wavelengths, and constitutes a promising scheme for extending interferometry to the study of very dense plasmas such as those investigated for inertial confinement fusion.
Date: December 4, 2003
Creator: Dunn, J.; Nilsen, J.; Moon, S.; Keenan, R.; Jankowska, E.; Maconi, M. C. et al.
Object Type: Article
System: The UNT Digital Library
Lithium Pellet Injector Development for NSTX (open access)

Lithium Pellet Injector Development for NSTX

A pellet injector suitable for the injection of lithium and other low-Z pellets of varying mass into plasmas at precise velocities from 5 to 500 m/s is being developed for use on NSTX (National Spherical Torus Experiment). The ability to inject low-Z impurities will significantly expand NSTX experimental capability for a broad range of diagnostic and operational applications. The architecture employs a pellet-carrying cartridge propelled through a guide tube by deuterium gas. Abrupt deceleration of the cartridge at the end of the guide tube results in the pellet continuing along its intended path, thereby giving controlled reproducible velocities for a variety of pellets materials and a reduced gas load to the torus. The planned injector assembly has four hundred guide tubes contained in a rotating magazine with eight tubes provided for injection into plasmas. A PC-based control system is being developed as well and will be described elsewhere in these Proceedings. The development path and mechanical performance of the injector will be described.
Date: December 4, 2003
Creator: Gettelfinger, G.; Dong, J.; Gernhardt, R.; Kugel, H.; Sichta, P. & Timberlake, J.
Object Type: Report
System: The UNT Digital Library
MICE -- Absorber and focus coil safety working group design document: Preliminary design and assessments (open access)

MICE -- Absorber and focus coil safety working group design document: Preliminary design and assessments

A Neutrino Factory based on a muon storage ring is the ultimate tool for studies of neutrino oscillations, including possibly the discovery of leptonic CP violation. it is also the first step toward a muon collider. To develop a stored-muon-beam facility to serve as a Neutrino Factory, it is necessary to ''cool'' a muon beam (decrease its phase-space volume). The short lifetime of the muon, 2.2 {micro}s at rest, eliminates all currently demonstrated cooling techniques and requires that a new, heretofore untried, technique--ionization cooling--be employed. Although ionization cooling of muons has never been demonstrated in practice, it has been shown by end-to-end simulation and design studies to be an important factor both for the performance and for the cost of a Neutrino Factory. This motivates an international program of R and D, including an experimental demonstration at Rutherford Appleton Laboratory (RAL). The aims of the international Muon Ionization Cooling Experiment are: (1) to show that it is possible to design, engineer and build a section of cooling channel capable of giving the desired performance for a Neutrino Factory; and (2) to place it in a muon beam and measure its performance in various modes of operation and beam conditions, thereby …
Date: December 4, 2003
Creator: Barr, Giles; Baynham, Elwyn; Black, Edgar; Bradshaw, Tom; Cummings, Mary Anne; Green, Michael A. et al.
Object Type: Report
System: The UNT Digital Library
The Overseas Private Investment Corporation: Background and Legislative Issues (open access)

The Overseas Private Investment Corporation: Background and Legislative Issues

None
Date: December 4, 2003
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Overview of the Medicare Prescription Drug and Reform Conference Agreement, H.R. 1 (open access)

Overview of the Medicare Prescription Drug and Reform Conference Agreement, H.R. 1

This report details the changes to Medicare that involves paying a monthly premium for a prescription drug benefit. It also includes either prices increases due to where one lives, or to reduce the amount offered in particular areas. Updated on December 4, 2003.
Date: December 4, 2003
Creator: O'Sullivan, Jennifer; Chaikind, Hinda; Tilson, Sibyl; Boulanger, Jennifer & Morgan, Paulette C.
Object Type: Report
System: The UNT Digital Library
Salaries of Federal Officials: A Fact Sheet (open access)

Salaries of Federal Officials: A Fact Sheet

This report provides a table presenting the salaries of federal officials and discusses salary adjustments between 1994 and 2004.
Date: December 4, 2003
Creator: Gressle, Sharon S.
Object Type: Report
System: The UNT Digital Library
Salaries of Federal Officials: A Fact Sheet (open access)

Salaries of Federal Officials: A Fact Sheet

None
Date: December 4, 2003
Creator: Gressle, Sharon S.
Object Type: Report
System: The UNT Digital Library
Sensitivity of Global Modeling Initiative CTM predictions of Antarctic ozone recovery to GCM and DAS generated meteorological fields (open access)

Sensitivity of Global Modeling Initiative CTM predictions of Antarctic ozone recovery to GCM and DAS generated meteorological fields

We use the Global Modeling Initiative chemistry and transport model to simulate the evolution of stratospheric ozone between 1995 and 2030, using boundary conditions consistent with the recent World Meteorological Organization ozone assessment. We compare the Antarctic ozone recovery predictions of two simulations, one driven by meteorological data from a general circulation model (GCM), the other using the output of a data assimilation system (DAS), to examine the sensitivity of Antarctic ozone recovery predictions to the characteristic dynamical differences between GCM and DAS-generated meteorological data. Although the age of air in the Antarctic lower stratosphere differs by a factor of 2 between the simulations, we find little sensitivity of the 1995-2030 Antarctic ozone recovery between 350 K and 650 K to the differing meteorological fields, particularly when the recovery is specified in mixing ratio units. Relative changes are smaller in the DAS-driven simulation compared to the GCM-driven simulation due to a surplus of Antarctic ozone in the DAS-driven simulation which is not consistent with observations. The peak ozone change between 1995 and 2030 in both simulations is {approx}20% lower than photochemical expectations, indicating that changes in ozone transport at 450 K between 1995 and 2030 constitute a small negative feedback. …
Date: December 4, 2003
Creator: Rotman, D & Bergmann, D
Object Type: Article
System: The UNT Digital Library
Space Acquisitions: Committing Prematurely to the Transformational Satellite Program Elevates Risks for Poor Cost, Schedule, and Performance Outcomes (open access)

Space Acquisitions: Committing Prematurely to the Transformational Satellite Program Elevates Risks for Poor Cost, Schedule, and Performance Outcomes

Correspondence issued by the General Accounting Office with an abstract that begins "In a multibillion-dollar effort, the Department of Defense (DOD) plans to build a space-based communications system that leverages technologies never before used in space. Such a system would enable DOD to transform how information is collected on potential U.S. adversaries and how military forces are warned of hostile action. The backbone of this system will be the Transformational Satellite (TSAT), which is expected to play a pivotal role in connecting communications networks on the ground, in the air, on ships, and in space. TSAT represents a potential leap forward in communications speed, security, and availability. The Air Force, which heads up DOD's space programs, intends for TSAT to be interoperable with similar systems being acquired for the National Aeronautics and Space Administration (NASA) and the intelligence agencies. The initial TSAT program is expected to cost about $12 billion from 2003 to 2015 for development and production. Several billions more are to be spent acquiring and supporting the associated ground infrastructure, including thousands of user terminals. The Air Force intends to start the acquisition program in December 2003 and expects to launch the first TSAT in 2011. To help …
Date: December 4, 2003
Creator: United States. General Accounting Office.
Object Type: Text
System: The UNT Digital Library
Telecommunications Discounts for Schools and Libraries: The “E-Rate” Program and Controversies (open access)

Telecommunications Discounts for Schools and Libraries: The “E-Rate” Program and Controversies

None
Date: December 4, 2003
Creator: unknown
Object Type: Report
System: The UNT Digital Library
The Advanced Light Source Upgrade (open access)

The Advanced Light Source Upgrade

The ALS, a third-generation synchrotron light source at Berkeley Lab, has been operating for almost a decade and is generating forefront science by exploiting the high brightness of a third-generation source in three areas: (1) high resolving power for spectroscopy; (2) high spatial resolution for microscopy and spectromicroscopy; and (3) high coherence for experiments such as speckle. However, the ALS was one of the first third-generation machines to be designed, and accelerator and insertion-device technology have significantly changed since its conception. As a result, its performance will inevitably be outstripped by newer, more advanced sources. To remain competitive and then set a new standard, the performance of the ALS, in particular its brightness, must be enhanced. Substantial improvements in brightness and current have always been feasible in principle, but they incur the penalty of a much reduced lifetime, which is totally unacceptable to our users. Significant brightness improvements can be realized in the core soft x-ray region by going to top-off operation, where injection would be quasi-continuous and the lifetime objections disappear. In top-off mode with higher average current, a reduced vertical emittance and beta function, and small-gap permanent-magnet or superconducting insertion devices, one to two orders of magnitude improvement …
Date: November 4, 2003
Creator: Chemla, Daniel S.; Feinberg, Benjamin; Hussain, Zahid; Krebs, Gary F.; Padmore, Howard A.; Robin, David S. et al.
Object Type: Article
System: The UNT Digital Library
Advanced Oxidation Process (open access)

Advanced Oxidation Process

The removal of recalcitrant sulfur species, dibenzothiophene and its derivatives, from automotive fuels is an integral component in the development of cleaner burning and more efficient automobile engines. Oxidative desulfurization (ODS) wherein the dibenzothiophene derivative is converted to its corresponding sulfoxide and sulfone is an attractive approach to sulfur removal because the oxidized species are easily extracted or precipitated and filtered from the hydrocarbon phase. Fe-TAML{reg_sign} activators of hydrogen peroxide (TAML is Tetra-Amido-Macrocyclic-Ligand) catalytically convert dibenzothiophene and its derivatives rapidly and effectively at moderate temperatures (50-60 C) and ambient pressure to the corresponding sulfoxides and sulfones. The oxidation process can be performed in both aqueous systems containing alcohols such as methanol, ethanol, or t-butanol, and in a two-phase hydrocarbon/aqueous system containing tert-butanol or acetonitrile. In the biphasic system, essentially complete conversion of the DBT to its oxidized products can be achieved using slightly longer reaction times than in homogeneous solution. Among the key features of the technology are the mild reaction conditions, the very high selectivity where no over oxidation of the sulfur compounds occurs, the near stoichiometric use of hydrogen peroxide, the apparent lack of degradation of sensitive fuel components, and the ease of separation of oxidized products.
Date: November 4, 2003
Creator: Horwitz, Colin P. & Collins, Terrence J.
Object Type: Report
System: The UNT Digital Library
Application of adaptive mesh refinement to particle-in-cell simulations of plasmas and beams (open access)

Application of adaptive mesh refinement to particle-in-cell simulations of plasmas and beams

Plasma simulations are often rendered challenging by the disparity of scales in time and in space which must be resolved. When these disparities are in distinctive zones of the simulation domain, a method which has proven to be effective in other areas (e.g. fluid dynamics simulations) is the mesh refinement technique. We briefly discuss the challenges posed by coupling this technique with plasma Particle-In-Cell simulations, and present examples of application in Heavy Ion Fusion and related fields which illustrate the effectiveness of the approach. We also report on the status of a collaboration under way at Lawrence Berkeley National Laboratory between the Applied Numerical Algorithms Group (ANAG) and the Heavy Ion Fusion group to upgrade ANAG's mesh refinement library Chombo to include the tools needed by Particle-In-Cell simulation codes.
Date: November 4, 2003
Creator: Vay, J. L.; Colella, P.; Kwan, J. W.; McCorquodale, P.; Serafini, D. B.; Friedman, A. et al.
Object Type: Article
System: The UNT Digital Library
A Cultural Resources Survey of Lakeview Pod A Adjacent to Timber Branch (open access)

A Cultural Resources Survey of Lakeview Pod A Adjacent to Timber Branch

A report of an archaeological survey of the proposed Lakeview Pod A development.
Date: November 4, 2003
Creator: Todd, Jesse E.
Object Type: Report
System: The Portal to Texas History
Election Reform and Electronic Voting Systems (DREs): Analysis of Security Issues (open access)

Election Reform and Electronic Voting Systems (DREs): Analysis of Security Issues

This report discusses several questions about voting-system security. To address these questions, this report begins with a description of the historical and policy context of the controversy. That is followed by an analysis of the issues in the broader context of computer security. The next section discusses several proposals that have been made for addressing those issues, and the last section discusses options for action that might be considered by policymakers.
Date: November 4, 2003
Creator: Fischer, Eric A.
Object Type: Report
System: The UNT Digital Library