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Measurements of Transverse Energy Distributions in Au+Au Collisions at {radical}s{sub NN} = 200 GeV

Description: Transverse energy (E{sub T}) distributions have been measured for Au+Au collisions at {radical}s{sub NN} = 200 GeV by the STAR collaboration at RHIC. E{sub T} is constructed from its hadronic and electromagnetic components, which have been measured separately. E{sub T} production for the most central collisions is well described by several theoretical models whose common feature is large energy density achieved early in the fireball evolution. The magnitude and centrality dependence of E{sub T} per charged particle agrees well with measurements at lower collision energy, indicating that the growth in E{sub T} for larger collision energy results from the growth in particle production. The electromagnetic fraction of the total E{sub T} is consistent with a final state dominated by mesons and independent of centrality.
Date: July 2, 2004
Creator: Adams, J.; Aggarwal, M.M.; Ahammed, Z.; Amonett, J.; Anderson, B.D.; Arkhipkin, D. et al.
Partner: UNT Libraries Government Documents Department

Modeling of Diffusion of Plutonium in Other Metals and of Gaseous Species in Plutonium-Based Systems

Description: Establish standards for temperature conditions under which plutonium, uranium, or neptunium from nuclear wastes permeates steel, with which it is in contact, by diffusion processes. The primary focus is on plutonium because of the greater difficulties created by the peculiarities of face-centered-cubic-stabilized (delta) plutonium (the form used in the technology generating the waste).
Date: July 2, 2004
Creator: Cooper, Bernard R.; Fernando, Gayanath W.; Beiden, S.; Setty, A. & Sevilla, E.H.
Partner: UNT Libraries Government Documents Department

Continuous Material Balance Reconciliation for a Modern Plutonium Processing Facility

Description: This paper describes a safeguards approach that can be deployed at any modern plutonium processing facility to increase the level of safeguards assurance and significantly reduce the impact of safeguards on process operations. One of the most perplexing problems facing the designers of plutonium processing facilities is the constraint placed upon the limit of error of the inventory difference (LEID). The current DOE manual constrains the LEID for Category I and II material balance areas to 2 per cent of active inventory up to a Category II quantity of the material being processed. For 239Pu a Category II quantity is two kilograms. Due to the large material throughput anticipated for some of the modern plutonium facilities, the required LEID cannot be achieved reliably during a nominal two month inventory period, even by using state-of-the-science non-destructive assay (NDA) methods. The most cost-effective and least disruptive solution appears to be increasing the frequency of material balance closure and thus reducing the throughput being measured during each inventory period. Current inventory accounting practices and systems can already provide the book inventory values at any point in time. However, closing the material balance with measured values has typically required the process to be cleaned out, and in-process materials packaged and measured. This process requires one to two weeks of facility down time every two months for each inventory, thus significantly reducing productivity. To provide a solution to this problem, a non-traditional approach is proposed that will include using in-line instruments to provide measurement of the process materials on a near real-time basis. A new software component will be developed that will operate with the standard LANMAS application to provide the running material balance reconciliation, including the calculation of the inventory difference and variance propagation. The combined measurement system and software implementation will make it ...
Date: July 2, 2004
Creator: CLARK, THOMAS G.
Partner: UNT Libraries Government Documents Department

TRANSPORT FROM OVERLAPPING ELECTRON AND ION DRIFTWAVE INSTABILITIES

Description: The electron temperature gradient (ETG) mode is a likely contributor to electron thermal transport in tokamaks. The ETG modes are dominantly unstable for poloidal wavelengths shorter than the ion gyroradius (high-k) where the ion response is adiabatic. Thus, they do not directly produce ion thermal or momentum transport or particle transport. Two potential mechanisms whereby ETG modes could produce transport in these channels are explored in this paper: a nonlinear coupling between high-k ETG modes and ions at low-k and a direct coupling when ETG modes and ion temperature gradient (ITG) modes are unstable in overlapping wavenumber ranges. It will be shown that the particle and momentum transport required to match experiment is small compared to the ETG driven electron thermal transport. Even quasilinearly ETG modes can produce ion transport if the ITG and ETG modes are both unstable at low-k. The implications of this for transport will be explored at the quasilinear level. A new gyro-Landau-fluid (GLF) closure model has been constructed in order to build a transport model which can include the coupling between electron and ion modes including trapped particles. The first growth rate spectra from this model will be shown to give an accurate approximation to the kinetic linear growth rates of drift-ballooning modes in tokamaks.
Date: July 2, 2004
Creator: STAEBLER,G.M; KINSEY,J.E & WALTZ,R.E
Partner: UNT Libraries Government Documents Department

Characterization of Supernate Samples from HLW Tanks 13H, 30H, 37H, 39H, 45F, 46F, and 49H

Description: This document presents work conducted in support of technical needs expressed, in part, by the Engineering, Procurement, and Construction Contractor for the Salt Waste Processing Facility (SWPF). The Department of Energy (DOE) requested that Savannah River National Laboratory (SRNL) analyze and characterize supernate waste from seven selected High Level Waste (HLW) tanks to allow classification of feed to be sent to the SWPF, verification that SWPF processes will be able to meet Saltstone Waste Acceptance Criteria (WAC), and updating of the Waste Characterization System (WCS) database. This document provides characterization data of samples obtained from Tanks 13H, 30H, 37H, 39H, 45F, 46F, and 49H and discusses results.Characterization of the waste tank samples involved several treatments and analysis at various stages of sample processing. These analytical stages included as-received liquid, post-dilution to 6.44 M sodium (target), post-acid digestion, post-filtration (at 3 filtration pore sizes), and after cesium removal using ammonium molybdophosphate (AMP). Results and observations obtained from testing include the following. All tanks will require cesium removal as well as treatment with Monosodium Titanate (MST) for 90Sr (Strontium) decontamination. A small filtration effect for 90Sr was observed for five of the seven tank wastes. No filtration effects were observed for Pu (Plutonium), Np (Neptunium), U (Uranium), or Tc (Technetium). 137Cs (Cesium) concentration is approximately E+09 pCi/mL for all the tank wastes. Tank 37H is significantly higher in 90Sr than the other six tanks. 237Np in the F-Area tanks(45F and 46F) are at least 1 order of magnitude less than the H-Area tank wastes. The data indicate a constant ratio of 99Tc to Cs in the seven tank wastes. This indicates the Tc remains largely soluble in Savannah River Site (SRS) waste and partition similarly with Cs. 241Am (Americium) concentration was low in the seven tank wastes. The majority of data were ...
Date: July 2, 2004
Creator: STALLINGS, MARY
Partner: UNT Libraries Government Documents Department

Social Security Administration: More Effort Needed to Assess Consistency of Disability Decisions

Description: A letter report issued by the Government Accountability Office with an abstract that begins "Each year, about 2.5 million people file claims with the Social Security Administration (SSA) for disability benefits. If the claim is denied at the initial level, the claimant may appeal to the hearings level. The hearings level has allowed more than half of all appealed claims, an allowance rate that has raised concerns about the consistency of decisions made at the two levels. To help ensure consistency, SSA began a "process unification" initiative in 1994 and recently announced a new proposal to strengthen its disability programs. This report examines (1) the status of SSA's process unification initiative, (2) SSA's assessments of possible inconsistencies in decisions between adjudication levels, and (3) whether SSA's new proposal incorporates changes to improve consistency in decisions between adjudication levels."
Date: July 2, 2004
Creator: United States. Government Accountability Office.
Partner: UNT Libraries Government Documents Department

Uranium Enrichment: Decontamination and Decommissioning Fund Is Insufficient to Cover Cleanup Costs

Description: A letter report issued by the Government Accountability Office with an abstract that begins "Decontaminating and decommissioning the nation's uranium enrichment plants, which are contaminated with hazardous materials, will cost billions of dollars and could span decades. In 1992, the Energy Policy Act created the Uranium Enrichment Decontamination and Decommissioning Fund (Fund) to pay for the plants' cleanup and to reimburse licensees of active uranium and thorium processing sites for part of their cleanup costs. This report discusses (1) what DOE has done to reduce the cleanup costs authorized by the Fund, and (2) the extent to which the Fund is sufficient to cover authorized activities."
Date: July 2, 2004
Creator: United States. Government Accountability Office.
Partner: UNT Libraries Government Documents Department

Drug Control: U.S. Nonmilitary Assistance to Colombia Is Beginning to Show Intended Results, but Programs Are Not Readily Sustainable

Description: A letter report issued by the Government Accountability Office with an abstract that begins "Since 2000, the U.S. government has provided a total of $3.3 billion to Colombia, making it the fifth largest recipient of U.S. assistance. Part of this funding has gone toward nonmilitary assistance to Colombia, including programs to (1) promote legitimate economic alternatives to coca and opium poppy; (2) assist Colombia's vulnerable groups, particularly internally displaced persons; and (3) strengthen the country's democratic, legal, and security institutional capabilities. GAO examined these programs' objectives, reported accomplishments, and identified the factors, if any, that limit project implementation and sustainability. We also examined the challenges faced by Colombia and the United States in continuing to support these programs."
Date: July 2, 2004
Creator: United States. Government Accountability Office.
Partner: UNT Libraries Government Documents Department

FAA Budget Policies and Practices

Description: Correspondence issued by the Government Accountability Office with an abstract that begins "In recent years, Congress has raised concerns about cost growth in the Federal Aviation Administration's (FAA) operating budget. Appropriators noted several expenses in FAA's fiscal year 2004 facilities and equipment (F&E) account budget submission that appeared to be ongoing operating expenses. The House and Senate appropriations subcommittee reports on FAA's fiscal year 2004 budget submission highlighted 17 such budget items and recommended that the expenses for these items either be transferred to the operations budget or not receive funding. As a result of these concerns, the Conference Report accompanying the fiscal year 2004 Omnibus Appropriations Act directed us to conduct an audit of FAA's policies and practices for determining whether an expense should be budgeted in its operating accounts or in the capital account. Specifically, this report addresses the following questions: (1) What are FAA's policies for determining whether an expense--including personnel compensation, benefits, travel, and related expenses--belongs in its capital (F&E) or Operations accounts? (2) How did FAA implement its policies for determining whether 17 specific budget line items identified by appropriators belong in its F&E or Operations accounts, including personnel compensation, benefits, travel, and related expenses? (3) How do FAA's budget policies compare with those of other civilian agencies with large acquisition budgets, such as the National Aeronautics and Space Administration (NASA) and the Department of Defense (DOD)?"
Date: July 2, 2004
Creator: United States. Government Accountability Office.
Partner: UNT Libraries Government Documents Department

Status of Key Recommendations GAO Has Made to DHS and Its Legacy Agencies

Description: Correspondence issued by the Government Accountability Office with an abstract that begins "Since the terrorist attacks of September 11, 2001, the federal government has undertaken numerous actions to enhance the nation's homeland security, including the creation of the Department of Homeland Security (DHS). One of the primary reasons for the establishment of DHS was to unify the vast national network of organizations and institutions involved in efforts to protect our nation. Since it began operations on March 1, 2003, DHS has faced enormous challenges to protect the nation from terrorism while it organizes itself into a coherent and integrated agency. We support Congress by reviewing various government programs and activities to help improve their performance and accountability. When our work identifies a significant need for action by the Congress or an agency, we develop recommended solutions. These recommendations identify actions we believe the department, agency, bureau, or office should implement to ensure government programs operate effectively and efficiently. This report responds to a Congressional request that we provide status information on key recommendations we have made to DHS and its legacy agencies. On June 30, 2004, we briefed Congress on the results of our review. This report transmits information provided during that briefing, including (1) the status of key GAO recommendations issued to DHS, (2) timeframes DHS established for implementing key recommendations, and (3) challenges DHS faces in implementing such recommendations."
Date: July 2, 2004
Creator: United States. Government Accountability Office.
Partner: UNT Libraries Government Documents Department

Wisconsin Emergency Management and Homeland Security Statutory Authorities Summarized

Description: This report is one of a series that profiles the emergency management and homeland security statutory authorities of the 50 states, the District of Columbia, the Commonwealth of the Northern Mariana Islands, the Commonwealth of Puerto Rico, and three territories (American Samoa, Guam, and the U.S. Virgin Islands). Each profile identifies the more significant elements of state statutes, generally as codified. This report focuses on the state of Wisconsin.
Date: July 2, 2004
Creator: Bea, Keith; Runyon, L. Cheryl & Warnock, Kae M.
Partner: UNT Libraries Government Documents Department

Rapid Qualitative Risk Assessment for Contaminant Leakage From Coal Seams During Underground Coal Gasification and CO2 Injection

Description: One of the major risks associated with underground coal gasification is contamination of local aquifers with a variety of toxic compounds. It is likely that the rate, volume, extent, and concentrations of contaminant plumes will depend on the local permeability field near the point of gasification. This field depends heavily on the geological history of stratigraphic deposition and the specifics of stratigraphic succession. Some coals are thick and isolated, whereas others are thinner and more regionally expressed. Some coals are overlain by impermeable units, such as marine or lacustrine shales, whereas others are overlain by permeable zones associated with deltaic or fluvial successions. Rapid stratigraphic characterization of the succession provides first order information as to the general risk of contaminant escape, which provides a means of ranking coal contaminant risks by their depositional context. This risk categorization could also be used for ranking the relative risk of CO{sub 2} escape from injected coal seams. Further work is needed to verify accuracy and provide some quantification of risks.
Date: July 2, 2004
Creator: Friedmann, S J
Partner: UNT Libraries Government Documents Department

A Method for Analysing High Resolution, Time Domain, Streak Camera Calibration Data

Description: Many experiments that require a highly accurate continuous time history of photon emission incorporate streak cameras into their setup. Nonlinear recordings both in time and spatial displacement are inherent to streak camera measurements. These nonlinearities can be attributed to sweep rate electronics, curvature of the electron optics, the magnification, and resolution of the electron optics. These nonlinearities are systematic; it has been shown that a short pulse laser source, an air-spaced etalon of known separation, and a defined spatial resolution mask can provide the proper image information to correct for the resulting distortion. A set of Interactive Data Language (IDL){sup 1} software routines were developed to take a series of calibration images showing temporally and spatially displaced points, and map these points from a nonlinear to a linear space-time resultant function. This correction function, in combination with standardized image correction techniques, can be applied to experiment data to minimize systematic errors and improve temporal and spatial resolution measurements.
Date: July 2, 2004
Creator: Silbernagel, C
Partner: UNT Libraries Government Documents Department

[Letter from Donnis Baggett to the TDNA Directors, July 2, 2004]

Description: Letter from Donnis Baggett to the TDNA Directors, on July 2, 2004 with the subject Board Appointments. The letter begins by stating that two directors serving on the TDNA board have resigned effective immediately. Larry Rose, president and publisher of the Corpus Christi Caller-Times is retiring, and Jack Pate, president and publisher of the San Angelo Standard-Times is moving to Indiana. Due to the significance of a full-staff, Baggett states that it is important to fill the two board positions immediately. As President of TDNA, Baggett has nominated two individuals to fill the board openings with the boards approval.
Date: July 2, 2004
Creator: Baggett, Donnis
Partner: UNT Libraries Special Collections

[Response form from Donnis Baggett, July 2, 2004]

Description: Response form from Donnis Baggett to the TDNA Directors in regard to two directors serving on the TDNA board having resigned. Due to the significance of a full-staff, Baggett states that it is important to fill the two board positions immediately. As President of TDNA, Baggett has nominated two individuals to fill the board openings with the boards approval and to respond with their decision.
Date: July 2, 2004
Creator: Baggett, Donnis
Partner: UNT Libraries Special Collections

235U and TRU Holdup Measurements on the 321-M Sawbenches

Description: The Analytical Development Section of Savannah River Technology Center (SRTC) was requested by the Facilities Disposition Projects (FDP) to determine the holdup of enriched uranium in the 321-M facility as part of an overall deactivation project of the facility. The 321-M facility was used to fabricate enriched uranium fuel assemblies, lithium-aluminum target tubes, neptunium assemblies, and miscellaneous components for the production reactors. The results of the holdup assays are essential for determining compliance with the Waste Acceptance Criteria, Material Control & Accountability, and to meet criticality safety controls. This report covers holdup measurements on two sawbench components that were used for cutting U-Al fuel rods. The benches contained U-Al residue scattered on the bench tops and bagged up in plastic containers. It was very important to obtain an estimate of the HEU content of this residue in order to remove criticality concerns before vacuuming it into a much smaller volume. A portable high purity germanium (HPGe) detection system and a portable sodium iodide (NaI) detection system were used to determine highly enriched uranium (HEU) holdup and to determine holdup Np-237 and Am-241 that were observed in these components. The measured Np-237 and Am-241 contents were especially important in these components because their presence is unusual and unexpected in 321-M. It was important to obtain a measured value of these two components to disposition the saw benches and to determine whether a separate waste stream was necessary for release of these contaminated components to the E-Area Solid Waste Vault. The reported values for Np-237 are < 0.8 mg on each of the two bench tops and < 3 {micro}g in the bag of chips. The reported values for Am-241 are < 500 ng on the two bench tops and < 15 ng in the bag of chips. Our results demonstrate an ...
Date: July 2, 2004
Creator: Dewberry, R
Partner: UNT Libraries Government Documents Department

Potential energy sputtering of EUVL materials

Description: Of the many candidates employed for understanding the erosion of critical Extreme Ultraviolet Lithography (EUVL) components, potential energy damage remains relatively uninvestigated. Unlike the familiar kinetic energy sputtering, which is a consequence of the momentum transferred by an ion to atoms in the target, potential energy sputtering occurs when an ion rapidly collects charge from the target as it neutralizes. Since the neutralization energy of a singly charged ion is typically on the order of 10 eV, potential energy effects are generally neglected for low charge state ions, and hence the bulk of the sputtering literature. As an ion's charge state is increased, the potential energy (PE) increases rapidly, e.g. PE(Xe{sup 1+})= 11 eV, PE(Xe{sup 10+}) = 810 eV, PE(Xe{sup 20+}) = 4.6 keV, etc. By comparison, the binding energy of a single atom on a surface is typically about 5 eV, so even relatively inefficient energy transfer mechanisms can lead to large quantities of material being removed, e.g. 25% efficiency for Xe{sup 10+} corresponds to {approx} 40 atoms/ion. By comparison, singly charged xenon ions with {approx} 20 keV of kinetic energy sputter only about 5 atoms/ion at normal incidence, and less than 1 atom/ion at typical EUV source energies. EUV light sources are optimized for producing approximately 10{sup 16} xenon ions per shot with an average charge state of q=10 in the core plasma. At operational rates of {approx}10 kHz, the number of ions produced per second becomes a whopping 10{sup 20}. Even if only one in a billion ions reaches the collector, erosion rates could reach {approx}10{sup 12} atoms per second, severely reducing the collector lifetime (for an average yield of 10 atoms/ion). In addition, efforts to reduce contamination effects may contribute to reduced neutralization and even larger potential energy damages rates (discussed further below). In order to ...
Date: July 2, 2004
Creator: Pomeroy, J. M.; Ratliff, L. P.; Gillaspy, J. D. & Bajt, S.
Partner: UNT Libraries Government Documents Department