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B physics: measurement of partial widths and search for direct cp violation in d0 meson decays (open access)

B physics: measurement of partial widths and search for direct cp violation in d0 meson decays

We present a measurement of relative partial widths and decay rate CP asymmetries in K{sup -}K{sup +} and {pi}{sup -}{pi}{sup +} decays of D{sup 0} mesons produced in p{bar p} collisions at {radical}s = 1.96TeV. We use a sample of 2 x 10{sup 5} D*{sup +} {yields} D{sup 0}{pi}{sup +} (and charge conjugate) decays with the D{sup 0} decaying to K{sup -}{pi}{sup +}, K{sup -}K{sup +}, and {pi}{sup -}{pi}{sup +}, corresponding to 123 pb{sup -1} of data collected by the Collider Detector at Fermilab II experiment at the Fermilab Tevatron collider. No significant direct CP violation is observed. We measure {Lambda}(D{sup 0} {yields} K{sup -}K{sup +})/{Lambda}(D{sup 0} {yields} K{sup -}{pi}{sup +}) = 0.0992 {+-} 0.0011 {+-} 0.0012, {Lambda}(D{sup 0} {yields} {pi}{sup -}{pi}{sup +})/{Lambda}(D{sup 0} {yields} K{sup -}{pi}{sup +}) = 0.03594 {+-} 0.00054 {+-} 0.00040, A{sub CP} (K{sup -}K{sup +}) = (2.0 {+-} 1.2 {+-} 0.6)%, and A{sub CP} ({pi}{sup -}{pi}{sup +}) = (1.0 {+-} 1.3 {+-} 0.6) %, where, in all cases, the first uncertainty is statistical and the second is systematic.
Date: April 4, 2005
Creator: Acosta, D.
System: The UNT Digital Library
Computation Directorate and Science& Technology Review Computational Science and Research Featured in 2002 (open access)

Computation Directorate and Science& Technology Review Computational Science and Research Featured in 2002

Thank you for your interest in the activities of the Lawrence Livermore National Laboratory Computation Directorate. This collection of articles from the Laboratory's Science & Technology Review highlights the most significant computational projects, achievements, and contributions during 2002. In 2002, LLNL marked the 50th anniversary of its founding. Scientific advancement in support of our national security mission has always been the core of the Laboratory. So that researchers could better under and predict complex physical phenomena, the Laboratory has pushed the limits of the largest, fastest, most powerful computers in the world. In the late 1950's, Edward Teller--one of the LLNL founders--proposed that the Laboratory commission a Livermore Advanced Research Computer (LARC) built to Livermore's specifications. He tells the story of being in Washington, DC, when John Von Neumann asked to talk about the LARC. He thought Teller wanted too much memory in the machine. (The specifications called for 20-30,000 words.) Teller was too smart to argue with him. Later Teller invited Von Neumann to the Laboratory and showed him one of the design codes being prepared for the LARC. He asked Von Neumann for suggestions on fitting the code into 10,000 words of memory, and flattered him about ''Labbies'' …
Date: April 4, 2003
Creator: Alchorn, A L
System: The UNT Digital Library
Assessing the Effects of Radiation Damage on Ni-base Alloys for the Prometheus Space Reactor System (open access)

Assessing the Effects of Radiation Damage on Ni-base Alloys for the Prometheus Space Reactor System

Ni-base alloys were considered for the Prometheus space reactor pressure vessel with operational parameters of {approx}900 K for 15 years and fluences up to 160 x 10{sup 20} n/cm{sup 2} (E > 0.1 MeV). This paper reviews the effects of irradiation on the behavior of Ni-base alloys and shows that radiation-induced swelling and creep are minor considerations compared to significant embrittlement with neutron exposure. While the mechanism responsible for radiation-induced embrittlement is not fully understood, it is likely a combination of helium embrittlement and solute segregation that can be highly dependent on the alloy composition and exposure conditions. Transmutation calculations show that detrimental helium levels would be expected at the end of life for the inner safety rod vessel (thimble) and possibly the outer pressure vessel, primarily from high energy (E > 1 MeV) n,{alpha} reactions with {sup 58}Ni. Helium from {sup 10}B is significant only for the outer vessel due to the proximity of the outer vessel to the BeO control elements. Recommendations for further assessments of the material behavior and methods to minimize the effects of radiation damage through alloy design are provided.
Date: April 4, 2006
Creator: Angeliu, T.; Ward, J. & Witter, J.
System: The UNT Digital Library
Improving Ventilation and Saving Energy: Final Report on Indoor Environmental Quality and Energy Monitoring in Sixteen Relocatable Classrooms (open access)

Improving Ventilation and Saving Energy: Final Report on Indoor Environmental Quality and Energy Monitoring in Sixteen Relocatable Classrooms

An improved HVAC system for portable classrooms was specified to address key problems in existing units. These included low energy efficiency, poor control of and provision for adequate ventilation, and excessive acoustic noise. Working with industry, a prototype improved heat pump air conditioner was developed to meet the specification. A one-year measurement-intensive field-test of ten of these IHPAC systems was conducted in occupied classrooms in two distinct California climates. These measurements are compared to those made in parallel in side by side portable classrooms equipped with standard 10 SEER heat pump air conditioner equipment. The IHPAC units were found to work as designed, providing predicted annual energy efficiency improvements of about 36 percent to 42 percent across California's climate zones, relative to 10 SEER units. Classroom ventilation was vastly improved as evidenced by far lower indoor minus outdoor CO2 concentrations. TheIHPAC units were found to provide ventilation that meets both California State energy and occupational codes and the ASHRAE minimum ventilation requirements; the classrooms equipped with the 10 SEER equipment universally did not meet these targets. The IHPAC system provided a major improvement in indoor acoustic conditions. HVAC system generated background noise was reduced in fan-only and fan and compressor …
Date: April 4, 2008
Creator: Apte, Michael G.; Norman, Bourassa; Faulkner, David; Hodgson, Alfred T.; Hotchi, Toshfumi; Spears, Michael et al.
System: The UNT Digital Library
Genetic and Molecular Dissection of Arsenic Hyperaccumulation in the fern Pteris vittata. (open access)

Genetic and Molecular Dissection of Arsenic Hyperaccumulation in the fern Pteris vittata.

Pteris vittata is a fern that is extraordinary in its ability to tolerate hyperaccumulate high levels of arsenic (As). The goals of the proposed research, to identify the genes that are necessary for As hyperaccumulation in P. vittata using molecular and genetic approaches and to understand the physiology of arsenic uptake and distribution in the living plant, were accomplished during the funding period. The genes that have been identified may ultimately enable the engineering or selection of other plants capable of As hyperaccumulation. This is important for the phytoremediation of arsenic-contaminated soils in areas where P. vittata cannot grow.
Date: April 4, 2008
Creator: Banks, Jo Ann & Salt, David
System: The UNT Digital Library
Highly Enriched Uranium Transparency Program (open access)

Highly Enriched Uranium Transparency Program

None
Date: April 4, 2006
Creator: Benton, J B; Leich, D A & DiSabatino, Jr., A A
System: The UNT Digital Library
On the Transition from Thermally-driven to Ponderomotively-driven Stimulated Brillouin Scattering and Filamentation of Light in Plasma (open access)

On the Transition from Thermally-driven to Ponderomotively-driven Stimulated Brillouin Scattering and Filamentation of Light in Plasma

The dispersion properties of ion acoustic waves and their nonlinear coupling to light waves through ponderomotive and thermal forces are sensitive to the strength of electron-ion collisions. Here, we consider the growth rate of stimulated Brillouin scattering (SBS) when the driven acoustic wave frequency and wavelength span the range of small to large compared to electron-ion collision frequency and mean free path respectively. We find in all cases the thermal contributions to the SBS growth rate are insignificant if the ion acoustic wave frequency is greater than the electron-ion collision frequency and the wavelength is much shorter than the electron-ion mean free path. On the other hand, the purely growing filamentation instability remains thermally driven for shorter wavelengths than SBS even when the growth rate is larger than the acoustic frequency.
Date: April 4, 2005
Creator: Berger, R. L.; Valeo, E. J. & Brunner, S.
System: The UNT Digital Library
Preparation of Phased and Merged Safety Analysis Reports for New DOE Nuclear Facilities (open access)

Preparation of Phased and Merged Safety Analysis Reports for New DOE Nuclear Facilities

The Spent Nuclear Fuels Project (SNFP) is charged with moving to storage 2,100 metric tons of spent nuclear fuel elements left over from plutonium production at DOE'S Hanford site in Washington state. Two new facilities, the Cold Vacuum Drying Facility (CVDF) and the Canister Storage Building (CSB) are in final construction. In order to meet aggressive schedule commitments, the SNFP chose to prepare the safety analysis reports (SAR's) in phases that covered only specific portions of each facility's design as it was built. Each SAR also merged the preliminary and final safety analysis reports into a single SAR, thereby covering all aspects of design, construction, and operation for that portion (phase) of the facility. A policy of ''NRC equivalency'' was also implemented in parallel with this effort, with the goal of achieving a rigor of safety analysis equivalent to that of NRC-licensed fuel processing facilities. DOE Order 5480.23. ''Nuclear Safety Analysis Reports'' allows preparation of both a phased and a merged SAR to accelerate construction schedules. However, project managers must be aware that such acceleration is not guaranteed. Managers considering this approach for their project should be cognizant of numerous obstacles that will be encountered. Merging and phasing SAR's will …
Date: April 4, 2000
Creator: Bishop, G. E.
System: The UNT Digital Library
Iraq: Regional Perspectives and U.S. Policy (open access)

Iraq: Regional Perspectives and U.S. Policy

This report provides information about the current perspectives and policies of Iraq's neighbors; analyzes potential regional responses to continued insurgency, sectarian and ethnic violence, and long-term stabilization; discusses shared concerns and U.S. long-term regional interests; and reviews U.S. policy options for responding to various contingencies.
Date: April 4, 2008
Creator: Blanchard, Christopher M.; Katzman, Kenneth; Migdalovitz, Carol; Prados, Alfred & Sharp, Jeremy
System: The UNT Digital Library
Smoke Dispersion Simulations for Prescribed Burns at Site 300, Lawrence Livermore National Laboratory (open access)

Smoke Dispersion Simulations for Prescribed Burns at Site 300, Lawrence Livermore National Laboratory

Each year, as part of its ongoing commitment to safe operating practices Lawrence Livermore National Laboratory (LLNL) conducts prescribed burns at its Site 300 complex. LLNL consistently adheres to stringent, self-imposed safety standards in all of its activities, and the annual prescribed burning at Site 300 is done to prevent an accumulation of vegetative fuels (primarily grasses) that could cause an unacceptable risk of wildfire ignition. The LLNL prescribed burn procedure (Burklin, 2001) calls for the sequential, controlled burning individual small land plots by the LLNL Fire Department. Essentially the same burning procedure is repeated on a yearly basis. The burns usually are conducted in May and June; however, on rare occasions the burning has been done as late in the year as July. To the best of our knowledge there has never been an environmental problem caused by the smoke from these prescribed burns. Indeed, the avoidance of undesirable environmental impacts is inherent in the very concept of prescription burning. In order to better understand, in a quantitative sense, the atmospheric dispersion of smoke from prescribed burns at Site 300, and to examine how smoke behavior might differ for different burn months and burn-plot terrain, the National Atmospheric Release …
Date: April 4, 2002
Creator: Bradley, M M; Aluzzi, F J; Vogt, P J; Hall, C H; Neher, L A & Wilder, L A
System: The UNT Digital Library
Doublets and Other Allied Well Patterns (open access)

Doublets and Other Allied Well Patterns

This report looks at a host of balanced patterns at unity mobility ratio. The geometries and rates ranged broadly. It was found that whenever total production and injection are equal, we can gain considerable insight on the flow equations and the fluid movement. The balanced patterns, where the wells are arrayed around a single injector or a single producer, we found that simple equations can define the nature of steady state flow lines and geometries of the flow paths, and their breakthrough behavior. When the rates are not equal, but still are balanced, the geometries are more complex, but still amenable to analytic solution.
Date: April 4, 2001
Creator: Brigham, William E.
System: The UNT Digital Library
Export Tax Benefits and the WTO: The Extraterritorial Income Exclusion and Foreign Sales Corporations (open access)

Export Tax Benefits and the WTO: The Extraterritorial Income Exclusion and Foreign Sales Corporations

None
Date: April 4, 2005
Creator: Brumbaugh, David L.
System: The UNT Digital Library
Major Tax Issues in the 108th Congress (open access)

Major Tax Issues in the 108th Congress

None
Date: April 4, 2003
Creator: Brumbaugh, David L. & Richards, Don C.
System: The UNT Digital Library
Army Transformation and Modernization: Overview and Issues for Congress (open access)

Army Transformation and Modernization: Overview and Issues for Congress

The U.S. Army has begun an ambitious program intended to transform itself into a strategically responsive force dominant in all types of ground operations. As planned, its Objective Force will eventually meld all ongoing initiatives into a force based on a high-tech Future Combat System. This short report briefly describes the program and discusses issues of feasibility, viability, and affordability of potential interest to Congress.
Date: April 4, 2001
Creator: Bruner, Edward F.
System: The UNT Digital Library
Fishery, Aquaculture, and Marine Mammal Legislation in the 107th Congress (open access)

Fishery, Aquaculture, and Marine Mammal Legislation in the 107th Congress

This report presents the information related to the fishery, aquaculture, and marine mammal legislation enacted by the 107th congress
Date: April 4, 2002
Creator: Buck, Eugene H.
System: The UNT Digital Library
Fishery, Aquaculture, and Marine Mammal Legislation in the 109th Congress (open access)

Fishery, Aquaculture, and Marine Mammal Legislation in the 109th Congress

Fish and marine mammals are important resources in open ocean and nearshore coastal areas; many federal laws and regulations guide their management. This report discusses a variety of laws and legislation pertaining to this issue.
Date: April 4, 2006
Creator: Buck, Eugene H.
System: The UNT Digital Library
Integrated Safety Management System Phase 1 and 2 Verification for the Environmental Restoration Contractor Volumes 1 and 2 (open access)

Integrated Safety Management System Phase 1 and 2 Verification for the Environmental Restoration Contractor Volumes 1 and 2

DOE Policy 450.4 mandates that safety be integrated into all aspects of the management and operations of its facilities. The goal of an institutionalized Integrated Safety Management System (ISMS) is to have a single integrated system that includes Environment, Safety, and Health requirements in the work planning and execution processes to ensure the protection of the worker, public, environment, and the federal property over the life cycle of the Environmental Restoration (ER) Project. The purpose of this Environmental Restoration Contractor (ERC) ISMS Phase MI Verification was to determine whether ISMS programs and processes were institutionalized within the ER Project, whether these programs and processes were implemented, and whether the system had promoted the development of a safety conscious work culture.
Date: April 4, 2000
Creator: CARTER, R.P.
System: The UNT Digital Library
Cleanup Verification Package for the 116-K-2 Effluent Trench (open access)

Cleanup Verification Package for the 116-K-2 Effluent Trench

This cleanup verification package documents completion of remedial action for the 116-K-2 effluent trench, also referred to as the 116-K-2 mile-long trench and the 116-K-2 site. During its period of operation, the 116-K-2 site was used to dispose of cooling water effluent from the 105-KE and 105-KW Reactors by percolation into the soil. This site also received mixed liquid wastes from the 105-KW and 105-KE fuel storage basins, reactor floor drains, and miscellaneous decontamination activities.
Date: April 4, 2006
Creator: Capron, J. M.
System: The UNT Digital Library
Statistical evaluation of effluent monitoring data for the 200 Area Treated Effluent Disposal Facility (open access)

Statistical evaluation of effluent monitoring data for the 200 Area Treated Effluent Disposal Facility

The 200 Area Treated Effluent Disposal Facility (TEDF) consists of a pair of infiltration basins that receive wastewater originating from the 200 West and 200 East Areas of the Hanford Site. TEDF has been in operation since 1995 and is regulated by State Waste Discharge Permit ST 4502 (Ecology 1995) under the authority of Chapter 90.48 Revised Code of Washington (RCW) and Washington Administrative Code (WAC) Chapter 173-216. The permit stipulates monitoring requirements for effluent (or end-of-pipe) discharges and groundwater monitoring for TEDF. Groundwater monitoring began in 1992 prior to TEDF construction. Routine effluent monitoring in accordance with the permit requirements began in late April 1995 when the facility began operations. The State Waste Discharge Permit ST 4502 included a special permit condition (S.6). This condition specified a statistical study of the variability of permitted constituents in the effluent from TEDF during its first year of operation. The study was designed to (1) demonstrate compliance with the waste discharge permit; (2) determine the variability of all constituents in the effluent that have enforcement limits, early warning values, and monitoring requirements (WHC 1995); and (3) determine if concentrations of permitted constituents vary with season. Additional and more frequent sampling was conducted …
Date: April 4, 2000
Creator: Chou, C. J. & Johnson, V. G.
System: The UNT Digital Library
IR Properties of Ge-Doped CH - A Continuation (open access)

IR Properties of Ge-Doped CH - A Continuation

We have reexamined Ge-doped CH and have found that the material is more reactive to air than previously understood. The Ge-doped material as formed shows by IR the presence of a Ge-H linkage that oxidizes rapidly, giving rise to a significant OH absorption. This broad peak impacts IR layering wavelengths of interest.
Date: April 4, 2003
Creator: Cook, Bob; Nikroo, Abbas & Czechowicz, Don
System: The UNT Digital Library
China's Impact on the U.S. Automotive Industry (open access)

China's Impact on the U.S. Automotive Industry

This report discusses China’s impact on the U.S. Automotive Industry. Congress has been concerned with broad policies giving Chinese exporters unfair trade advantages. The Senate approved a bill, added as an amendment to other legislation that would place a high tariff on Chinese imports unless China revalues its pegged exchange rate (S. 295). Further action has been postponed on this measure. Legislation to allow U.S. producers to bring countervailing duty cases against Chinese firms subsidized by their government has been approved in the House (H.R. 3283), and a new law has tightened rules against trade in counterfeited goods (P.L. 109-181).
Date: April 4, 2006
Creator: Cooney, Stephen
System: The UNT Digital Library
AIDS in Africa (open access)

AIDS in Africa

Sub-Saharan Africa has been far more severely affected by AIDS than any other part of the world. The United Nations reports that 29.4 million adults and children are infected with the HIV virus in the region, which has about 10% of the world's population but more than 70% of the worldwide total of infected people. This report discusses this issue in detail, including the cause of the African AIDS epidemic, the social and economic consequences, response and treatment, and U.S. policy.
Date: April 4, 2003
Creator: Copson, Raymond W.
System: The UNT Digital Library
Kenya: The December 2007 Elections and the Challenges Ahead (open access)

Kenya: The December 2007 Elections and the Challenges Ahead

This report discusses an overview of the December 2007 elections and the challenges of Kenya.
Date: April 4, 2008
Creator: Dagne, Ted
System: The UNT Digital Library
House Committee Hearings: The ”Minority Witness Rule” (open access)

House Committee Hearings: The ”Minority Witness Rule”

This report provides an overview of the House Committee hearings, including the origin of the minority witness rule and the majority prerogatives and minority witnesses.
Date: April 4, 2007
Creator: Davis, Christopher M.
System: The UNT Digital Library