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Office of Inspector General audit report on credit card usage at the Ohio Field Office and the Fernald and Miamisburg Environmental Management Projects

Description: In 1994 the Department of Energy (Department) obtained the services of Rocky Mountain BankCard System, through the use of a General Services Administration contract, as a means for the Department and its contractors to make small purchases. The use of credit cards was expected to simplify small purchase procedures and improve cash management. The Ohio Field Office (Field Office) uses the credit card system and oversees usage by its area offices. Contractors under the Field Office also use the credit card system to make small purchases. The Office of Inspector General (OIG) has issued one audit report concerning the use of credit cards. In April 1996, the OIG issued Report WR-B-96-06, Audit of Bonneville Power Administration`s Management of Information Resources. The audit concluded that improvements could be made in implementing credit card and property procedures in Bonneville`s management of computer-related equipment. Specifically, many credit card purchases were made by employees whose authority to buy was not properly documented, and the purchasing files often lacked invoices that would show what was purchased. Additionally, some cardholders split purchases to avoid credit card limits. The objective of this audit was to determine whether the Field Office, Fernald and Miamisburg Environmental Management Projects, Fluor Daniel, and B and W were using credit cards for the appropriate purposes and within the limitations established by Federal and Departmental regulations.
Date: March 1, 1999
Partner: UNT Libraries Government Documents Department

Renewable Energy Deployment in the Federal Sector

Description: To reduce energy costs and help protect the environment, the U.S. Department of Energy's (DOE's) Federal Energy Management Program (FEMP) assists Federal agencies in becoming more energy efficient and using more renewable energy. FEMP's renewable energy program has identified three technology pathways to this goal: (1) purchasing and installing cost-effective renewable energy technologies at Federal sites; (2) purchasing a portion of Federal facilities' electricity from renewable power sources; and (3) incorporating the principles of low-energy design in new construction. To support these pathways, FEMP has also identified three overarching actions that need to be taken: (1) partnering with others to develop clear messages about renewable energy that resonate with the public; (2) coordinating agency programs to leverage resources and emphasize renewables; and (3) securing commitments and support from Federal leadership. This paper describes FEMP's progress in each pathway and supporting action and includes examples of recent Federal projects.
Date: March 24, 1999
Creator: Carlisle, N.; Eiffert, P. (National Renewable Energy Laboratory) & Crawley, A. S. (U.S. Department of Energy, Office of Energy Efficiency and Renewable Energy)
Partner: UNT Libraries Government Documents Department

ANL calculational methodologies for determining spent nuclear fuel source term

Description: Over the last decade Argonne National Laboratory has developed reactor depletion methods and models to determine radionuclide inventories of irradiated EBR-II fuels. Predicted masses based on these calculational methodologies have been validated using available data from destructive measurements--first from measurements of lead EBR-II experimental test assemblies and later using data obtained from processing irradiated EBR-II fuel assemblies in the Fuel Conditioning Facility. Details of these generic methodologies are described herein. Validation results demonstrate these methods meet the FCF operations and material control and accountancy requirements.
Date: March 24, 2000
Creator: McKnight, R. D.
Partner: UNT Libraries Government Documents Department

UTILITY ADVANCED TURBINE SYSTEMS (ATS) TECHNOLOGY READINESS TESTING PHASE 3 RESTRUCTURED (3R)

Description: In the early 90's GE recognized the need to introduce new technology to follow on to the ''F'' technology the Company introduced in 1988. By working with industry and DOE, GE helped shape the ATS program goal of demonstrating a gas turbine, combined-cycle system using natural gas as the primary fuel that achieves the following targets: system efficiency exceeding 60% lower heating value basis; environmental superiority under full-load operating conditions without the use of post-combustion emissions controls, environmental superiority includes limiting NO{sub 2} to less than 10 parts per mission by volume (dry basis) at 15% oxygen; busbar energy costs that are 10% less than current state-of-the-art turbine systems meeting the same environmental requirements; fuel-flexible designs operating on natural gas but also capable of being adapted to operate on coal-based, distillate, or biomass fuels; reliability-availability-maintainability (RAM) that is equivalent to modern advanced power generation systems; and commercial systems that could enter the market in the year 2000.
Date: March 30, 1999
Partner: UNT Libraries Government Documents Department

Demand Activated Manufacturing Architecture (DAMA) model for supply chain collaboration

Description: The Demand Activated Manufacturing Architecture (DAMA) project during the last five years of work with the U.S. Integrated Textile Complex (retail, apparel, textile, and fiber sectors) has developed an inter-enterprise architecture and collaborative model for supply chains. This model will enable improved collaborative business across any supply chain. The DAMA Model for Supply Chain Collaboration is a high-level model for collaboration to achieve Demand Activated Manufacturing. The five major elements of the architecture to support collaboration are (1) activity or process, (2) information, (3) application, (4) data, and (5) infrastructure. These five elements are tied to the application of the DAMA architecture to three phases of collaboration - prepare, pilot, and scale. There are six collaborative activities that may be employed in this model: (1) Develop Business Planning Agreements, (2) Define Products, (3) Forecast and Plan Capacity Commitments, (4) Schedule Product and Product Delivery, (5) Expedite Production and Delivery Exceptions, and (6) Populate Supply Chain Utility. The Supply Chain Utility is a set of applications implemented to support collaborative product definition, forecast visibility, planning, scheduling, and execution. The DAMA architecture and model will be presented along with the process for implementing this DAMA model.
Date: March 13, 2000
Creator: CHAPMAN,LEON D. & PETERSEN,MARJORIE B.
Partner: UNT Libraries Government Documents Department

Validation results based on the spent fuel demonstration program at FCF

Description: Over the last decade Argonne National Laboratory has developed reactor depletion methods and models to determine radionuclide inventories of irradiated EBR-II fuels. A brief description of these burnup methodologies is presented herein. Predicted masses for the irradiated Zirconium-alloy driver fuel based on these calculational methodologies have been validated using available data from destructive measurements--first from measurements of lead EBR-II experimental test assemblies and later using data obtained from processing irradiated EBR-II fuel assemblies in the Fuel Conditioning Facility. The results of Analytical Laboratory measurements obtained for EBR-II driver fuel samples obtained over the duration of the Spent Fuel Demonstration Program are compared with calculated values. These validation results demonstrate these methods meet the FCF operations and material control and accountancy requirements.
Date: March 24, 2000
Creator: McKnight, R. D. & Krsul, J. R.
Partner: UNT Libraries Government Documents Department

New Brunswick Laboratory progress report, October 1994--September 1995

Description: The mission of the New Brunswick Laboratory (NBL) of the A. S. Department of Energy (DOE) is to serve as the National Certifying Authority for nuclear reference materials and to provide an independent Federal technical staff and laboratory resource performing nuclear material measurement, safeguards, and non-proliferation functions in support of multiple program sponsors. This annual report describes accomplishments achieved in carrying out NBL`s assigned missions.
Date: March 1, 1996
Partner: UNT Libraries Government Documents Department

Procuring Low-Energy Design and Consulting Services

Description: Dozens of Federal agencies design, construct, renovate, and maintain thousands of offices, warehouses, and dwelling units in a wide range of climates and conditions. As the world's largest consumer of energy (1.2 quadrillion British thermal units [Btu] delivered to the point of use in fiscal year 1994), the Federal government has a tremendous opportunity to save vast amounts of money each year in energy costs. Executive Order 12902, which was passed in 1994, challenges Federal building managers to reduce the energy consumption of these facilities (30% from 1985 levels by the year 2005). To meet this challenge, they have been directed to incorporate energy efficiency, renewable energy, and specifically, passive solar design into all major projects when it is technically and economically feasible. But how can they do it? The information presented here will help them initiate and manage the procurement and design process and answer many of their questions. This is a Guide for Federal Building Managers, Architects, and Engineers.
Date: March 2, 1999
Creator: Prowler, D.
Partner: UNT Libraries Government Documents Department

Energy Strategic Planning & Self-Sufficiency Project

Description: This report provides information regarding options available, their advantages and disadvantages, and the costs for pursuing activities to advance Smith River Rancheria toward an energy program that reduces their energy costs, allows greater self-sufficiency and stimulates economic development and employment opportunities within and around the reservation. The primary subjects addressed in this report are as follow: (1) Baseline Assessment of Current Energy Costs--An evaluation of the historical energy costs for Smith River was conducted to identify the costs for each component of their energy supply to better assess changes that can be considered for energy cost reductions. (2) Research Viable Energy Options--This includes a general description of many power generation technologies and identification of their relative costs, advantages and disadvantages. Through this research the generation technology options that are most suited for this application were identified. (3) Project Development Considerations--The basic steps and associated challenges of developing a generation project utilizing the selected technologies are identified and discussed. This included items like selling to third parties, wheeling, electrical interconnections, fuel supply, permitting, standby power, and transmission studies. (4) Energy Conservation--The myriad of federal, state and utility programs offered for low-income weatherization and utility bill payment assistance are identified, their qualification requirements discussed, and the subsequent benefits outlined. (5) Establishing an Energy Organization--The report includes a high level discussion of formation of a utility to serve the Tribal membership. The value or advantages of such action is discussed along with some of the challenges. (6) Training--Training opportunities available to the Tribal membership are identified.
Date: March 30, 2005
Creator: Retzlaff, Greg
Partner: UNT Libraries Government Documents Department

Energy Strategic Planning & Sufficiency Project

Description: This report provides information regarding options available, their advantages and disadvantages, and the costs for pursuing activities to advance Smith River Rancheria toward an energy program that reduces their energy costs, allows greater self-sufficiency and stimulates economic development and employment opportunities within and around the reservation. The primary subjects addressed in this report are as follows: (1) Baseline Assessment of Current Energy Costs--An evaluation of the historical energy costs for Smith River was conducted to identify the costs for each component of their energy supply to better assess changes that can be considered for energy cost reductions. (2) Research Viable Energy Options--This includes a general description of many power generation technologies and identification of their relative costs, advantages and disadvantages. Through this research the generation technology options that are most suited for this application were identified. (3) Project Development Considerations--The basic steps and associated challenges of developing a generation project utilizing the selected technologies are identified and discussed. This included items like selling to third parties, wheeling, electrical interconnections, fuel supply, permitting, standby power, and transmission studies. (4) Energy Conservation--The myriad of federal, state and utility programs offered for low-income weatherization and utility bill payment assistance are identified, their qualification requirements discussed, and the subsequent benefits outlined. (5) Establishing an Energy Organization--The report includes a high level discussion of formation of a utility to serve the Tribal membership. The value or advantages of such action is discussed along with some of the challenges. (6) Training--Training opportunities available to the Tribal membership are identified.
Date: March 30, 2005
Creator: Retziaff, Greg
Partner: UNT Libraries Government Documents Department

Industrial Membrane Filtration and Short-bed Fractal Separation Systems for Separating Monomers from Heterogeneous Plant Material

Description: Large-scale displacement of petroleum will come from low-cost cellulosic feedstocks such as straw and corn stover crop residues. This project has taken a step toward making this projection a reality by reducing capital and energy costs, the two largest cost factors associated with converting cellulosic biomass to chemicals and fuels. The technology exists for using acid or enzyme hydrolysis processes to convert biomass feedstock (i.e., waste cellulose such as straw, corn stover, and wood) into their base monomeric sugar building blocks, which can, in turn, be processed into chemicals and fuels using a number of innovative fermentation technologies. However, while these processes are technically possible, practical and economic barriers make these processes only marginally feasible or not feasible at all. These barriers are due in part to the complexity and large fixed and recurring capital costs of unit operations including filtration, chromatographic separation, and ion exchange. This project was designed to help remove these barriers by developing and implementing new purification and separation technologies that will reduce the capital costs of the purification and chromatographic separation units by 50% to 70%. The technologies fundamental to these improvements are: (a) highly efficient clarification and purification systems that use screening and membrane filtration to eliminate suspended solids and colloidal material from feed streams and (b) fractal technology based chromatographic separation and ion exchange systems that can substitute for conventional systems but at much smaller size and cost. A non-hazardous ''raw sugar beet juice'' stream (75 to 100 gal/min) was used for prototype testing of these technologies. This raw beet juice stream from the Amalgamated Sugar LLC plant in Twin Falls, Idaho contained abrasive materials and membrane foulants. Its characteristics were representative of an industrial-scale heterogeneous plant extract/hydrolysis stream, and therefore was an ideal model system for developing new separation equipment. Subsequent testing ...
Date: March 31, 2005
Creator: Kearney, M; Kochergin, V; Hess, R; Foust, T; Herbst, R & Mann, N
Partner: UNT Libraries Government Documents Department

An engineering-economic analysis of combined heat and power technologies in a (mu)grid application

Description: This report describes an investigation at Ernesto Orlando Lawrence Berkeley National Laboratory (Berkeley Lab) of the potential for coupling combined heat and power (CHP) with on-site electricity generation to provide power and heating, and cooling services to customers. This research into distributed energy resources (DER) builds on the concept of the microgrid (mGrid), a semiautonomous grouping of power-generating sources that are placed and operated by and for the benefit of its members. For this investigation, a hypothetical small shopping mall (''Microgrid Oaks'') was developed and analyzed for the cost effectiveness of installing CHP to provide the mGrid's energy needs. A mGrid consists of groups of customers pooling energy loads and installing a combination of generation resources that meets the particular mGrid's goals. This study assumes the mGrid is seeking to minimize energy costs. mGrids could operate independently of the macrogrid (the wider power network), but they are usually assumed to be connected, through power electronics, to the macrogrid. The mGrid in this study is assumed to be interconnected to the macrogrid, and can purchase some energy and ancillary services from utility providers.
Date: March 1, 2002
Creator: Bailey, Owen; Ouaglal, Boubekeur; Bartholomew, Emily; Marnay, Chris & Bourassa, Norman
Partner: UNT Libraries Government Documents Department

Dissection of Molecular Mechanisms Regulating Protein Body Formation in Maize Endosperm - DE-FG03-95-ER20183 B139

Description: Dissection of Molecular Mechanisms Regulating Protein Body Formation in Maize Endosperm - DE-FG03-95-ER20183 Final Technical Report and Patent Summary Dr. Brian A. Larkins, Department of Plant Sciences, University of Arizona, Tucson, AZ 85721 Endosperm texture is an important quality trait in maize, as it influences the shipping characteristics of the grain, its susceptibility to insects, the yield of grits from dry milling, energy costs during wet milling, and the baking and digestibility properties of the flour. There appears to be a causal relationship between kernel hardness and the formation of zein-containing protein bodies, as mutations affecting protein body number and structure are associated with a soft, starchy kernel. In this project we used a variety of approaches to better understand this relationship and investigate the molecular and biochemical changes associated with starchy endosperm mutants. We characterized the distribution of zein mRNAs on endosperm rough endoplasmic reticulum (RER) membranes and the interactions between zein proteins, as each of these could influence the structure of protein bodies. Based on in situ hybridization, mRNAs encoding the 22-kD alpha- and 27-kD gamma-zeins are randomly distributed on RER; hence, mRNA targeting does not appear to influence the formation of protein bodies. Investigation of the interactions between zein proteins (alpha, beta, gamma, delta) with the yeast two-hybrid system showed that interactions between the 19- and 22-alpha-zeins are relatively weak, although each of them interacted strongly with the 10-kD delta-zein. Strong interactions were detected between the alpha- and delta-zeins and the 16-kD gamma- and 15-kD beta-zeins; however, the 50-kD and 27-kD gamma-zeins did not interact detectably with the alpha- and delta-zein proteins. The NH2- and COOH-terminal domains of the 22-kD alpha-zein were found to interact most strongly with the 15-kD beta- and 16-kD gamma-zeins, suggesting the 16-kD and 15-kD proteins bind and assemble alpha-zeins in protein bodies. ...
Date: March 21, 2003
Creator: Larkins, Brian A.
Partner: UNT Libraries Government Documents Department

Web-based energy information systems for large commercial buildings

Description: Energy Information Systems (EIS), which monitor and organize building energy consumption and related trend data over the Internet, have been evolving over the past decade. This technology helps perform key energy management functions such as organizing energy use data, identifying energy consumption anomalies, managing energy costs, and automating demand response strategies. During recent years numerous developers and vendors of EIS have been deploying these products in a highly competitive market. EIS offer various software applications and services for a variety of purposes. Costs for such system vary greatly depending on the system's capabilities and how they are marketed. Some products are marketed directly to end users while others are made available as part of electric utility programs. EIS can be a useful tool in building commissioning and retro-commissioning. This paper reviews more than a dozen EIS. We have developed an analytical framework to characterize the main features of these products, which are developed for a variety of utility programs and end-use markets. The purpose of this research is to evaluate EIS capabilities and limitations, plus examine longer-term opportunities for utilizing such technology to improve building energy efficiency and load management.
Date: March 29, 2003
Creator: Motegi, Naoya & Piette, Mary Ann
Partner: UNT Libraries Government Documents Department

Nuclear materials inventory plan

Description: In any processing, manufacturing, or active storage facility it is impractical to assume that any physical security system can prevent the diversion of Special Nuclear Material (SNM). It is, therefore, the responsibility of any DOE Contractor, Licensee, or other holder of SNM to provide assurance that loss or diversion of a significant quantity of SNM is detectable. This ability to detect must be accomplishable within a reasonable time interval and can be accomplished only by taking physical inventories. The information gained and decisions resulting from these inventories can be no better than the SNM accounting system and the quality of measurements performed for each receipt, removal and inventory. Inventories interrupt processing or production operations, increase personnel exposures, and can add significantly to the cost of any operation. Therefore, realistic goals for the inventory must be defined and the relationship of the inherent parameters used in its validation be determined. Purpose of this document is to provide a statement of goals and a plan of action to achieve them.
Date: March 1, 1982
Creator: Doerr, R. W. & Nichols, D. H.
Partner: UNT Libraries Government Documents Department

RJESTATS: a system of programs for remote job entry station accounting

Description: The RJESTATS system of programs provides accounting information on the use of the Environmental Sciences Division Remote Job Entry (RJE) facility. Summaries can be generated to display the number and kind of users, types of jobs run through the RJE facility, and the persons (or projects) that are utilizing the facility. Sample tables are presented to show certain summaries by user name, job name initials, and types of jobs run. RJESTATS is useful for managing and determining the use of an IBM-compatible RJE facility.
Date: March 1, 1978
Creator: Strand, R. H.; Raine, G. B.; Tharp, M. L. & Griffith, N. A.
Partner: UNT Libraries Government Documents Department

Statistical near-real-time accountancy procedures applied to AGNS (Allied General Nuclear Services) minirun data using PROSA

Description: The computer program PROSA (PROgram for Statistical Analysis of near-real-time accountancy data) was developed as a tool to apply statistical test procedures to a sequence of materials balance results for detecting losses of material. First applications of PROSA to model facility data and real plant data showed that PROSA is also usable as a tool for process or measurement control. To deepen the experience for the application of PROSA to real data of bulk-handling facilities, we applied it to uranium data of the Allied General Nuclear Services miniruns, where accountancy data were collected on a near-real-time basis. Minirun 6 especially was considered, and the pulsed columns were chosen as materials balance area. The structure of the measurement models for flow sheet data and actual operation data are compared, and methods are studied to reduce the error for inventory measurements of the columns.
Date: March 1, 1988
Creator: Beedgen, R.
Partner: UNT Libraries Government Documents Department

Survey of simulation methods for modeling pulsed sieve-plate extraction columns

Description: The report first considers briefly the use of liquid-liquid extraction in nuclear fuel reprocessing and then describes the operation of the pulse column. Currently available simulation models of the column are reviewed, and followed by an analysis of the information presently available from which the necessary parameters can be obtained for use in a model of the column. Finally, overall conclusions are given regarding the information needed to develop an accurate model of the column for materials accountability in fuel reprocessing plants. 156 references.
Date: March 1, 1979
Creator: Burkhart, L.
Partner: UNT Libraries Government Documents Department

Process monitor design for an extraction column: an application of estimation/detection

Description: The NRC Safeguards Program at LLL is directed toward developing a methodology for assessing the effectiveness of material control and accounting systems at processing/reprocessing facilities for special nuclear material. The methodology under development requires many types of mathematical models including performance models of safeguard components. Included in the class of safeguard components are real-time measurement systems which incorporate on-line estimators/detectors for the timely detection of material losses. Performance modeling generally involves mathematical model development and simulation of the physical process being measured. This report discusses the development of material estimator designs for a liquid--liquid extraction column using a reprocessing application. These designs are applicable to any processing unit which can be adequately represented by linear or nonlinear models in state space form. Although this work is discussed in the context of a plutonium extraction column, it is representative of two classes of safeguard components which are generic to any fuel cycle involving chemical separations/purifications.
Date: March 1, 1979
Creator: Candy, J.V.; Emmert, R.A. & Patterson, G.K.
Partner: UNT Libraries Government Documents Department

Holdup-related issues in safeguarding of nuclear materials

Description: Residual inventories of special nuclear materials (SNM) remaining in processing facilities (holdup) are recognized as an insidious problem for both safety and safeguards. This paper identifies some of the issues that are of concern to the safeguards community at-large that are related to holdup of SNM in large-scale process equipment. These issues range from basic technologies of SNM production to changing regulatory requirements to meet the needs of safeguarding nuclear materials. Although there are no magic formulas to resolve these issues, there are several initiatives that could be taken in areas of facility design, plant operation, personnel training, SNM monitoring, and regulatory guidelines to minimize the problems of holdup and thereby improve both safety and safeguards at nuclear material processing plants. 8 refs.
Date: March 1, 1988
Creator: Pillay, K.K.S.
Partner: UNT Libraries Government Documents Department

Analytical methods for fissionable material determinations in the nuclear fuel cycle. Progress report, October 1, 1978-September 30, 1979

Description: Work continues on the development of dissolution techniques for difficult-to-dissolve nuclear materials, the development of methods and automated instruments for plutonium, uranium, and thorium determinations, and the preparation of plutonium materials for the Safeguards Analytical Laboratory Evaluation (SALE) program and distribution by the National Bureau of Standards (NBS) as standard reference materials (SRMs). We are measuring the loner plutonium isotope half-lives, evaluating the isotope correlation techniques and the chemistry involved in the mass-spectrometric ion-bead techniques, and analyzing the SALE uranium materials. Completed subtasks include evaluations of various Teflon materials to recommend those acceptable for the dissolution apparatus developed at LASL, investigations of laser-enhanced dissolution of refractory materials, determinations of diverse ion effects on the microgram-sensitive method for determining uranium, fabrication of the first automated controlled-potential coulometric analyzer for determining plutonium, preparation of a /sup 244/Pu material for distribution by NBS as a SRM, and determination of the half-life of /sup 239/Pu. Work has been started on a spectrophotometric method for determining microgram quantities of plutonium, a microcomplexometric titration method for determining uranium, the use of new reagents for separations of plutonium, the preparation and packaging of a new lot of high-purity plutonium metal for distribution by NBS as a plutonium chemical SRM, and determination of half-lives of other plutonium isotopes.
Date: March 1, 1980
Creator: Waterbury, G.R. (comp.)
Partner: UNT Libraries Government Documents Department

Federal Accounting Standards Advisory Board: Technical Amendments to Accounting Standards for Direct Loans and Loan Guarantees in Statement of Federal Financial Accounting Standards No. 2

Description: Other written product issued by the General Accounting Office with an abstract that begins "This publication presents technical amendments to portions of the Statement of Federal Financial Accounting Standards No. 2."
Date: March 1, 2001
Creator: United States. General Accounting Office.
Partner: UNT Libraries Government Documents Department

Supplement to the annual energy outlook 1994

Description: This report is a companion document to the Annual Energy Outlook 1994 (AEO94), (DOE/EIA-0383(94)), released in Jan. 1994. Part I of the Supplement presents the key quantitative assumptions underlying the AEO94 projections, responding to requests by energy analysts for additional information on the forecasts. In Part II, the Supplement provides regional projections and other underlying details of the reference case projections in the AEO94. The AEO94 presents national forecasts of energy production, demand and prices through 2010 for five scenarios, including a reference case and four additional cases that assume higher and lower economic growth and higher and lower world oil prices. These forecasts are used by Federal, State, and local governments, trade associations, and other planners and decisionmakers in the public and private sectors.
Date: March 1, 1994
Creator: United States. Department of Energy. Energy Information Administration
Partner: UNT Libraries Government Documents Department

Measurement of the single top production cross section in proton-antiproton collisions at 1.96 TeV

Description: This thesis describes a search for singly produced top quarks via an electroweak vertex in head-on proton-antiproton collisions at a center of mass energy of √s = 1.96 TeV. The analysis uses a total of 2.3 fb<sup>-1</sup> of data collected with the D0 detector at Fermilab, corresponding to two different run periods of the Tevatron collider. Two channels contribute to single top quark production at the Tevatron, the s-channel and the t-channel. In the s-channel, a virtual W boson is produced from the aniquilation of a quark and an antiquark and a top and a bottom quarks are produced from the W decay. The top quark decays almost exclusively into a W boson and a bottom quark. Final states are considered in which the W boson decays leptonically into an electron or a muon plus a neutrino. Thus, at the detector level, the final state characterizing the s-channel contains one lepton, missing energy accounting for the neutrino, and two jets from the two bottom quarks. In the t-channel, the final state has an additional jet coming from a light quark. Clearly, a precise reconstruction of the events requires a precise measurement of the energy of the jets. A multivariate technique, Bayesian neural networks, is used to extract the single top signal from the overwhelming background still left after event selection. A Bayesian likelihood probability is then computed to measure the single top cross section. Assuming the observed excess is due to single top events, the measured single top quark production cross section is σ(p$\bar{p}$ → tb + X, tqb + X) = 4.70<sup>+1.18</sup><sub>-0.93</sub> pb. The observed excess is associated with a p-value of (3.2 ± 2.3) x 10<sup>-8</sup>, assuming the background-only hypothesis. This p-value corresponds to an excess over background of 5.4 standard deviations for a Gaussian density. The p-value ...
Date: March 25, 2010
Creator: Tanasijczuk, Andres Jorge
Partner: UNT Libraries Government Documents Department