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Measurement of B(d) mixing using opposite-side flavor tagging (open access)

Measurement of B(d) mixing using opposite-side flavor tagging

We report on a measurement of the B{sub d}{sup 0} mixing frequency and the calibration of an opposite-side flavor tagger in the D0 experiment. Various properties associated with the b quark on the opposite side of the reconstructed B meson are combined using a likelihood-ratio method into a single variable with enhanced tagging power. Its performance is tested with data, using a large sample of reconstructed semileptonic B {yields} {mu}D{sup 0} X and B {yields} {mu}D* X decays, corresponding to an integrated luminosity of approximately 1 fb{sup -1}. The events are divided into groups depending on the value of the combined tagging variable, and an independent analysis is performed in each group. Combining the results of these analyses, the overall effective tagging power is found to be {var_epsilon}{prime}D{sup 2} = (2.48 {+-} 0.21{sub -0.06}{sup +0.08})%. The measured B{sub d}{sup 0} mixing frequency {Delta}m{sub d} = 0.506 {+-} 0.020 (stat) {+-} 0.016 (syst) ps{sup -1} is in good agreement with the world average value.
Date: September 1, 2006
Creator: Abazov, V. M.; Abbott, B.; Abolins, M.; Acharya, B. S.; Adams, M.; Adams, T. et al.
Object Type: Article
System: The UNT Digital Library
Measurement of the CP-violation parameter of B0 mixing and decay with p anti-p ---> mu mu X data (open access)

Measurement of the CP-violation parameter of B0 mixing and decay with p anti-p ---> mu mu X data

The authors measure the dimuon charge asymmetry A in p{bar p} collisions at a center of mass energy {radical}s 1960 GeV. The data was recorded with the D0 detector and corresponds to an integrated luminosity of approximately 1.0 fb{sup -1}. Assuming that the asymmetry A is due to asymmetric B{sup 0} {leftrightarrow} {bar B}{sup 0} mixing and decay, they extract the CP-violation parameter of B{sup 0} mixing and decay: R({epsilon}{sub B{sup 0}}/1) + |{epsilon}{sub B{sup 0}}|{sup 2} = A{sub B{sup 0}}/4 = -0.0023 {+-} 0.0011(stat) {+-} 0.0008(syst). A{sub B{sup 0}} is the dimuon charge asymmetry from decays of B{sup 0}{bar B}{sup 0} pairs. The general case, with CP violation in both B{sup 0} and B{sub s}{sup 0} systems, is also considered. Finally they obtain the forward-backward asymmetry that quantifies the tendency of {mu}{sup +} to go in the proton direction and {mu}{sup -} to go in the anti-proton direction. The results are consistent with the standard model and constrain new physics.
Date: September 1, 2006
Creator: Abazov, V. M.; Abbott, B.; Abolins, M.; Acharya, B. S.; Adams, M.; Adams, T. et al.
Object Type: Article
System: The UNT Digital Library
Measurement of the muon charge asymmetry from W boson decays (open access)

Measurement of the muon charge asymmetry from W boson decays

We present a measurement of the muon charge asymmetry from W boson decays using 0.3 fb{sup -1} of data collected at {radical}s = 1.96 GeV between 2002 and 2004 with the D0 detector at the Fermilab Tevatron p{bar p} Collider. We compare our findings with expectations from next-to-leading-order calculations performed using the CTEQ6.1M and MRST04 NLO parton distribution functions. Our findings can be used to constrain future parton distribution function fits.
Date: September 1, 2007
Creator: Abazov, V. M.; Abbott, B.; Abolins, M.; Acharya, B. S.; Adams, M.; Adams, T. et al.
Object Type: Article
System: The UNT Digital Library
Measurement of the top quark mass in the dilepton channel (open access)

Measurement of the top quark mass in the dilepton channel

We present a measurement of the top quark mass in the dilepton channel based on approximately 370 pb{sup -1} of data collected by the D0 experiment during Run II of the Fermilab Tevatron collider. We employ two different methods to extract the top quark mass. We show that both methods yield consistent results using ensemble tests of events generated with the D0 Monte Carlo simulation. We combine the results from the two methods to obtain a top quark mass m{sub t} = 178.1 {+-} 8.2 GeV. The statistical uncertainty is 6.7 GeV and the systematic uncertainty is 4.8 GeV.
Date: September 1, 2006
Creator: Abazov, V. M.; Abbott, B.; Abolins, M.; Acharya, B. S.; Adams, M.; Adams, T. et al.
Object Type: Article
System: The UNT Digital Library
Measurement of the top quark mass in the lepton+jets final state with the matrix element method (open access)

Measurement of the top quark mass in the lepton+jets final state with the matrix element method

We present a measurement of the top quark mass with the Matrix Element method in the lepton+jets final state. As the energy scale for calorimeter jets represents the dominant source of systematic uncertainty, the Matrix Element likelihood is extended by an additional parameter, which is defined as a global multiplicative factor applied to the standard energy scale. The top quark mass is obtained from a fit that yields the combined statistical and systematic jet energy scale uncertainty.
Date: September 1, 2006
Creator: Abazov, V. M.; Abbott, B.; Abolins, M.; Acharya, B. S.; Adams, M.; Adams, T. et al.
Object Type: Article
System: The UNT Digital Library
Measurement of the W boson helicity in top quark decay at D0 (open access)

Measurement of the W boson helicity in top quark decay at D0

The authors present a measurement of the fraction f{sub +} of right-handed W bosons produced in top quark decays, based on a candidate sample of t{bar t} events in the {ell}+jets and dilepton decay channels corresponding to an integrated luminosity of 370 pb{sup -1} collected by the D0 detector at the Fermilab Tevatron p{bar p} Collider at {radical}s = 1.96 TeV. They reconstruct the decay angle {theta}* for each lepton. By comparing the cos{theta}* distribution from the data with those for the expected background and signal for various values of f{sub +}, they find f{sub +} = 0.056 {+-} 0.080(stat) {+-} 0.057(syst). (f{sub +} < 0.23 at 95% C.L.), consistent with the standard model prediction of f{sub +} = 3.6 x 10{sup -4}.
Date: September 1, 2006
Creator: Abazov, V. M.; Abbott, B.; Abolins, M.; Acharya, B. S.; Adams, M.; Adams, T. et al.
Object Type: Article
System: The UNT Digital Library
Separation of Corn Fiber and Conversion to Fuels and Chemicals Phase II: Pilot-scale Operation (open access)

Separation of Corn Fiber and Conversion to Fuels and Chemicals Phase II: Pilot-scale Operation

The purpose of the Department of Energy (DOE)-supported corn fiber conversion project, “Separation of Corn Fiber and Conversion to Fuels and Chemicals Phase II: Pilot-scale Operation” is to develop and demonstrate an integrated, economical process for the separation of corn fiber into its principal components to produce higher value-added fuel (ethanol and biodiesel), nutraceuticals (phytosterols), chemicals (polyols), and animal feed (corn fiber molasses). This project has successfully demonstrated the corn fiber conversion process on the pilot scale, and ensured that the process will integrate well into existing ADM corn wet-mills. This process involves hydrolyzing the corn fiber to solubilize 50% of the corn fiber as oligosaccharides and soluble protein. The solubilized fiber is removed and the remaining fiber residue is solvent extracted to remove the corn fiber oil, which contains valuable phytosterols. The extracted oil is refined to separate the phytosterols and the remaining oil is converted to biodiesel. The de-oiled fiber is enzymatically hydrolyzed and remixed with the soluble oligosaccharides in a fermentation vessel where it is fermented by a recombinant yeast, which is capable of fermenting the glucose and xylose to produce ethanol. The fermentation broth is distilled to remove the ethanol. The stillage is centrifuged to separate …
Date: September 28, 2007
Creator: Abbas, Charles; Beery, Kyle; Orth, Rick & Zacher, Alan
Object Type: Report
System: The UNT Digital Library
DZero data-intensive computing on the Open Science Grid (open access)

DZero data-intensive computing on the Open Science Grid

High energy physics experiments periodically reprocess data, in order to take advantage of improved understanding of the detector and the data processing code. Between February and May 2007, the DZero experiment has reprocessed a substantial fraction of its dataset. This consists of half a billion events, corresponding to about 100 TB of data, organized in 300,000 files. The activity utilized resources from sites around the world, including a dozen sites participating to the Open Science Grid consortium (OSG). About 1,500 jobs were run every day across the OSG, consuming and producing hundreds of Gigabytes of data. Access to OSG computing and storage resources was coordinated by the SAM-Grid system. This system organized job access to a complex topology of data queues and job scheduling to clusters, using a SAM-Grid to OSG job forwarding infrastructure. For the first time in the lifetime of the experiment, a data intensive production activity was managed on a general purpose grid, such as OSG. This paper describes the implications of using OSG, where all resources are granted following an opportunistic model, the challenges of operating a data intensive activity over such large computing infrastructure, and the lessons learned throughout the project.
Date: September 1, 2007
Creator: Abbott, B.; U., /Oklahoma; Baranovski, A.; Diesburg, M.; Garzoglio, G.; /Fermilab et al.
Object Type: Article
System: The UNT Digital Library
Airborne Dust Cloud Measurements at the INL National Security Test Range (open access)

Airborne Dust Cloud Measurements at the INL National Security Test Range

On July 11, 2007, a surface, high-explosive test (<20,000 lb TNT-equivalent) was carried out at the National Security Test Range (NSTR) on the Idaho National Laboratory (INL) Site. Aircraft-mounted rapid response (1-sec) particulate monitors were used to measure airborne PM-10 concentrations directly in the dust cloud and to develop a PM-10 emission factor that could be used for subsequent tests at the NSTR. The blast produced a mushroom-like dust cloud that rose approximately 2,500–3,000 ft above ground level, which quickly dissipated (within 5 miles of the source). In general, the cloud was smaller and less persistence than expected, or that might occur in other areas, likely due to the coarse sand and subsurface conditions that characterize the immediate NSTR area. Maximum short time-averaged (1-sec) PM-10 concentrations at the center of the cloud immediately after the event reached 421 µg m-3 but were rapidly reduced (by atmospheric dispersion and fallout) to near background levels (~10 µg m-3) after about 15 minutes. This occurred well within the INL Site boundary, about 8 km (5 miles) from the NSTR source. These findings demonstrate that maximum concentrations in ambient air beyond the INL Site boundary (closest is 11.2 km from NSTR) from these types …
Date: September 1, 2007
Creator: Abbott, Michael L.; Stanley, Norm; Radke, Larry & Smeltzer, Charles
Object Type: Report
System: The UNT Digital Library
Environmental Sampling FY01 Annual Report - Understanding the Movement of Mercury in the Environmental Surrounding the INEEL (open access)

Environmental Sampling FY01 Annual Report - Understanding the Movement of Mercury in the Environmental Surrounding the INEEL

Environmental fate and transport of the toxic air pollutant mercury (Hg) is currently a high-priority regional concern for the INEEL, and national and global concern for the U.S. Environmental Protection Agency (EPA). At the INEEL’s Idaho Nuclear Technology and Engineering Center (INTEC), significant quantities (est. 40 kg/year) of Hg may have been released over 37 years of Environmental Management’s (EM) High-Level Waste (HLW) treatment operations. The EPA is very concerned about the continued global buildup of Hg in the atmosphere and aquatic ecosystems, and has recently invested heavily in Hg research to better understand its complex environmental cycling.1,2 The Environmental Sampling work began in FY99 as a joint INEEL/U.S. Geological Survey (USGS) field research effort to (a) better understand the fate and potential impacts of Hg emissions from the INEEL’s HLW treatment operations (operational component) and (b) contribute at a national level to the scientific understanding of local, regional, and global Hg fate and transport (research component). The USGS contributed snow sampling support in the field (Water Resources Division, Salt Lake City) and laboratory analysis of all samples (Wisconsin District Mercury Research Laboratory).
Date: September 1, 2001
Creator: Abbott, Michael Lehman
Object Type: Report
System: The UNT Digital Library
Trace Elements and Common Ions in Southeastern Idaho Snow: Regional Air Pollutant Tracers for Source Area Emissions (open access)

Trace Elements and Common Ions in Southeastern Idaho Snow: Regional Air Pollutant Tracers for Source Area Emissions

Snow samples were collected in southeastern Idaho over two winters to assess trace elements and common ions concentrations in air pollutant fallout across the region. The objectives were to: 1) develop sampling and analysis techniques that would produce accurate measurements of a broad suite of elements and ions in snow, 2) identify the major elements in regional fallout and their spatial and temporal trends, 3) determine if there are unique combinations of elements that are characteristic to the major source areas in the region (source profiles), and 4) use pattern recognition and multivariate statistical techniques (principal component analysis and classical least squares regression) to investigate source apportionment of the fallout to the major source areas. In the winter of 2000-2001, 250 snow samples were collected across the region over a 4-month period and analyzed in triplicate using inductively-coupled plasma mass spectrometry (ICP-MS) and ion chromatography (IC). Thirty-nine (39) trace elements and 9 common ions were positively identified in most samples. The data were analyzed using pattern recognition tools in the software, Pirouette® (Infometrix, Inc.). These results showed a large crustal component (Al, Zn, Mn, Ba, and rare earth elements), an overwhelming contribution from phosphate processing facilities located outside Pocatello in …
Date: September 1, 2002
Creator: Abbott, Michael Lehman; Einerson, Jeffrey James; Schuster, Paul & Susong, David D.
Object Type: Article
System: The UNT Digital Library
The Framework for Approximate Queries on Simulation Data (open access)

The Framework for Approximate Queries on Simulation Data

AQSim is a system intended to enable scientists to query and analyze a large volume of scientific simulation data. The system uses the state of the art in approximate query processing techniques to build a novel framework for progressive data analysis. These techniques are used to define a multi-resolution index, where each node contains multiple models of the data. The benefits of these models are two-fold: (1) they are compact representations, reconstructing only the information relevant to the analysis, and (2) the variety of models capture different aspects of the data which may be of interest to the user but are not readily apparent in their raw form. To be able to deal with the data interactively, AQSim allows the scientist to make an informed tradeoff between query response accuracy and time. In this paper, we present the framework of AQSim with a focus on its architectural design. We also show the results from an initial proof-of-concept prototype developed at LLNL. The presented framework is generic enough to handle more than just simulation data.
Date: September 27, 2001
Creator: Abdulla, G.; Baldwin, C.; Critchlow, T.; Kamimura, R.; Lee, B.; Musick, R. et al.
Object Type: Article
System: The UNT Digital Library
THE IMPACT OF TRACE ADDITIVES ON THE APPARENT SOLUBILITY  OF HYDROGEN IN HEAVEY OIL AND RELATED FEEDSTOCKS AT LOW AND HIGH TEMPERATURES (open access)

THE IMPACT OF TRACE ADDITIVES ON THE APPARENT SOLUBILITY OF HYDROGEN IN HEAVEY OIL AND RELATED FEEDSTOCKS AT LOW AND HIGH TEMPERATURES

A systematic investigation was conducted to provide an accurate determination of hydrogen solubility in liquid media in temperatures in the range of 25-250 C and pressures in the range of 0.5-8 MPa. Results were obtained by an indirect gas solubility measurement method. The method was intended for use with high-resolution camera. The hydrogen solubility measurements were indirect and were based on pressure changes at constant temperature and measured volumes. Since the volume of the view cell was fixed the volume available for the vapor phase could be determined by measuring the location of the liquid-vapor interface. The interface was located to within the height of one pixel using high-resolution camera, which added {+-} 0.4 ml to the uncertainty of the vapor volume. Liquid-liquid interface locations were measured with equal precision. The accuracy of the method was illustrated through hydrogen solubility measurements in hexadecane and tetralin, which were in close agreement with the values available in the literature. Hydrogen solubilities in Athabasca bitumen vacuum bottoms (ABVB) were reported over a broad range of temperatures (80-250 C) and pressures (0.5-8 MPa).
Date: September 2002
Creator: Abedi, J.
Object Type: Report
System: The UNT Digital Library
Electric Reliability: Options for Electric Transmission Infrastructure Improvements (open access)

Electric Reliability: Options for Electric Transmission Infrastructure Improvements

The electric utility industry is inherently capital intensive. At the same time, the industry must operate under a changing and sometimes unpredictable regulatory system at both the federal and state level. The Energy Policy Act of 2005 has set in place government activities intended to relieve congestion on the transmission system. Several factors have contributed to the lack of new transmission capacity; these are outlined within this report. This report also discusses earlier pieces of energy legislation.
Date: September 20, 2006
Creator: Abel, Amy
Object Type: Report
System: The UNT Digital Library
Electric Reliability: Options for Electric Transmission Infrastructure Improvements (open access)

Electric Reliability: Options for Electric Transmission Infrastructure Improvements

The electric utility industry is inherently capital intensive. At the same time, the industry must operate under a changing and sometimes unpredictable regulatory system at both the federal and state level. The Energy Policy Act of 2005 has set in place government activities intended to relieve congestion on the transmission system. Several factors have contributed to the lack of new transmission capacity; these are outlined within this report. This report also discusses earlier pieces of energy legislation.
Date: September 20, 2006
Creator: Abel, Amy
Object Type: Report
System: The UNT Digital Library
Electric Reliability: Options for Electric Transmission Infrastructure Improvements (open access)

Electric Reliability: Options for Electric Transmission Infrastructure Improvements

The electric utility industry is inherently capital intensive. At the same time, the industry must operate under a changing and sometimes unpredictable regulatory system at both the federal and state level. The Energy Policy Act of 2005 has set in place government activities intended to relieve congestion on the transmission system. Several factors have contributed to the lack of new transmission capacity; these are outlined within this report. This report also discusses earlier pieces of energy legislation.
Date: September 20, 2006
Creator: Abel, Amy
Object Type: Report
System: The UNT Digital Library
Electricity: The Road Toward Restructuring (open access)

Electricity: The Road Toward Restructuring

The Public Utility Holding Company Act of 1935 (PUHCA) and the Federal Power Act (FPA) were enacted to eliminate unfair practices and other abuses by electricity and gas holding companies by requiring federal control and regulation of interstate public utility holding companies. Comprehensive energy legislation has passed the House and Senate. The House passed H.R. 6 on April 11, 2003. On July 31, 2003, the Senate suspended debate on S. 14, inserted the text of H.R. 4 (107th Congress) as a substitute, and passed H.R. 6. A conference agreement was reached November 17, 2003, and passed by the House the next day. H.R. 6 includes an electricity title that would, in part, repeal PUHCA, would prospectively repeal the mandatory purchase requirement under PURPA, and would create an electric reliability organization. On June 15, 2004, H.R. 4503, a comprehensive energy policy bill, passed the House.
Date: September 7, 2001
Creator: Abel, Amy & Parker, Larry
Object Type: Report
System: The UNT Digital Library
Electricity: The Road Toward Restructuring (open access)

Electricity: The Road Toward Restructuring

The Public Utility Holding Company Act of 1935 (PUHCA) and the Federal Power Act (FPA) were enacted to eliminate unfair practices and other abuses by electricity and gas holding companies by requiring federal control and regulation of interstate public utility holding companies. Comprehensive energy legislation has passed the House and Senate. The House passed H.R. 6 on April 11, 2003. On July 31, 2003, the Senate suspended debate on S. 14, inserted the text of H.R. 4 (107th Congress) as a substitute, and passed H.R. 6. A conference agreement was reached November 17, 2003, and passed by the House the next day. H.R. 6 includes an electricity title that would, in part, repeal PUHCA, would prospectively repeal the mandatory purchase requirement under PURPA, and would create an electric reliability organization. On June 15, 2004, H.R. 4503, a comprehensive energy policy bill, passed the House.
Date: September 30, 2004
Creator: Abel, Amy & Parker, Larry
Object Type: Report
System: The UNT Digital Library
Electricity: The Road Toward Restructuring (open access)

Electricity: The Road Toward Restructuring

The Public Utility Holding Company Act of 1935 (PUHCA) and the Federal Power Act (FPA) were enacted to eliminate unfair practices and other abuses by electricity and gas holding companies by requiring federal control and regulation of interstate public utility holding companies. Comprehensive energy legislation has passed the House and Senate. The House passed H.R. 6 on April 11, 2003. On July 31, 2003, the Senate suspended debate on S. 14, inserted the text of H.R. 4 (107th Congress) as a substitute, and passed H.R. 6. A conference agreement was reached November 17, 2003, and passed by the House the next day. H.R. 6 includes an electricity title that would, in part, repeal PUHCA, would prospectively repeal the mandatory purchase requirement under PURPA, and would create an electric reliability organization. On June 15, 2004, H.R. 4503, a comprehensive energy policy bill, passed the House.
Date: September 30, 2003
Creator: Abel, Amy & Parker, Larry
Object Type: Report
System: The UNT Digital Library
Abilene Philharmonic Playbill: September 16-October 28, 2000 (open access)

Abilene Philharmonic Playbill: September 16-October 28, 2000

Program for an Abilene Philharmonic concert that ran from September 16th to October 28th during the 50th season. It includes information about the pieces performed, artists and musicians, and advertising from local companies.
Date: September 2000
Creator: Abilene Philharmonic
Object Type: Pamphlet
System: The Portal to Texas History
Abilene Philharmonic Playbill: September 15-October 27, 2001 (open access)

Abilene Philharmonic Playbill: September 15-October 27, 2001

Program for an Abilene Philharmonic concert that ran from September 15th to October 27th (classical concert) during the 51st season. It includes information about the pieces performed, artists and musicians, and advertising from local companies.
Date: September 2001
Creator: Abilene Philharmonic
Object Type: Book
System: The Portal to Texas History
Abilene Philharmonic Playbill: September 14, 2002 (open access)

Abilene Philharmonic Playbill: September 14, 2002

Program for an Abilene Philharmonic concert that ran from September 14th to October 26th during the 52nd season. It includes information about the pieces performed, artists and musicians, and advertising from local companies.
Date: September 2002
Creator: Abilene Philharmonic
Object Type: Pamphlet
System: The Portal to Texas History
Abilene Philharmonic Playbill: September 20-October 18, 2003 (open access)

Abilene Philharmonic Playbill: September 20-October 18, 2003

Program for an Abilene Philharmonic concert that ran from September 20th to October 18th during the 54th season. It includes information about the pieces performed, artists and musicians, and advertising from local companies.
Date: September 2003
Creator: Abilene Philharmonic
Object Type: Pamphlet
System: The Portal to Texas History
Abilene Philharmonic Playbill: September 18-October 30, 2004 (open access)

Abilene Philharmonic Playbill: September 18-October 30, 2004

Program for an Abilene Philharmonic concert that ran from September 18th to October 30th during the 55th season. It includes information about the pieces performed, artists and musicians, and advertising from local companies.
Date: September 2004
Creator: Abilene Philharmonic
Object Type: Pamphlet
System: The Portal to Texas History