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First direct two-sided bound on the B0(s) oscillation frequency (open access)

First direct two-sided bound on the B0(s) oscillation frequency

The authors report the first direct two-sided bound on the B{sub s}{sup 0} oscillation frequency using a large sample of B{sub s}{sup 0} semileptonic decays corresponding to approximately 1 fb{sup -1} of integrated luminosity collected by the D0 experiment in 2002-2006 during Run II of the Fermilab Tevatron Collider. The flavor (i.e., B{sub s}{sup 0} or B{sub s}{sup 0}) of the B{sub s}{sup 0} meson at the time of production was found using an opposite-side tagging technique, and the flavor at the time of decay was determined from the charge of the muon in the partially reconstructed decay B{sub s}{sup 0} {yields} {mu}{sup +} D{sub s}{sup -}X, D{sub s}{sup -} {yields} {phi}{pi}{sup -}, {phi} {yields} K{sup +}K{sup -}. A likelihood scan over the oscillation frequency, {Delta}m{sub s}, gives a most probable value of 19 ps{sup -1} and a range of 17 < {Delta}m{sub s} < 21 ps{sup -1} at the 90% C.L. At {Delta}m{sub s} = 19 ps{sup -1}, the amplitude method yields a result that deviates from the hypothesis of an oscillation amplitude of zero by 2.5 standard deviations, corresponding to a two-sided C.L. of 1%.
Date: March 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 B(t ---> Wb)/B(t ---> Wq) at s**(1/2) = 1.96-TeV (open access)

Measurement of B(t ---> Wb)/B(t ---> Wq) at s**(1/2) = 1.96-TeV

The authors present the measurement of R = {Beta}(t {yields} Wb)/{Beta}(t {yields} Wq) in p{bar p} collisions at {radical}s = 1.96 TeV, using 230 pb{sup -1} of data collected by the D0 experiment at the Fermilab Tevatron Collider. They fit simultaneously R and the number (N{sub t{bar t}}) of selected top quark pairs (t{bar t}), to the number of identified b-quark jets in events with one electron or one muon, three or more jets, and high transverse energy imbalance. To improve sensitivity, kinematical properties of events with no identified b-quark jets are included in the fit. They measure R = 1.03{sub -0.17}{sup +0.19}(stat+syst), in good agreement with the standard model. They set lower limits of R > 0.61 and |V{sub tb}| > 0.78 at 95% confidence level.
Date: March 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
Final Report: Developing Liquid Protection Schemes for Fusion Energy Reactor First Walls (open access)

Final Report: Developing Liquid Protection Schemes for Fusion Energy Reactor First Walls

Over the last year, the Georgia Tech group has experimentally studied vertical turbulent sheets of water issuing downwards into atmospheric pressure air at Reynolds numbers Re = U{sub 0}{delta}/{nu} = 53,000 and 120,000 and Weber numbers We = {rho}U{sub o} {sup 2}{delta}/{sigma} = 2,900 and 18,000, respectively. Here, U{sub o} is the average jet speed, {delta} is the jet thickness (short dimension) at the nozzle exit ({delta} = 1 cm), and {nu}, {rho} and {sigma} are the kinematic viscosity and density of water and the surface tension at the air-water interface, respectively. These Re and We values are about 50% and 20% of the prototypical values for HYLIFE-II, respectively. In this report, the flow coordinate system is defined so that the origin is at the center of the nozzle exit, with the x-axis along the flow direction, the y-axis along the long dimension of the nozzle, and the z-axis along the short dimension of the nozzle (cf. Fig. 1). During the final year of this project, we have made three contributions in the area of thermal-hydraulics of thick liquid protection, namely: (1) Experimentally demonstrated that removing as little as 1% of the total mass flux using boundary-layer (BL) cutting can …
Date: March 29, 2006
Creator: Abdel-Khalik, Minami Yoda Said I.
Object Type: Report
System: The UNT Digital Library
Measurement of the B(c)+ meson lifetime using B(c)+ ---> J/psi e+ nu(e) (open access)

Measurement of the B(c)+ meson lifetime using B(c)+ ---> J/psi e+ nu(e)

The authors present a measurement of the B{sub c}{sup +} meson lifetime in the semileptonic decay mode B{sub c}{sup +} {yields} J/{psi}e{sup +}{nu}{sub e} using the CDF II detector at the Fermilab Tevatron Collider. From a sample of about 360 pb{sup -1} of p{bar p} collisions at {radical}s = 1.96 TeV, they reconstruct J/{psi}e{sup +} pairs with invariant mass in the kinematically allowed range 4 < M{sub J/{psi}e} < 6 GeV/c{sup 2}. A fit to the decay-length distribution of 238 signal events yields a measured B{sub c}{sup +} meson lifetime of 0.463{sub -0.065}{sup +0.073}(stat) {+-} 0.036(syst) ps.
Date: March 1, 2006
Creator: Abulencia, A.; Acosta, D.; Adelman, Jahred A.; Affolder, T.; Akimoto, T.; Albrow, M.G. et al.
Object Type: Article
System: The UNT Digital Library
Measurement of the t anti-t production cross section in p anti-p collisions at s**(1/2) = 1.96-TeV using missing E(T) + jets events with secondary vertex b-tagging (open access)

Measurement of the t anti-t production cross section in p anti-p collisions at s**(1/2) = 1.96-TeV using missing E(T) + jets events with secondary vertex b-tagging

The authors present a measurement of the t{bar t} production cross section in p{bar p} collisions at {radical}s = 1.96 TeV which uses events with an inclusive signature of significant missing transverse energy and jets. This is the first measurement which makes no explicit lepton identification requirements, so that sensitivity to W {yields} {tau}{nu} decays is maintained. Heavy flavor jets from top quark decay are identified with a secondary vertex tagging algorithm. From 311 pb{sup -1} of data collected by the Collider Detector at Fermilab they measure a production cross section of 5.8 {+-} 1.2(stat.){sub -0.7}{sup +0.9}(syst.) pb for a top quark mass of 178 GeV/c{sup 2}, in agreement with previous determinations and standard model predictions.
Date: March 1, 2006
Creator: Abulencia, A.; Acosta, D.; Adelman, Jahred A.; Affolder, T.; Akimoto, T.; Albrow, M.G. et al.
Object Type: Article
System: The UNT Digital Library
Search for high-mass resonances decaying to e mu in p anti-p collisions at s**(1/2) = 1.96-TeV (open access)

Search for high-mass resonances decaying to e mu in p anti-p collisions at s**(1/2) = 1.96-TeV

The authors describe a general search for resonances decaying to a neutral e{mu} final state in p{bar p} collisions at a center-of-mass energy of 1.96 TeV. Using a data sample representing 344 pb{sup -1} of integrated luminosity recorded by the CDF II experiment, they compare Standard Model predictions with the number of observed events for invariant masses between 50 and 800 GeV/c{sup 2}. Finding no significant excess (5 events observed vs. 7.7 {+-} 0.8 expected for M{sub e{mu}} > 100 GeV/c{sup 2}), they set limits on sneutrino and Z{prime} masses as functions of lepton family number violating couplings.
Date: March 1, 2006
Creator: Abulencia, A.; Acosta, D.; Adelman, Jahred A.; Affolder, T.; Akimoto, T.; Albrow, M.G. et al.
Object Type: Article
System: The UNT Digital Library
Finite Cosmology and a CMB Cold Spot (open access)

Finite Cosmology and a CMB Cold Spot

The standard cosmological model posits a spatially flat universe of infinite extent. However, no observation, even in principle, could verify that the matter extends to infinity. In this work we model the universe as a finite spherical ball of dust and dark energy, and obtain a lower limit estimate of its mass and present size: the mass is at least 5 x 10{sup 23}M{sub {circle_dot}} and the present radius is at least 50 Gly. If we are not too far from the dust-ball edge we might expect to see a cold spot in the cosmic microwave background, and there might be suppression of the low multipoles in the angular power spectrum. Thus the model may be testable, at least in principle. We also obtain and discuss the geometry exterior to the dust ball; it is Schwarzschild-de Sitter with a naked singularity, and provides an interesting picture of cosmogenesis. Finally we briefly sketch how radiation and inflation eras may be incorporated into the model.
Date: March 20, 2006
Creator: Adler, R. J.; Bjorken, J. D. & Overduin, J.M.
Object Type: Report
System: The UNT Digital Library
TASK TECHNICAL AND QUALITY ASSURANCE PLAN FOR OUT-OF-TANK DESTRUCTION OF TETRAPHENYLBORATE VIA WET AIR OXIDATION TECHNOLOGY: PHASE I - BENCH SCALE TESTS (open access)

TASK TECHNICAL AND QUALITY ASSURANCE PLAN FOR OUT-OF-TANK DESTRUCTION OF TETRAPHENYLBORATE VIA WET AIR OXIDATION TECHNOLOGY: PHASE I - BENCH SCALE TESTS

Tank 48H return to service is critical to the processing of high level waste (HLW) at Savannah River Site (SRS). Liquid Waste Disposition (LWD) management has the goal of returning Tank 48H to routine service by January 2010 or as soon as practical. Tank 48H currently holds legacy material containing organic tetraphenylborate (TPB) compounds from the operation of the In-Tank Precipitation process. This material is not compatible with the waste treatment facilities at SRS and must be removed or undergo treatment to destroy the organic compounds before the tank can be returned to Tank Farm service. Tank 48H currently contains {approx}240,000 gallons of alkaline slurry with about 2 wt % potassium and cesium tetraphenylborate (KTPB and CsTPB). The main radioactive component in Tank 48H is {sup 137}Cs. The waste also contains {approx}0.15 wt % Monosodium Titanate (MST) which has adsorbed {sup 90}Sr, U, and Pu isotopes. A System Engineering Evaluation of technologies/ideas for the treatment of TPB identified Wet Air Oxidation (WAO) as a leading alternative technology to the baseline aggregation approach. Over 75 technologies/ideas were evaluated overall. Forty-one technologies/ideas passed the initial screening evaluation. The 41 technologies/ideas were then combined to 16 complete solutions for the disposition of TPB …
Date: March 31, 2006
Creator: Adu-Wusu, K
Object Type: Report
System: The UNT Digital Library
Scale-Up and Demonstration of Fly Ash Ozonation Technology (open access)

Scale-Up and Demonstration of Fly Ash Ozonation Technology

The disposal of fly ash from the combustion of coal has become increasingly important. When the fly ash does not meet the required specification for the product or market intended, it is necessary to beneficiate it to achieve the desired quality. This project, conducted at PPL's Montour SES, is the first near full-scale ({approx}10 ton/day), demonstration of ash ozonation technology. Bituminous and sub bituminous ashes, including two ash samples that contained activated carbon, were treated during the project. Results from the tests were very promising. The ashes were successfully treated with ozone, yielding concrete-suitable ash quality. Preliminary process cost estimates indicate that capital and operating costs to treat unburned carbon are competitive with other commercial ash beneficiation technologies at a fraction of the cost of lost sales and/or ash disposal costs. This is the final technical report under DOE Cooperative Agreement No.: DE-FC26-03NT41730.
Date: March 1, 2006
Creator: Afonso, Rui; Hurt, R. & Kulaots, I.
Object Type: Report
System: The UNT Digital Library
Modeling the Cathodic Region in Crevice Corrosion Under a Thin Electrolyte Film Including Particulates (open access)

Modeling the Cathodic Region in Crevice Corrosion Under a Thin Electrolyte Film Including Particulates

Crevice corrosion may be limited by the capacity of the external cathodic region to support anodic dissolution currents within the crevice. The analysis here focuses on behavior of metal surfaces covered by a thin ({approx}microns) layer of the electrolyte film including particulates. The particulates can affect the cathode current capacity (I{sub total}) by increasing the solution resistance (''volume effect'') and by decreasing the electrode area (''surface effect''). In addition, there can be particulate effects on oxygen reduction kinetics and oxygen transport. This work simulates and characterizes the effect of a uniform particulate monolayer on the cathode current capacity for steady state conditions in the presence of a thin electrolyte film. Particulate configurations with varying particle size, shape, arrangement, volume fraction, and electrode area coverage were numerically modeled as a function of the properties of the system. It is observed that the effects of particles can be fully accounted for in terms of two corrections: the volume blockage effect on the electrolyte resistivity can be correlated using Bruggeman's equation, and the electrode coverage effect can be modeled in terms of a simple area correction to the kinetics expression. For the range of parameters analyzed, applying these two correction factors, cathodes covered …
Date: March 14, 2006
Creator: Agarwal, A. S.; Landau, U.; Shan, X. & Payer, J. H.
Object Type: Report
System: The UNT Digital Library
Ultrahigh Efficiency Multiband Solar Cells Final Report forDirector's Innovation Initiative Project DII-2005-1221 (open access)

Ultrahigh Efficiency Multiband Solar Cells Final Report forDirector's Innovation Initiative Project DII-2005-1221

The unique properties of the semiconductor ZnTeO were explored and developed to make multiband solar cells. Like a multijunction cell, multiband solar cells use different energy gaps to convert the majority of the solar spectrum to electrical current while minimizing losses due to heating. Unlike a multijunction cell, this is accomplished within a single material in a multiband cell. ZnTe{sub 1-x}O{sub x} films with x up to 2% were synthesized and shown to have the requisite unique band structure (2 conduction bands) for multiband function. Prototype solar cells based on an n-type ZnTe{sub 1-x}O{sub x} multiband top layer and a p-type ZnTe substrate were fabricated. Contacts to the cell and the series resistance of the substrate were identified as challenges for good electrical performance. Both photovoltage and small photocurrents were demonstrated under AMO illumination. A second semiconductor system, GaN{sub x}As{sub 1-y-x}P{sub y}, was shown to have multiband function. This alloy system may have the greatest potential to realize the promise of high efficiency multiband solar cells because of the relatively advanced technology base that exists for the manufacturing of III-V-alloy-based IC and opto-electronic devices (including multijunction solar cells).
Date: March 29, 2006
Creator: Ager, Joel W., III; Walukiewicz, W. & Yu, Kin Man
Object Type: Report
System: The UNT Digital Library
U.S.-European Union Trade Relations: Issues and Policy Challenges (open access)

U.S.-European Union Trade Relations: Issues and Policy Challenges

None
Date: March 17, 2006
Creator: Ahearn, Raymond J.
Object Type: Report
System: The UNT Digital Library
The Scientific Publications of Richard H. Dalitz, FRS (1925-2006) (open access)

The Scientific Publications of Richard H. Dalitz, FRS (1925-2006)

Professor Richard H. Dalitz passed away on January 13, 2006. He was almost 81 years old and his outstanding contributions are intimately connected to some of the major breakthroughs of the 20th century in particle and nuclear physics. These outstanding contributions go beyond the Dalitz Plot, Dalitz Pair and CDD poles that bear his name. He pioneered the theoretical study of strange baryon resonances, of baryon spectroscopy in the quark model, and of hypernuclei, to all of which he made lasting contributions. His formulation of the ''{theta} - {tau} puzzle'' led to the discovery that parity is not a symmetry of the weak interactions. A brief scientific evaluation of Dalitz's major contributions to particle and nuclear physics is hereby presented, followed by the first comprehensive list of his scientific publications, as assembled from several sources. The list is divided into two categories: the first, main part comprises Dalitz's research papers and reviews, including topics in the history of particle physics, biographies and reminescences; the second part lists book reviews, public lectures and obituaries authored by Dalitz, and books edited by him. This provides the first necessary step towards a more systematic research of the Dalitz heritage in modern physics.
Date: March 29, 2006
Creator: Aitchison, Ian J.R.; Close, Frank E.; Gal, Avraham & Millener, D.John
Object Type: Report
System: The UNT Digital Library
Chemical Depth Profiling from Neutron Reflectometry (open access)

Chemical Depth Profiling from Neutron Reflectometry

The material profile of a thin film can be analyzed by placing the film on a substrate and by sending a neutron beam onto it at various angles of incidence. Technically, the scattering length density of the film needs to be determined as a function of depth. A reflectometer is used to measure the amount of reflection (reflectivity) as a function of the angle of incidence. Mathematically, this is equivalent to sending the neutron beam onto the film at every energy but at a fixed angle of incidence. The film profile needs to be recovered from the measured reflectivity data. Unfortunately, the unique recovery is impossible, and many distinct unrelated profiles may correspond to the same reflectivity data. In our DOE/EPSCoR sponsored research, we have developed an analytical method to uniquely recover the profile of a thin film from the measured reflectivity data. We have shown that by taking reflectivity measurements with two different substrates, one can uniquely determine the film profile. Previously, it was known that one could uniquely recover the profile by taking reflectivity measurements with three different substrates, and our findings indicate that the same goal can be accomplished by using fewer measurements. At Mississippi State University …
Date: March 21, 2006
Creator: Aktosun, Tuncay
Object Type: Report
System: The UNT Digital Library
Smart Energy Management and Control for Fuel Cell Based Micro-Grid Connected Neighborhoods (open access)

Smart Energy Management and Control for Fuel Cell Based Micro-Grid Connected Neighborhoods

Fuel cell power generation promises to be an efficient, pollution-free, reliable power source in both large scale and small scale, remote applications. DOE formed the Solid State Energy Conversion Alliance with the intention of breaking one of the last barriers remaining for cost effective fuel cell power generation. The Alliance’s goal is to produce a core solid-state fuel cell module at a cost of no more than $400 per kilowatt and ready for commercial application by 2010. With their inherently high, 60-70% conversion efficiencies, significantly reduced carbon dioxide emissions, and negligible emissions of other pollutants, fuel cells will be the obvious choice for a broad variety of commercial and residential applications when their cost effectiveness is improved. In a research program funded by the Department of Energy, the research team has been investigating smart fuel cell-operated residential micro-grid communities. This research has focused on using smart control systems in conjunction with fuel cell power plants, with the goal to reduce energy consumption, reduce demand peaks and still meet the energy requirements of any household in a micro-grid community environment. In Phases I and II, a SEMaC was developed and extended to a micro-grid community. In addition, an optimal configuration was …
Date: March 15, 2006
Creator: Alam, Dr. Mohammad S.
Object Type: Report
System: The UNT Digital Library
Formulations for the "Characterization of unique compounds in explosives" project (open access)

Formulations for the "Characterization of unique compounds in explosives" project

None
Date: March 15, 2006
Creator: Alcaraz, A. & Dougan, A.
Object Type: Report
System: The UNT Digital Library
QUESTIONNAIRE ON THE CAPABILITIES OF MEMBER STATES REGARDING THE ANALYSIS OF BIOMEDICAL SAMPLES (open access)

QUESTIONNAIRE ON THE CAPABILITIES OF MEMBER STATES REGARDING THE ANALYSIS OF BIOMEDICAL SAMPLES

None
Date: March 27, 2006
Creator: Alcaraz, A. & Gregg, H.
Object Type: Report
System: The UNT Digital Library
DEVELOPMENT OF A CO2 SEQUESTRATION MODULE BY INTEGRATING MINERAL ACTIVATION AND AQUEOUS CARBONATION (open access)

DEVELOPMENT OF A CO2 SEQUESTRATION MODULE BY INTEGRATING MINERAL ACTIVATION AND AQUEOUS CARBONATION

Mineral carbonation provides a potential option for the long-term storage of carbon dioxide. Serpentine has been chosen as the feedstock mineral, due to its abundance and availability. However, the relatively low reactivity of serpentine has warranted research into physical and chemical treatments that have been shown to greatly increase its reactivity. The use of sulfuric acid as an accelerating medium for the removal of magnesium from serpentine has recently been investigated. In addition to the challenges presented by the dissolution of serpentine, another challenge is the subsequent carbonation of the magnesium ions. A stable hydration sphere for the magnesium ion reduces the carbonation kinetics by obstructing the formation of the carbonation products. Accordingly, this research has evaluated the solubility of carbon dioxide in aqueous solution, the interaction between the dissociation products of carbon dioxide, and the carbonation potential of the magnesium ion.
Date: March 25, 2006
Creator: Alexander, George; Maroto-Valer, M. Mercedes; Aksoy, Parvana & Schobert, Harold
Object Type: Report
System: The UNT Digital Library
Timpson & Tenaha News (Timpson, Tex.), Vol. 21, No. 9, Ed. 1 Thursday, March 2, 2006 (open access)

Timpson & Tenaha News (Timpson, Tex.), Vol. 21, No. 9, Ed. 1 Thursday, March 2, 2006

Weekly newspaper from Timpson, Texas that includes local, state, and national news along with advertising.
Date: March 2, 2006
Creator: Alexander, Nancy
Object Type: Newspaper
System: The Portal to Texas History
Timpson & Tenaha News (Timpson, Tex.), Vol. 21, No. 10, Ed. 1 Thursday, March 9, 2006 (open access)

Timpson & Tenaha News (Timpson, Tex.), Vol. 21, No. 10, Ed. 1 Thursday, March 9, 2006

Weekly newspaper from Timpson, Texas that includes local, state, and national news along with advertising.
Date: March 9, 2006
Creator: Alexander, Nancy
Object Type: Newspaper
System: The Portal to Texas History
Timpson & Tenaha News (Timpson, Tex.), Vol. 21, No. 11, Ed. 1 Thursday, March 16, 2006 (open access)

Timpson & Tenaha News (Timpson, Tex.), Vol. 21, No. 11, Ed. 1 Thursday, March 16, 2006

Weekly newspaper from Timpson, Texas that includes local, state, and national news along with advertising.
Date: March 16, 2006
Creator: Alexander, Nancy
Object Type: Newspaper
System: The Portal to Texas History
Timpson & Tenaha News (Timpson, Tex.), Vol. 21, No. 12, Ed. 1 Thursday, March 23, 2006 (open access)

Timpson & Tenaha News (Timpson, Tex.), Vol. 21, No. 12, Ed. 1 Thursday, March 23, 2006

Weekly newspaper from Timpson, Texas that includes local, state, and national news along with advertising.
Date: March 23, 2006
Creator: Alexander, Nancy
Object Type: Newspaper
System: The Portal to Texas History
Timpson & Tenaha News (Timpson, Tex.), Vol. 21, No. 13, Ed. 1 Thursday, March 30, 2006 (open access)

Timpson & Tenaha News (Timpson, Tex.), Vol. 21, No. 13, Ed. 1 Thursday, March 30, 2006

Weekly newspaper from Timpson, Texas that includes local, state, and national news along with advertising.
Date: March 30, 2006
Creator: Alexander, Nancy
Object Type: Newspaper
System: The Portal to Texas History
Smart Screening System (S3) In Taconite Processing (open access)

Smart Screening System (S3) In Taconite Processing

The conventional screening machines used in processing plants have had undesirable high noise and vibration levels. They also have had unsatisfactorily low screening efficiency, high energy consumption, high maintenance cost, low productivity, and poor worker safety. These conventional vibrating machines have been used in almost every processing plant. Most of the current material separation technology uses heavy and inefficient electric motors with an unbalanced rotating mass to generate the shaking. In addition to being excessively noisy, inefficient, and high-maintenance, these vibrating machines are often the bottleneck in the entire process. Furthermore, these motors, along with the vibrating machines and supporting structure, shake other machines and structures in the vicinity. The latter increases maintenance costs while reducing worker health and safety. The conventional vibrating fine screens at taconite processing plants have had the same problems as those listed above. This has resulted in lower screening efficiency, higher energy and maintenance cost, and lower productivity and workers safety concerns. The focus of this work is on the design of a high performance screening machine suitable for taconite processing plants. SmartScreens{trademark} technology uses miniaturized motors, based on smart materials, to generate the shaking. The underlying technologies are Energy Flow Control{trademark} and Vibration Control …
Date: March 1, 2006
Creator: Allaei, Daryoush; Wartman, Ryan; Tarnowski, David & Mohammed, Asim Syed
Object Type: Report
System: The UNT Digital Library