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Search for Lepton Flavor Violation in the Decay tau -> electron gamma
A search for the non-conservation of lepton flavor in the decay {tau}{sup {+-}} {yields} e{sup {+-}}{gamma} has been performed with 2.07 x 10{sup 8} e{sup +}e{sup -} {yields} {tau}{sup +}{tau}{sup -} events collected by the BABAR detector at the PEP-II storage ring at a center-of-mass energy near 10.58 GeV. They find no evidence for a signal and set an upper limit on the branching ratio of {Beta}({tau}{sup {+-}} {yields} e{sup {+-}}{gamma}) < 1.1 x 10{sup -7} at 90% confidence level.
Date:
August 26, 2005
Creator:
Aubert, B.; Barate, R.; Boutigny, D.; Couderc, F.; Karyotakis, Y.; Lees, J. P. et al.
Object Type:
Article
System:
The UNT Digital Library
Search for W-exchange decays B0 -> Ds(*)- Ds(*)+
The authors report a search for the decays B{sup 0} {yields} D{sub s}{sup -}D{sub s}{sup +}, B{sup 0} {yields} D*{sub s}{sup -}D{sub s}{sup +} and B{sup 0} {yields} D*{sub s}{sup -}D*{sub s}{sup +} in a sample of 232 million {Upsilon}(4S) decays to B{bar B} pairs collected with the BABAR detector at the PEP-II asymmetric-energy e{sup +}e{sup -} storage ring. They find no significant signal and set upper bounds for the branching fractions: {Beta}(B{sup 0} {yields} D{sub s}{sup -}D{sub s}{sup +}) < 1.0 x 10{sup -4}, {Beta}(B{sup 0} {yields} D*{sub s}{sup -} D{sub s}{sup +}) < 1.3 x 10{sup -4} and {Beta}(B{sup 0} {yields} D*{sub s}{sup -} D*{sub s}{sup +}) < 2.4 x 10{sup -4} at 90% confidence level.
Date:
October 26, 2005
Creator:
Aubert, B.; Barate, R.; Boutigny, D.; Couderc, F.; Karyotakis, Y.; Lees, J. P. et al.
Object Type:
Article
System:
The UNT Digital Library
Dalitz Plot Analysis of Ds+->pi+pi-pi+
A Dalitz plot analysis of {approx} 13, 000 D{sub s}{sup +} decays to {pi}{sup +}{pi}{sup +}{pi}{sup -} has been performed. A 384 fb{sup -1} data sample, recorded by the BABAR detector at the PEP-II asymmetric-energy e{sup +}e{sup -} storage ring running at center of mass energies near 10.6 GeV, is used. Amplitudes and phases of the intermediate resonances which contribute to this final state are measured. A high precision measurement of the ratio: {Beta}(D{sub s}{sup +} {yields} {pi}{sup +}{pi}{sup +}{pi}{sup -})/{Beta}(D{sub s}{sup +} {yields} K{sup +}K{sup -}{pi}{sup +}) = 0.199 {+-} 0.004 {+-} 0.006 is performed. Using a model independent partial wave analysis the amplitude and phase of the S-wave have been measured.
Date:
January 26, 2009
Creator:
Aubert, B.; Bona, M.; Karyotakis, Y.; Lees, J. P.; Poireau, V.; Prencipe, E. et al.
Object Type:
Article
System:
The UNT Digital Library
Observation of e^+e^- to \rho^+\rho^- near \sqrt{s}=10.58\gev
The authors report the first observation of e{sup +}e{sup -} {yields} {rho}{sup +}{rho}{sup -}, in a data sample of 379 fb{sup -1} collected with the BABAR detector at the PEP-II e{sup +}e{sup -} storage ring at center-of-mass energies near {radical}s = 10.58 GeV. The authors measure a cross section of {sigma}(e{sup +}e{sup -} {yields} {rho}{sup +}{rho}{sup -}) = 19.5 {+-} 1.6(stat) {+-} 3.2(syst) fb. Assuming production through single-photon annihilation, there are three independent helicity amplitudes. They measure the ratios of their squared moduli to be |F{sub 00}|{sup 2} : |F{sub 10}|{sup 2} : |F{sub 11}|{sup 2} = 0.51 {+-} 0.14(stat) {+-} 0.07(syst) : 0.10 {+-} 0.04(stat) {+-} 0.01(syst) : 0.04 {+-} 0.03(stat) {+-} 0.01(syst). The |F{sub 00}|{sup 2} result is inconsistent with the prediction of 1.0 made by QCD models with a significance of 3.1 standard deviations including systematic uncertainties.
Date:
June 26, 2008
Creator:
Aubert, B.; Bona, M.; Karyotakis, Y.; Lees, J. P.; Poireau, V.; Prencipe, E. et al.
Object Type:
Article
System:
The UNT Digital Library
HADES User's Manual
HADES is a computer code that simulates transmission radiography through a mesh and/or solid bodies. This code is a successor to an old code called XRAY. HADES is designed to be backward compatible with XRAY (i.e. it will accept and correctly parse XRAY input decks), but HADES has many more features that greatly enhance its versatility and its simulation of experimental effects. HADES can simulate X-Ray radiography, neutron radiography or GeV proton radiography using ray-tracing techniques. A short article has been published which discusses HADES' capabilities. HADES also has some capability for simulating pinhole imaging and backlight imaging. The best way to obtain HADES is to ask one of the authors for a copy. This manual covers all features in version 2.5.0 of HADES.
Date:
December 26, 2002
Creator:
Aufderheide, M B; Slone, D M & Schach Von Wittenau, A E
Object Type:
Text
System:
The UNT Digital Library
Simulation of Phase Effects in Imaging for Mesoscale NDE
High energy density experiments, such as those planned at the National Ignition Facility (NIF), use mesoscale targets with the goals of studying high energy density physics, inertial confinement fusion, and the support of national security needs. Mesoscale targets are typically several millimeters in size and have complex micrometer-sized structures composed of high-density metals and low-density foams and ices. These targets are designed with exacting tolerances that are difficult to achieve at present. Deviation from these tolerances can result in compromise of experimental goals and thus it is necessary to determine as-built properties of these targets using NDE techniques. Radiography and computed tomography are being used to investigate these targets, but the mix between phase and absorption information is difficult to separate, making interpretation of results difficult. We have recently improved the HADES radiographic simulation code to include phase in simulations, as an aid for doing NDE on mesoscale targets. In this paper we report on how we extended HADES to incorporate phase effects, and compare simulations with a variety of experimental test results.
Date:
August 26, 2004
Creator:
Aufderheide, M. B., III; Barty, A. & Martz, H. E., Jr.
Object Type:
Article
System:
The UNT Digital Library
LANDFILL OPERATION FOR CARBON SEQUESTRATION AND MAXIMUM METHANE EMISSION CONTROL
Controlled landfilling is an approach to manage solid waste landfills, so as to rapidly complete methane generation, while maximizing gas capture and minimizing the usual emissions of methane to the atmosphere. With controlled landfilling, methane generation is accelerated to more rapid and earlier completion to full potential by improving conditions (principally moisture, but also temperature) to optimize biological processes occurring within the landfill. Gas is contained through use of surface membrane cover. Gas is captured via porous layers, under the cover, operated at slight vacuum. A field demonstration project has been ongoing under NETL sponsorship for the past several years near Davis, CA. Results have been extremely encouraging. Two major benefits of the technology are reduction of landfill methane emissions to minuscule levels, and the recovery of greater amounts of landfill methane energy in much shorter times, more predictably, than with conventional landfill practice. With the large amount of US landfill methane generated, and greenhouse potency of methane, better landfill methane control can play a substantial role both in reduction of US greenhouse gas emissions and in US renewable energy. The work described in this report, to demonstrate and advance this technology, has used two demonstration-scale cells of size (8000 …
Date:
February 26, 2000
Creator:
Augenstein, Don; Yazdani, Ramin; Moore, Rick; Byars, Michelle; Kieffer, Jeff; Barlaz, Professor Morton et al.
Object Type:
Report
System:
The UNT Digital Library
Next Generation of Latin-American Church Leaders
Lecture given Saturday, June 26, 2004 at Abilene Christian University: "God has prepared a vast spiritual harvest among the growing Hispanic population in the U. S. Explore the challenges of training able workers for this field."
Date:
June 26, 2004
Creator:
Austin, Stephen
Object Type:
Sound
System:
The Portal to Texas History
Implementation of DOE/NFDI D&D Cost Estimating Tool (POWERtool) for Initiative Facilities at the Savannah River Site
The Savannah River Site (SRS) has embarked on an aggressive D&D program to reduce the footprint of excess facilities. Key to the success of this effort is the preparation of accurate cost estimates for decommissioning. SRS traditionally uses ''top-down'' rough order-of-magnitude (ROM) estimating for decommissioning cost estimates. A second cost estimating method (POWERtool) using a ''bottoms-up'' approach has been applied to many of the SRS excess facilities in the T and D-area. This paper describes the use of both estimating methods and compares the estimated costs to actual costs of 5 facilities that were decommissioned in 2002.
Date:
February 26, 2003
Creator:
Austin, W. E.; WSRC; Baker, S. B. III, Cutshall, C. M. & Crouse, J. L.
Object Type:
Article
System:
The UNT Digital Library
Development of Monte Carlo Methods for Investigating Migration of Radionuclides in Contaminated Environments
This paper presents the results of an ongoing research and development project conducted by Russian institutions in Moscow and Snezhinsk, supported by the International Science and Technology Center (ISTC), in collaboration with the University of Oklahoma. The joint study focuses on developing and applying analytical tools to effectively characterize contaminant transport and assess risks associated with migration of radionuclides and heavy metals in the water column and sediments of large reservoirs or lakes. The analysis focuses on the development and evaluation of theoretical-computational models that describe the distribution of radioactive wastewater within a reservoir and characterize the associated radiation field as well as estimate doses received from radiation exposure. The analysis focuses on the development and evaluation of Monte Carlo-based, theoretical-computational methods that are applied to increase the precision of results and to reduce computing time for estimating the characteristics the radiation field emitted from the contaminated wastewater layer. The calculated migration of radionuclides is used to estimate distributions of radiation doses that could be received by an exposed population based on exposure to radionuclides from specified volumes of discrete aqueous sources. The calculated dose distributions can be used to support near-term and long-term decisions about priorities for environmental remediation …
Date:
February 26, 2002
Creator:
Avrorin, E. N.; Tsvetokhin, A. G.; Xenofontov, A. I.; Kourbatova, E. I. & Regens, J. L.
Object Type:
Article
System:
The UNT Digital Library
Hough Transform Based Corner Detection for Laser Beam Positioning
In laser beam alignment in addition to detecting position, one must also determine the rotation of the beam. This is essential when a commissioning new laser beam for National Ignition Facility located at the Lawrence Livermore National Laboratory. When the beam is square, the positions of the corners with respect to one another provides an estimate of the rotation of the beam. This work demonstrates corner detection in the presence or absence of a second order non-uniform illumination caused by a spatial mask. The Hough transform coupled with illumination dependent pre-processing is used to determine the corner points. We show examples from simulated and real NIF images.
Date:
July 26, 2005
Creator:
Awwal, A. S.
Object Type:
Article
System:
The UNT Digital Library
Composite Amplitude Modulated Phase Only Filter Based Detection and Tracking of the Back-Reflection of KDP Images
An algorithm for determining the position of the KDP back-reflection image was developed. It was compared to a centroid-based algorithm. While the algorithm based on centroiding exhibited a radial standard deviation of 9 pixels, the newly proposed algorithm based on classical matched filtering (CMF) and a Gaussian fit to correlation peak provided a radial standard deviation of less than 1 pixel. The speed of the peak detection was improved from an average of 5.5 seconds for Gaussian fit to 0.022 seconds by using a polynomial fit. The performance was enhanced even further by utilizing a composite amplitude modulated phase only filter; producing a radial standard deviation of 0.27 pixels. The proposed technique was evaluated on 900+ images with varying degrees of noise and image amplitude as well as real National Ignition Facility (NIF) images.
Date:
August 26, 2004
Creator:
Awwal, A. S.; McClay, W. A.; Ferguson, S. W.; Candy, J. V.; Salmon, J. T. & Wegner, P. J.
Object Type:
Article
System:
The UNT Digital Library
Non-Destructive Evaluation of Thermal Spray Coating Interface Quality by Eddy Current Method
Thermal spray coating is usually applied through directing molten or softened particles at very high velocities onto a substrate. An eddy current non-destructive inspection technique is presented here for thermal spray coating interface quality characterization. Several high-velocity-oxy-fuel (HVOF) coated steel plates were produced with different surface preparation conditions before applying the coating, e.g., grit-blasted surface, wire-brush cleaned surface, and a dirty surface. A quad-frequency eddy current probe was used to manually scan over the coating surface to evaluate the bonding quality. Experimental results show that the three surface preparation conditions can be successfully differentiated by looking into the impedance difference observed from the eddy current probe. The measurement is fairly robust and consistent. More specimens are also prepared with variations of process parameters, such as spray angle, stand-off distance, and application of corrosion protective sealant, etc. They are blindly tested to evaluate the reliability of the eddy current system. Quantitative relations between the coating bond strength and the eddy current response are also established with the support of destructive testing. This non-contact, non-destructive, easy to use technique has the potential for evaluating the coating quality immediately after its application so that any defects can be corrected immediately.
Date:
May 26, 2006
Creator:
B.Mi; Zhao, X. & Bayles, R.
Object Type:
Report
System:
The UNT Digital Library
A Precision Measurement of the Ds1 (2536)+ Meson Mass and Decay Width
The decay width and the mass of the D{sub s1}(2536){sup {+-}} have been measured via the decay channel D{sub s1}{sup {+-}} {yields} D*{sup {+-}}K{sub S}{sup 0} using 232 fb{sup -1} of data collected with the BABAR detector at the PEP-II asymmetric-energy e{sup +}e{sup -} storage ring. The result for the decay width is {Lambda}(D{sub s1}{sup {+-}}) = (1.03 {+-} 0.05 {+-} 0.12) MeV/c{sup 2}, with the first error denoting the statistical uncertainty and the second one the systematic uncertainty. For the mass, a value of m(D{sub s1}{sup {+-}}) = (2534.85 {+-} 0.02 {+-} 0.40) MeV/c{sup 2} has been obtained. The systematic error is dominated by the uncertainty on the D*{sup {+-}} mass. The mass difference between the D{sub s1}{sup {+-}} and D*{sup {+-}} has been measured to be {Delta}m = (524.85 {+-} 0.02 {+-} 0.04) MeV/c{sup 2}.
Date:
September 26, 2006
Creator:
BABAR Collaboration,
Object Type:
Article
System:
The UNT Digital Library
END FIELD EFFECTS IN BEND ONLY COOLING LATTICES.
Cooling lattices consisting only of bends (using either rotated pole faces or gradient dipoles to achieve focusing) often require large apertures and short magnets. One expects the effect of end fields to be significant in this case. In this paper we explore the effect of adding end fields to a working lattice design that originally lacked them. The paper describes the process of correcting the lattice design for the added end fields so as to maintain desirable lattice characteristics. It then compares the properties of the lattice with end fields relative to the lattice without them.
Date:
June 26, 2003
Creator:
BEERG,J. S. KIRK,H. GARREN,A.
Object Type:
Article
System:
The UNT Digital Library
DESIGN OF FFAGS BASED ON A FODO LATTICE.
An FFAG is a lattice with fixed magnetic fields that has an extremely wide energy acceptance. One particularly simple type of FFAG is based on a FODO lattice, where both quads can be combined-function bending/quadrupole magnets. The spaces between the combined-function magnets are left open for RF cavities and other hardware. This paper describes a general method for creating lattice designs for this type of lattice which gives the lattice optimal properties for an FFAG accelerator. The properties of this lattice as a function of input parameters are explored. The use of sextupoles to improve lattice properties is also explored.
Date:
June 26, 2003
Creator:
BERG,J. S. JOHNSTONE,C.
Object Type:
Article
System:
The UNT Digital Library
FFAGS FOR MUON ACCELERATION.
Due to their finite lifetime, muons must be accelerated very rapidly. It is challenging to make the magnets ramp fast enough to accelerate in a synchrotron, and accelerating in a linac is very expensive. One can use a recirculating accelerator (like CEBAF), but one needs a different arc for each turn, and this limits the number of turns one can use to accelerate, and therefore requires significant amounts of RF to achieve the desired energy gain. An alternative method for muon acceleration is using a fixed field alternating gradient (FFAG) accelerator. Such an accelerator has a very large energy acceptance (a factor of two or three), allowing one to use the same arc with a magnetic field that is constant over time. Thus, one can in principle make as many turns as one can tolerate due to muon decay, therefore reducing the RF cost without increasing the arc cost. This paper reviews the current status of research into the design of FFAGs for muon acceleration. Several current designs are described and compared. General design considerations are also discussed.
Date:
June 26, 2003
Creator:
BERG,J. S. KAHN,S. PALMER,R. TRBOJEVIC,D. JOHNSTONE,C. KEIL,Y. OGITSU,T. OHMORI,C. SESSLER,A. KOSCIELNIAK,S.
Object Type:
Article
System:
The UNT Digital Library
LINEAR DESIGN OF COMBINED FUNCTION IONIZATION COOLING LATTICES.
Ionization cooling lattices simultaneously require small beta-functions at the absorber and large energy acceptances to be effective. Simultaneously achieving these goals as well as having a good dynamic aperture requires that the lattice be relatively compact. If one wishes to avoid solenoids, one choice for creating such a lattice is to use combined-function magnets. These magnets can simultaneously focus in both planes, allowing one to achieve a low beta in both planes with a minimum number of magnets. In this paper we explore the design of lattices which contain only combined-function bending magnets using a thin-lens approximation, showing how to optimally achieve the requirements for muon cooling.
Date:
June 26, 2003
Creator:
BERG,J. S. KIRK,H. GARREN,A.
Object Type:
Article
System:
The UNT Digital Library
ELECTRICAL SAFETY IMPROVEMENT PROJECT A COMPLEX WIDE TEAMING INITIATIVE
This paper describes the results of a year-long project, sponsored by the Energy Facility Contractors Group (EFCOG) and designed to improve overall electrical safety performance throughout Department of Energy (DOE)-owned sites and laboratories. As evidenced by focused metrics, the Project was successful primarily due to the joint commitment of contractor and DOE electrical safety experts, as well as significant support from DOE and contractor senior management. The effort was managed by an assigned project manager, using classical project-management principles that included execution of key deliverables and regular status reports to the Project sponsor. At the conclusion of the Project, the DOE not only realized measurable improvement in the safety of their workers, but also had access to valuable resources that will enable them to do the following: evaluate and improve electrical safety programs; analyze and trend electrical safety events; increase electrical safety awareness for both electrical and non-electrical workers; and participate in ongoing processes dedicated to continued improvement.
Date:
November 26, 2007
Creator:
BJ, GRAY
Object Type:
Article
System:
The UNT Digital Library
PFP Commercial Grade Food Pack Cans for Plutonium Handling and Storage Critical Characteristics
This document specifies the critical characteristics for containers procured for Plutonium Finishing Plant's (PFP's) Vault Operations system as required by HNF-PRO-268 and HNF-PRO-1819. These are the minimum specifications that the equipment must meet in order to perform its safety function.
Date:
October 26, 2000
Creator:
BONADIE, E.P.
Object Type:
Report
System:
The UNT Digital Library
Overview of energy storage applications
Sandia National Laboratories has been studying Energy Storage Systems since the late 1970s. Sandia started by applying their defense program battery experience to larger stationary systems, eventually joining in the formation of the Utility Battery Group which has since evolved into the Energy Storage Association. Sandia's role, as a Department of Energy funded program is to look ahead at emerging technologies, perform early R and D and identify applications for Energy Storage Systems that offer significant benefit to the nation's electricity providers and users. In order to identify applications of energy storage, a two-phase Opportunities Analysis was conceptualized in FY94. Phase 1 of the project was completed and published in 1995 (SAND94-2605). Phase 2 of the project is an extension of Phase 1 to reexamine the identified applications in the dynamic environment of today. In a preliminary assessment of national benefits, SNL estimated that generation and transmission applications of storage could represent $17.2B in national benefits. In Phase 1 of the Opportunities Analysis, the T and D benefits were found to be significantly higher than previous estimates Phase 2 of the study, which began in late 1998, includes a refinement of the technical and economic understanding of the role of …
Date:
April 26, 2000
Creator:
BOYES,JOHN D.
Object Type:
Article
System:
The UNT Digital Library
Technologies for energy storage flywheels and super conducting magnetic energy storage
A flywheel is an electromechanical storage system in which energy is stored in the kinetic energy of a rotating mass. Flywheel systems under development include those with steel flywheel rotors and resin/glass or resin/carbon-fiber composite rotors. The mechanics of energy storage in a flywheel system are common to both steel- and composite-rotor flywheels. In both systems, the momentum of the rotating rotor stores energy. The rotor contains a motor/generator that converts energy between electrical and mechanical forms. In both types of systems, the rotor operates in a vacuum and spins on bearings to reduce friction and increase efficiency. Steel-rotor systems rely mostly on the mass of the rotor to store energy while composite flywheels rely mostly on speed. During charging, an electric current flows through the motor increasing the speed of the flywheel. During discharge, the generator produces current flow out of the system slowing the wheel down. The basic characteristics of a Flywheel system are shown. Steel flywheel systems are currently being marketed in the US and Germany and can be connected in parallel to provide greater power if required. Sizes range from 40kW to 1.6MW for times of 5--120 seconds. At this time sales are limited but growing. …
Date:
April 26, 2000
Creator:
BOYES,JOHN D.
Object Type:
Article
System:
The UNT Digital Library
NUCLEAR INFORMATION SERVICES AT THE NATIONAL NUCLEAR DATA CENTER.
The National Nuclear Data Center has provided remote access to its databases and other resources since 1986. This year we have completed the modernization of our databases and Web site. Resources available from our Web site will be summarized and some of the major improvements described in more detail.
Date:
September 26, 2004
Creator:
BURROWS,T. W. & DUNFORD,C. L.
Object Type:
Article
System:
The UNT Digital Library
DETAILED ANALYSIS OF THE MOST PROMISING ALTERNATIVES TO USING GRANULAR ACTIVATED CARBON TO TREAT 200-ZP-1 GROUNDWATER AND 200-PW-1 SOIL VAPOR
This document presents a detailed evaluation of selected alternative treatment options to granular activated carbon (GAC) for removing carbon tetrachloride generated from the groundwater pump-and-treat system at the 200-ZP-I Operable Unit (OU) in the 200 West Area of the Hanford Site. This evaluation of alternative treatment options to GAC is also applicable to the vadose zone soil vapor extraction (SVE) system at the 200-PW-l OU, which is also located in the Hanford Site's 200 West Area.
Date:
November 26, 2007
Creator:
BYRNES ME, KALMAR JA
Object Type:
Report
System:
The UNT Digital Library