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B0 Meson Decays to Rho0 K*0, f0 K*0, and Rho- K*+, Including Higher K* Resonances (open access)

B0 Meson Decays to Rho0 K*0, f0 K*0, and Rho- K*+, Including Higher K* Resonances

None
Date: October 25, 2013
Creator: Lees, J. P.; Poireau, V.; Tisserand, V.; Garra Tico, J.; Grauges, E.; Martinelli, M. et al.
System: The UNT Digital Library
Bacterial Community Profiling of Milk Samples as a Means to Understand Culture-Negative Bovine Clinical Mastitis (open access)

Bacterial Community Profiling of Milk Samples as a Means to Understand Culture-Negative Bovine Clinical Mastitis

Article discussing a study that was conducted to understand the basis of a bacterial infection that is common among dairy cows.
Date: April 25, 2013
Creator: Kuehn, Joanna S.; Gorden, Patrick J.; Munro, Daniel; Rong, Ruichen; Dong, Qunfeng; Plummer, Paul J. et al.
System: The UNT Digital Library
Battery testing at Argonne National Laboratory (open access)

Battery testing at Argonne National Laboratory

Argonne National Laboratory`s Analysis & Diagnostic Laboratory (ADL) tests advanced batteries under simulated electric and hybrid vehicle operating conditions. The ADL facilities also include a post-test analysis laboratory to determine, in a protected atmosphere if needed, component compositional changes and failure mechanisms. The ADL provides a common basis for battery performance characterization and life evaluations with unbiased application of tests and analyses. The battery evaluations and post-test examinations help identify factors that limit system performance and life, and the most-promising R&D approaches for overcoming these limitations. Since 1991, performance characterizations and/or life evaluations have been conducted on eight battery technologies (Na/S, Li/S, Zn/Br, Ni/MH, Ni/Zn, Ni/Cd, Ni/Fe, and lead-acid). These evaluations were performed for the Department of Energy`s. Office of Transportation Technologies, Electric and Hybrid Propulsion Division (DOE/OTT/EHP), and Electric Power Research Institute (EPRI) Transportation Program. The results obtained are discussed.
Date: March 25, 1993
Creator: DeLuca, W. H.; Gillie, K. R.; Kulaga, J. E.; Smaga, J. A.; Tummillo, A. F. & Webster, C. E.
System: The UNT Digital Library
Battery testing at Argonne National Laboratory (open access)

Battery testing at Argonne National Laboratory

Argonne National Laboratory's Analysis Diagnostic Laboratory (ADL) tests advanced batteries under simulated electric and hybrid vehicle operating conditions. The ADL facilities also include a post-test analysis laboratory to determine, in a protected atmosphere if needed, component compositional changes and failure mechanisms. The ADL provides a common basis for battery performance characterization and life evaluations with unbiased application of tests and analyses. The battery evaluations and post-test examinations help identify factors that limit system performance and life, and the most-promising R D approaches for overcoming these limitations. Since 1991, performance characterizations and/or life evaluations have been conducted on eight battery technologies (Na/S, Li/S, Zn/Br, Ni/MH, Ni/Zn, Ni/Cd, Ni/Fe, and lead-acid). These evaluations were performed for the Department of Energy's. Office of Transportation Technologies, Electric and Hybrid Propulsion Division (DOE/OTT/EHP), and Electric Power Research Institute (EPRI) Transportation Program. The results obtained are discussed.
Date: March 25, 1993
Creator: DeLuca, W. H.; Gillie, K. R.; Kulaga, J. E.; Smaga, J. A.; Tummillo, A. F. & Webster, C. E.
System: The UNT Digital Library
Beam-Based Alignment, Tuning and Beam Dynamics Studies for the ATF2 Extraction Line and Final Focus System (open access)

Beam-Based Alignment, Tuning and Beam Dynamics Studies for the ATF2 Extraction Line and Final Focus System

Using a new extraction line currently under construction, the ATF2 experiment plans to test the novel compact final focus optics design with local chromaticity correction intended for use in future linear colliders. With a 1.3 GeV design beam of 30nm normalized vertical emittance extracted from the ATF damping ring, the primary goal is to achieve a vertical spot-size at the IP waist of 37nm. We discuss our planned strategy for tuning the ATF2 beam to meet the primary goal. Simulation studies have been performed to asses the effectiveness of the strategy, including 'static' (installation) errors and dynamical effects (ground-motion, mechanical vibration, ring extraction jitter etc.). We have simulated all steps in the tuning procedure, from initial orbit establishment to final IP spot-size tuning. Through a Monte Carlo study of 100's of simulation seeds we find we can achieve a spot-size within {approx}10% of the design optics value in at least 75% of cases. We also ran a simulation to study the long-term performance with the use of beam-based feedbacks.
Date: July 25, 2008
Creator: White, Glen R.; /LAL, Orsay /SLAC; Molloy, S.; Woodley, M. & /SLAC
System: The UNT Digital Library
Beam-Based Sextupole Polarity Verification in the RHIC (open access)

Beam-Based Sextupole Polarity Verification in the RHIC

This article presents a beam-based method to check RHIC arc sextupole polarities using local horizontal orbit three-bumps at injection energy. We use 11 bumps in each arc, each covering two SFs (focusing sextupoles) and one SD (defocusing sextupole). If there are no wrong sextupole polarities, the tune shifts from bump to bump and the tune shift patterns from arc to arc should be similar. Wrong sextupole polarities can be easily identified from mismatched signs or amplitudes of tune shifts from bump to bump and/or from arc to arc. Tune shifts in both planes during this study were tracked with a high-resolution base-band tunemeter (BBQ) system. This method was successfully used to the sextupole polarity check in RHIC Blue and Yellow rings in the RHIC 2006 and 2007 runs.
Date: June 25, 2007
Creator: Luo, Y.; Satogata, T.; Cameron, P.; Dellapenna, A. & Trbojevic, D.
System: The UNT Digital Library
Beam dynamics limits for low-energy RHIC operation (open access)

Beam dynamics limits for low-energy RHIC operation

There is a strong interest in low-energy RHIC operations in the single-beam total energy range of 2.5-25 GeV/nucleon [1-3]. Collisions in this energy range, much of which is below nominal RHIC injection energy, will help to answer one of the key questions in the field of QCD about the existence and location of a critical point on the QCD phase diagram [4]. There have been several short test runs during 2006-2008 RHIC operations to evaluate RHIC operational challenges at these low energies [5]. Beam lifetimes observed during the test runs were limited by machine nonlinearities. This performance limit can be improved with sufficient machine tuning. The next luminosity limitation comes from transverse and longitudinal Intra-beam Scattering (IBS), and ultimately from the space-charge limit. Here we summarize dynamic effects limiting beam lifetime and possible improvement with electron cooling.
Date: August 25, 2008
Creator: Fedotov, A. V.; Ben-Zvi, Ilan; Chang, X.; Kayran, D.; Litvinenko, V. N.; Pozdeyev, E. et al.
System: The UNT Digital Library
Beam dynamics studies in a high-brightness photo-injector (open access)

Beam dynamics studies in a high-brightness photo-injector

A high-brightness photo-injector has been developed at Fermilab in collaboration with the TTF project at DESY. Two systems have been commissioned, one at DESY and one at Fermilab. The injector [1] consists of a 1.625-cell cavity RF gun, a superconducting niobium cavity (both 1.3 GHz), and a magnetic chicane. The gun is designed for an electric field of up to 50 MV/m on the cathode. Emittance compensation solenoids surround the gun to correct the linear space charge emittance growth. A high quantum efficiency Cs{sub 2}Te photocathode located in the first half-cell produces electrons when illuminated by 263 nm wavelength light (fourth harmonic of the Nd:YLF laser). The laser [2] was designed to produce a train of up to 800 equal amplitude, 10 {micro}J UV pulses spaced by 1 {micro}s at 1 Hz repetition rate. The laser pulse length is adjustable between 1 and 20 ps FWHM. The superconducting cavity is a 9-cell Nb structure fabricated by industry for TTF. It was tested with RF at DESY before being sent to Fermilab. At present, the cavity is operated at {approx}11 MeV/m. Beam measurements with the injector at Fermilab are in progress. Preliminary results for emittance and bunch length will be discussed …
Date: October 25, 1999
Creator: Carneiro, Jean-Paul
System: The UNT Digital Library
Beam tests of ionization chambers for the NuMI neutrino beam (open access)

Beam tests of ionization chambers for the NuMI neutrino beam

We have conducted tests at the Fermilab Booster of ionization chambers to be used as monitors of the NuMI neutrino beamline. The chambers were exposed to proton fluxes of up to 10{sup 12} particles/cm{sup 2}/1.56 {micro}s. We studied space charge effects which can reduce signal collection from the chambers at large charged particle beam intensities.
Date: September 25, 2003
Creator: al., Robert M. Zwaska et
System: The UNT Digital Library
Beryllium Sampling and Analysis Within the DOE Complex and Opportunities for Standardization (open access)

Beryllium Sampling and Analysis Within the DOE Complex and Opportunities for Standardization

Since the U. S. Department of Energy (DOE) published the DOE Beryllium Rule (10 CFR 850) in 1999, DOE sites have been required to measure beryllium on air filters and wipes for worker protection and for release of materials from beryllium-controlled areas. Measurements in the nanogram range on a filter or wipe are typically required. Industrial hygiene laboratories have applied methods from various analytical compendia, and a number of issues have emerged with sampling and analysis practices. As a result, a committee of analytical chemists, industrial hygienists, and laboratory managers was formed in November 2003 to address the issues. The committee developed a baseline questionnaire and distributed it to DOE sites and other agencies in the U.S. and U.K. The results of the questionnaire are presented in this paper. These results confirmed that a wide variety of practices were in use in the areas of sampling, sample preparation, and analysis. Additionally, although these laboratories are generally accredited by the American Industrial Hygiene Association (AIHA), there are inconsistencies in performance among accredited labs. As a result, there are significant opportunities for development of standard methods that could improve consistency. The current availabilities and needs for standard methods are further discussed in …
Date: January 25, 2005
Creator: BRISSON, MICHAEL
System: The UNT Digital Library
Best Angle to Orient Two Intersecting Lines (open access)

Best Angle to Orient Two Intersecting Lines

Fiducials in the form of intersecting straight lines are used to align the target in the final target chamber of the National Ignition Facility of Lawrence Livermore National Laboratory. One of the techniques used to locate these lines is the Hough transform. When two lines intersect at a 90 degree angle, it is tempting to orient the lines to horizontal and vertical directions. There are other possible angles at which the lines may be oriented. One question that arises while designing the fiducials is whether there is a preferred angle or range of angles that leads to higher accuracy. This work attempts to answer this question through detailed computer simulation.
Date: July 25, 2006
Creator: Awwal, A. S.; Ferguson, S. W. & Shull, P. B.
System: The UNT Digital Library
Billion-atom Synchronous Parallel Kinetic Monte Carlo Simulations of Critical 3D Ising Systems (open access)

Billion-atom Synchronous Parallel Kinetic Monte Carlo Simulations of Critical 3D Ising Systems

None
Date: May 25, 2010
Creator: Martinez, E.; Monasterio, P. R. & Marian, J.
System: The UNT Digital Library
Billion particle linac simulations for future light sources (open access)

Billion particle linac simulations for future light sources

In this paper we report on multi-physics, multi-billion macroparticle simulation of beam transport in a free electron laser (FEL) linac for future light source applications. The simulation includes a self-consistent calculation of 3D space-charge effects, short-range geometry wakefields, longitudinal coherent synchrotron radiation (CSR) wakefields, and detailed modeling of RF acceleration and focusing. We discuss the need for and the challenges associated with such large-scale simulation. Applications to the study of the microbunching instability in an FEL linac are also presented.
Date: September 25, 2008
Creator: Ryne, R. D.; Venturini, M.; Zholents, A. A. & Qiang, J.
System: The UNT Digital Library
Binary pseudo-random grating as a standard test surface formeasurement of modulation transfer function of interferometricmicroscopes (open access)

Binary pseudo-random grating as a standard test surface formeasurement of modulation transfer function of interferometricmicroscopes

The task of designing high performance X-ray optical systemsrequires the development of sophisticated X-ray scattering calculationsbased on rigorous information about the optics. One of the mostinsightful approaches to these calculations is based on the powerspectral density (PSD) distribution of the surface height. The majorproblem of measurement of a PSD distribution with an interferometricand/or atomic force microscope arises due to the unknown ModulationTransfer Function (MTF) of the instruments. The MTF characterizes theperturbation of the PSD distribution at higher spatial frequencies. Here,we describe a new method and dedicated test surfaces for calibration ofthe MTF of a microscope. The method is based on use of a speciallydesigned Binary Pseudo-random (BPR) grating. Comparison of atheoretically calculated PSD spectrum of a BPR grating with a spectrummeasured with the grating provides the desired calibration of theinstrumental MTF. The theoretical background of the method, as well asresults of experimental investigations are presented.
Date: July 25, 2007
Creator: Yashchuk, Valeriy V.; McKinney, Wayne R. & Takacs, Peter Z.
System: The UNT Digital Library
A Biocultural Dialogue between Thoreau and Taoist Thought: Rethinking Environmental Ethics, Nature, Spirituality and Place (open access)

A Biocultural Dialogue between Thoreau and Taoist Thought: Rethinking Environmental Ethics, Nature, Spirituality and Place

Article describes how a fundamental question of the 21st century centers around the role and place of humans in their environment. The authors assert that this paper aimed to discover and manifest the connection and similarities between the philosophy of Thoreau and the ancient worldview of Taoism.
Date: June 25, 2023
Creator: Thompson, Michael & Xu, Li
System: The UNT Digital Library
Biomass and Fossil Fuel Combustion Contributions to Elemental Carbon Across the San Francisco Bay Area (open access)

Biomass and Fossil Fuel Combustion Contributions to Elemental Carbon Across the San Francisco Bay Area

This article provides better understanding in how effective regulations have been/could be across the diverse Bay Area.
Date: September 25, 2018
Creator: Yoon, Subin; Fairley, David; Barrett, Tate E. & Sheesley, Rebecca J.
System: The UNT Digital Library
Black holes in supergravity: the non-BPS branch (open access)

Black holes in supergravity: the non-BPS branch

We construct extremal, spherically symmetric black hole solutions to 4D supergravity with charge assignments that preclude BPS-saturation. In particular, we determine the ground state energy as a function of charges and moduli. We find that the mass of the non-BPS black hole remains that of a marginal bound state of four basic constituents throughout the entire moduli space and that there is always a non-zero gap above the BPS bound.
Date: October 25, 2007
Creator: Gimon, Eric; Gimon, Eric G.; Larsen, Finn & Simon, Joan
System: The UNT Digital Library
The Blend Down Monitoring System Demonstration at the Paducah Gaseous Diffusion Plant (open access)

The Blend Down Monitoring System Demonstration at the Paducah Gaseous Diffusion Plant

Agreements between the governments of the US and the Russian Federation for the US purchase of low enriched uranium (LEU) derived from highly enriched uranium (HEU) from dismantled Russian nuclear weapons calls for the establishment of transparency measures to provide confidence that nuclear nonproliferation goals are being met. To meet these transparency goals, the agreements call for the installation of nonintrusive US instruments to monitor the down blending of HEU to LEU. The Blend Down Monitoring System (BDMS) has been jointly developed by the Los Alamos National Laboratory (LANL) and the Oak Ridge National Laboratory (ORNL) to continuously monitor {sup 235}U enrichments and mass flow rates at Russian blending facilities. Prior to its installation in Russian facilities, the BDMS was installed and operated in a UF{sub 6} flow loop in the Paducah Gaseous Diffusion Plant simulating flow and enrichment conditions expected in a typical down-blending facility. A Russian delegation to the US witnessed the equipment demonstration in June, 1998. To conduct the demonstration in the Paducah Gaseous Diffusion Plant (PGDP), the BDMS was required to meet stringent Nuclear Regulatory Commission licensing, safety and operational requirements. The Paducah demonstration was an important milestone in achieving the operational certification for the BDMS …
Date: July 25, 1999
Creator: Benton, J.; Close, D.; Johnson, W., Jr.; Kerr, P.; March-Leuba, J.; Mastal, E. et al.
System: The UNT Digital Library
Blood-Based Biomarkers: A blood screening test for Alzheimer's disease (open access)

Blood-Based Biomarkers: A blood screening test for Alzheimer's disease

This article describes the first-ever multiethnic referent sample that spans community-based and clinic-based populations for implementation of an Alzheimer's disease blood screen.
Date: June 25, 2016
Creator: O'Bryant, Sid E.; Edwards, Melissa; Johnson, Leigh A.; Hall, James R.; Villarreal, Alcibiades E.; Britton, Gabrielle B. et al.
System: The UNT Digital Library
A blood screening test for Alzheimer's disease (open access)

A blood screening test for Alzheimer's disease

Article describes study examining the positive and negative predictive values of an Alzheimer's disease (AD) blood test if implemented in primary care.
Date: June 25, 2016
Creator: O'Bryant, Sid E.; Edwards, Melissa; Johnson, Leigh A.; Hall, James R.; Villarreal, Alcibiades E.; Britton, Gabrielle B. et al.
System: The UNT Digital Library
Boron-Carbide Barrier Layers in Scandium-Silicon Multilayers (open access)

Boron-Carbide Barrier Layers in Scandium-Silicon Multilayers

None
Date: March 25, 2004
Creator: Jankowski, Alan Frederic; Saw, Cheng K.; Walton, Christopher C.; Hayes, Jeffrey P. & Nilsen, Joseph
System: The UNT Digital Library
Bottoms Up: How Subnational Elections Predict Parties' Decisions to Run in Presidential Elections in Europe and Latin America (open access)

Bottoms Up: How Subnational Elections Predict Parties' Decisions to Run in Presidential Elections in Europe and Latin America

This article argues that a party's presence in elections across subnational units and its subsequent performance in these elections are determining factors for whether it enters the presidential race.
Date: August 25, 2015
Creator: Spoon, Jae-Jae & Jones West, Karleen
System: The UNT Digital Library
Bounds and Estimates for Elastic Constants of Random Polycrystals of Laminates (open access)

Bounds and Estimates for Elastic Constants of Random Polycrystals of Laminates

In order to obtain formulas providing estimates for elastic constants of random polycrystals of laminates, some known rigorous bounds of Peselnick, Meister, and Watt are first simplified. Then, some new self-consistent estimates are formulated based on the resulting analytical structure of these bounds. A numerical study is made, assuming first that the internal structure (i.e., the laminated grain structure) is not known, and then that it is known. The purpose of this aspect of the study is to attempt to quantify the differences in the predictions of properties of the same system being modeled when such internal structure of the composite medium and spatial correlation information is and is not available.
Date: August 25, 2004
Creator: Berger, E. L.
System: The UNT Digital Library
Bounds on Dark Matter Interactions with Electroweak Gauge Bosons (open access)

Bounds on Dark Matter Interactions with Electroweak Gauge Bosons

None
Date: October 25, 2013
Creator: Cotta, R. C.; Hewett, J. L.; Le, M. P. & Rizzo, T. G.
System: The UNT Digital Library