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A Comparison of EPIcode and ALOHA Calculations for Pool Evaporation and Chemical Atmospheric Transport and Dispersion. (open access)

A Comparison of EPIcode and ALOHA Calculations for Pool Evaporation and Chemical Atmospheric Transport and Dispersion.

EPIcode (version 7.0) and ALOHA (version 5.2.3) are two of the designated toolbox codes identified in the Department of Energy's Implementation Plan for DNFSB Recommendation 2002-1 on Software Quality Assurance issues in the DOE Complex. Both have the capability to estimate evaporation rates from pools formed from chemical spills and to predict subsequent atmospheric transport and dispersion. This paper provides an overview of the algorithms used by EPIcode and ALOHA to calculate evaporation rates and downwind plume concentrations. The technical bases for these algorithms are briefly discussed, and differences in the EPIcode and ALOHA methodologies highlighted. In addition, sample calculations are performed using EPIcode and ALOHA for selected chemicals under various environmental conditions. Side-by-side comparisons of results from sample calculations are analyzed to illustrate the impact that the different methodologies used by EPIcode and ALOHA have on predicted evaporation rates and downwind concentrations.
Date: April 22, 2005
Creator: Andrew, VINCENT
System: The UNT Digital Library
Measurement of Low Energy e+e- Interactions at BABARwith Initial State Radiation (open access)

Measurement of Low Energy e+e- Interactions at BABARwith Initial State Radiation

The status of the analysis of e{sup +}e{sup -} annihilation using the radiative return technique at BaBar is presented. Cross sections for the processes e{sup +}e{sup -} {yields} {pi}{sup +}{pi}{sup -}{pi}{sup 0}, {pi}{sup +}{pi}{sup -}{pi}{sup +}{pi}{sup -}, {pi}{sup +}{pi}{sup -}K{sup +}K{sup -}, K{sup +}K{sup -}K{sup +}K{sup -}, 3({pi}{sup +}{pi}{sup -}), {pi}{sup 0}{pi}{sup 0}2({pi}{sup +}{pi}{sup -}), K{sup +}K{sup -}2({pi}{sup +}{pi}{sup -}) and p{bar p} are measured in the energy range from threshold up to 4.5 GeV. Studies on resonant structures involved in these processes have been performed. We present also new precise measurements of the effective proton form factor and of the ratio of the electric to magnetic proton form factor, |G{sub E}/G{sub M}|. In addition, the J/{psi} and {psi}(2S) branching fractions to all these final states have been measured.
Date: February 22, 2006
Creator: Anulli, F.
System: The UNT Digital Library
Proton Form Factors Measurements in the Time-Like Region (open access)

Proton Form Factors Measurements in the Time-Like Region

I present an overview of the measurement of the proton form factors in the time-like region. BABAR has recently measured with great accuracy the e{sup +}e{sup -} {yields} p{bar p} reaction from production threshold up to an energy of {approx} 4.5 GeV, finding evidence for a ratio of the electric to magnetic form factor greater than unity, contrary to expectation. In agreement with previous measurements, BABAR confirmed the steep rise of the magnetic form factor close to the p{bar p} mass threshold, suggesting the possible presence of an under-threshold N{bar N} vector state. These and other open questions related to the nucleon form factors both in the time-like and space-like region, wait for more data with different experimental techniques to be possibly solved.
Date: October 22, 2007
Creator: Anulli, F.
System: The UNT Digital Library
Crystallization of a member of the recFOR DNA repair pathway, RecO, with and without bound oligonucleotide (open access)

Crystallization of a member of the recFOR DNA repair pathway, RecO, with and without bound oligonucleotide

RecFOR proteins are important for DNA repair by homologous recombination in bacteria. The RecO protein from Thermus thermophilus was cloned, purified and characterized for its binding to oligonucleotides. The protein was crystallized alone and in complex with a 14-mer oligonucleotide. Both crystal forms grow under different crystallization conditions in the same space group, P3121 or P3221, with almost identical unit cell parameters. Complete data sets were collected to 2.8 Angstrom and 2.5 Angstrom for RecO alone and the RecO-oligonucleotide complex, respectively. Visual comparison of the diffraction patterns between the two crystal forms and calculation of an Rmerge of 33.9 percent on F indicate that one of the crystal forms is indeed a complex of RecO with bound oligonucleotide.
Date: January 22, 2003
Creator: Aono, Shelly; Hartsch, Thomas & Schulze-Gahmen, Ursula
System: The UNT Digital Library
Considerations of the Role of the Cathodic Region in Localized Corrosion (open access)

Considerations of the Role of the Cathodic Region in Localized Corrosion

None
Date: March 22, 2006
Creator: Argarwal, A.; Landau, U.; Payer, J.H.; Kelly, R.G.; Cui, F. & Presuel-Moreno, F.J.
System: The UNT Digital Library
Detector Noise Susceptibility Issues for the Future Generation of High Energy Physics Experiments (open access)

Detector Noise Susceptibility Issues for the Future Generation of High Energy Physics Experiments

The front-end electronics (FEE) noise characterization to electromagnetic interference and the compatibility of the different subsystems are important topics to consider for the LHC calorimeter upgrades. A new power distribution scheme based on switching power converters is under study and will define a noticeable noise source very close to the detector's FEE. Knowledge and experience with both FFE noise and electromagnetic compatibility (EMC) issues from previous detectors are important conditions to guarantee the design goals and the good functionality of the upgraded LHC detectors. This paper shows an overview of the noise susceptibility studies performed in different CMS subdetectors. The impact of different FEE topologies in the final sensitivity to electromagnetic interference of the subsystem is analyzed and design recommendations are presented to increase the EMC of the detectors to the future challenging power distribution topologies.
Date: November 22, 2011
Creator: Arteche, F.; Esteban, C.; Iglesias, M.; Rivetta, C. & Arcega, F. J.
System: The UNT Digital Library
Equation-of-State Measurements with Z-Pinch Sources (open access)

Equation-of-State Measurements with Z-Pinch Sources

Validation of material models in a variety of scientific and technological applications requires accurate data regarding the high-pressure thermodynamic and mechanical properties. Traditional laboratory techniques for striking these measurements involve light gas guns to generate the required thermodynamic states, and the use of high-resolution time-resolved diagnostics to measure the desired material properties. EOS and constitutive material properties of importance to modeling needs include high-pressure Hugoniot curves and off-Hugoniot properties, such as. material strength and isentropic compression and decompression [1]. Conventional light gas guns are limited to impact pressures of about 7 Mbar in high-impedance materials. Pulsed radiation sources, such as high-intensity lasers, and pulsed power techniques significantly extend the accessible pressures and are becoming accepted methods for meeting the needs of material models in regimes inaccessible by gas guns. A present limitation of these new approaches is that samples must necessarily be small, typically a few tens of microns in thickness, which severely limits the accuracy of EOS measurements that can be made and also the ability to perform a variety of off-Hugoniot measurements. However, recent advances in z-pinch techniques for high-pressure material response studies provide potential opportunities for achieving accuracies comparable with gas guns because of the significantly larger …
Date: July 22, 1999
Creator: Asay, J. R.; Hall, C.; Bailey, J. E.; Knudson, M. D.; Holland, K. G.; Hanson, D. L. et al.
System: The UNT Digital Library
A simple way of characterizing x-ray downwards-deflecting mirror-bender assemblies using the long trace profiler (open access)

A simple way of characterizing x-ray downwards-deflecting mirror-bender assemblies using the long trace profiler

A simple device composed of a modular double-pentaprism system that enables the long trace profiler (LTP) to measure mirrors in nonconventional ways, i.e., in the vertical-downward and sideways positions, has been devised and implemented in the Advanced Photon Source (APS) long trace profiler (LTP II). The systems is very useful in calibrating mirror-bender assemblies. This paper describes the system and gives results of measurements performed with it on a mirror used at the APS.
Date: November 22, 1999
Creator: Assoufid, L. & Her, P.
System: The UNT Digital Library
New Results From the LASS (Large Aperture Superconducting Solenoid) Spectrometer (open access)

New Results From the LASS (Large Aperture Superconducting Solenoid) Spectrometer

New results are presented from analyses of several mesonic and baryonic states containing one or more strange quarks. The data are taken from a high statistics (4 events/nb) study of K p interactions at 11 GeV/c carried out in the LASS Spectrometer at SLAC. New information is reported on the underlying K* states and also evidence for selective coupling of K eta to the K*'s; on the strangeonium members of the axial vector nonets in the K anti K channel; and on evidence for an * state.
Date: June 22, 1987
Creator: Aston, D.; Awaji, N.; Bienz, T.; Bird, F.; D'Amore, J.; Dunwoodie, W. et al.
System: The UNT Digital Library
Cascading effects of COVID-19 on population mobility and air quality: An exploration including place characteristics using geovisualization (open access)

Cascading effects of COVID-19 on population mobility and air quality: An exploration including place characteristics using geovisualization

Article examining the population mobility and air quality before and after the lockdown (mandated restriction of activity) during the public health response to COVID-19. This article is part of the Special Issue on COVID-19.
Date: January 22, 2022
Creator: Atkinson, Samuel F.; Kala, Abhishek K. & Tiwari, Chetan
System: The UNT Digital Library
Signals from flavor changing scalar currents at the future colliders (open access)

Signals from flavor changing scalar currents at the future colliders

We present a general phenomenological analysis of a class of Two Higgs Doublet Models with Flavor Changing Neutral Currents arising at the tree level. The existing constraints mainly affect the couplings of the first two generations of quarks, leaving the possibility for non negligible Flavor Changing couplings of the top quark open. The next generation of lepton and hadron colliders will offer the right environment to study the physics of the top quark and to unravel the presence of new physics beyond the Standard Model. In this context we discuss some interesting signals from Flavor Changing Scalar Neutral Currents.
Date: November 22, 1996
Creator: Atwood, D.; Reina, L. & Soni, A.
System: The UNT Digital Library
Improved Measurement of the CKM Angle gamma in B^-+ to D^(*) K^(*)-+Decays with a Dalitz Plot Analysis of D Decays to K_S^0 pi+ pi- and K_S^0 K+ K- (open access)

Improved Measurement of the CKM Angle gamma in B^-+ to D^(*) K^(*)-+Decays with a Dalitz Plot Analysis of D Decays to K_S^0 pi+ pi- and K_S^0 K+ K-

We report on an improved measurement of the Cabibbo-Kobayashi-Maskawa CP-violating phase {gamma} through a Dalitz plot analysis of neutral D meson decays to K{sub s}{sup 0}{pi}{sup +}{pi}{sup -} and K{sub s}{sup 0}K{sup +}K{sup -} produced in the processes B{sup {-+}} {yields} DK{sup {-+}}, B{sup {-+}} {yields} D* K{sup {-+}} with D* {yields} D{pi}{sup 0}, D{gamma}, and B{sup {-+}} {yields} DK*{sup {-+}} with K8{sup {-+}} {yields} K{sub S}{sup 0}{pi}{sup {-+}}. Using a sample of 383 million B{bar B} pairs collected by the BABAR detector, we measure {gamma} = (76 {+-} 22 {+-} 5{+-} 5){sup o} (mod 180{sup o}), where the first error is statistical, the second is the experimental systematic uncertainty and the third reflects the uncertainty on the description of the Dalitz plot distributions. The corresponding two standard deviation region is 29{sup o} < {gamma} < 122{sup o}. This result has a significance of direct CP violation ({gamma} {ne} 0) of 3.0 standard deviations.
Date: April 22, 2008
Creator: Aubert, B.
System: The UNT Digital Library
Search for Second-Class Currents in tau- -> omega.pi-.nu_tau (open access)

Search for Second-Class Currents in tau- -> omega.pi-.nu_tau

We report an analysis of {tau}{sup -} decaying into {omega}{pi}{sup -} {nu}{sub {tau}} with {omega} {yields} {pi}{sup +}{pi}{sup -}{pi}{sup 0} using a data sample containing nearly 320 million {tau} pairs collected with the BABAR detector at the PEP-II B-Factory. We find no evidence for second-class currents and we set an upper limit of 0.69% at 90% confidence level for the fraction of second-class currents in this decay mode.
Date: April 22, 2009
Creator: Aubert, B.
System: The UNT Digital Library
Determination of |Vub| from Measurementsof the Electron and Neutrino Momenta inInclusive Semileptonic B Decays (open access)

Determination of |Vub| from Measurementsof the Electron and Neutrino Momenta inInclusive Semileptonic B Decays

None
Date: June 22, 2005
Creator: Aubert, B.; Barate, R.; Boutigny, D.; Couderc, F.; Karyotakis, Y.; Lees, J. P. et al.
System: The UNT Digital Library
Measurement of the B0 to D* D_s*+ and D_s+ to phi pi+ Branching Fractions (open access)

Measurement of the B0 to D* D_s*+ and D_s+ to phi pi+ Branching Fractions

The authors present measurements of the branching fractions {Beta}(B{sup 0} {yields} D*{sup -}D*{sub s}{sup +}) and {Beta}(D{sub s}{sup +} {yields} {phi}{pi}{sup +}), based on 123 x 10{sup 6} {Upsilon}(4S) {yields} B{bar B} decays collected by the BABAR detector at the PEP-II asymmetric-energy e{sup +}e{sup -} B factory. A partial reconstruction technique is used to measure {Beta}(B{sup 0} {yields} D*{sup -}D*{sub s}{sup +}) and the decay chain is fully reconstructed to measure the branching fraction product {Beta}(B{sup 0} {yields} D*{sup -} D*{sub s}{sup +}) x {Beta}(D{sub s}{sup +} {yields} {phi}{pi}{sup +}). Comparing these two measurements provides a model-independent determination of the D{sub s}{sup +} {yields} {phi}{pi}{sup +} branching fraction. They obtain {Beta}(B{sup 0} {yields} D*{sup -}D*{sub s}{sup +}) = (1.88 {+-} 0.09 {+-} 0.17)% and {Beta}(D{sub s}{sup +} {yields} {phi}{pi}{sup +}) = (4.81 {+-} 0.52 {+-} 0.38)%, where the first uncertainties are statistical and the second systematic.
Date: June 22, 2005
Creator: Aubert, B.; Barate, R.; Boutigny, D.; Couderc, F.; Karyotakis, Y.; Lees, J. P. et al.
System: The UNT Digital Library
Correlated Leading Baryon-antibaryon Production in e+e- to ccbar to Lambda_c+ antiLambda_c- X (open access)

Correlated Leading Baryon-antibaryon Production in e+e- to ccbar to Lambda_c+ antiLambda_c- X

We present a study of 649 {+-} 35 e{sup +}e{sup -} {yields} c{bar c} events produced at {radical}s {approx} 10.6 GeV containing both a {Lambda}{sub c}{sup +} baryon and a {bar {Lambda}}{sub c}{sup -} antibaryon. The number observed is roughly four times that expected if the leading charmed hadron types are uncorrelated, confirming an observation by the CLEO Collaboration. We find a 2-jet topology in these events but very few additional baryons, demonstrating that the primary c and {bar c} are predominantly contained in a correlated baryon-antibaryon system. In addition to the charmed baryons we observe on average 2.6 {+-} 0.2 charged intermediate mesons, predominantly pions, carrying 65% of the remaining energy.
Date: August 22, 2011
Creator: Aubert, B.; Karyotakis, Y.; Lees, J. P.; Poireau, V.; Prencipe, E.; Prudent, X. et al.
System: The UNT Digital Library
Observation of B^+\to\eta\rho^+ and Search for B^0 Decays to\eta^\prime\eta, \eta\pi^0, \eta^\prime\pi^0, and \omega\pi^0 (open access)

Observation of B^+\to\eta\rho^+ and Search for B^0 Decays to\eta^\prime\eta, \eta\pi^0, \eta^\prime\pi^0, and \omega\pi^0

The authors present measurements of branching fractions for five B-meson decays to two-body charmless final states. The data, collected with the BABAR detector at the Stanford Linear Accelerator Center, represent 459 million B{bar B} pairs. The results for branching fractions are, in units of 10{sup -6} (upper limits at 90% C.L.): {Beta}(B{sup +} {yields} {eta}{rho}{sup +}) = 9.9 {+-} 1.2 {+-} 0.8, {Beta}(B{sup 0} {yields} {eta}{prime}{eta}) = 0.5 {+-} 0.4 {+-} 0.1 (< 1.2), {Beta}(B{sup 0} {yields} {eta}{pi}{sup 0}) = 0.9 {+-} 0.4 {+-} 0.1 (< 1.5), {Beta}(B{sup 0} {yields} {eta}{prime}{pi}{sup 0}) = 0.9 {+-} 0.4 {+-} 0.1 (< 1.5), and {Beta}(B{sup 0}{sup 0} {yields} {omega}{pi}{sup 0}) = {eta}{rho}{sup +} mode, they measure the charge asymmetry {Alpha}{sub ch} (B{sup +} {yields} {eta}{rho}{sup +}) = 0.13 {+-} 0.11 {+-} 0.02.
Date: April 22, 2008
Creator: Aubert, Bernard; Bona, Marcella; Karyotakis, Y.; Lees, J. P.; Poireau, V.; Prencipe, E. et al.
System: The UNT Digital Library
Image Processing And Control Of A Programmable Spatial Light Modulator For Spatial Beam Shaping (open access)

Image Processing And Control Of A Programmable Spatial Light Modulator For Spatial Beam Shaping

None
Date: January 22, 2013
Creator: Awwal, A. S.; Orth, C.; Tse, E.; Matone, J.; Paul, M.; Hardy, C. et al.
System: The UNT Digital Library
Design and implementation of Dilation X-ray Imager for National Ignition Facility "DIXI" (open access)

Design and implementation of Dilation X-ray Imager for National Ignition Facility "DIXI"

None
Date: August 22, 2013
Creator: Ayers, M. J.; Bell, P. M.; Bradley, D.; Chung, M.; Felker, B.; Hares, J. et al.
System: The UNT Digital Library
Real-time Data Access Monitoring in Distributed, Multi-petabyte Systems (open access)

Real-time Data Access Monitoring in Distributed, Multi-petabyte Systems

Petascale systems are in existence today and will become common in the next few years. Such systems are inevitably very complex, highly distributed and heterogeneous. Monitoring a petascale system in real-time and understanding its status at any given moment without impacting its performance is a highly intricate task. Common approaches and off-the-shelf tools are either unusable, do not scale, or severely impact the performance of the monitored servers. This paper describes unobtrusive monitoring software developed at Stanford Linear Accelerator Center (SLAC) for a highly distributed petascale production data set. The paper describes the employed solutions, the lessons learned, the problems still to be addressed, and explains how the system can be reused elsewhere.
Date: April 22, 2008
Creator: Azemoon, Tofigh; Becla, Jacek, a=Hanushevsky, Andrew & Turri, Massimiliano
System: The UNT Digital Library
Computational Modeling of Heterogeneous Reactive Materials at the Mesoscale (open access)

Computational Modeling of Heterogeneous Reactive Materials at the Mesoscale

The mesoscopic processes of consolidation, deformation and reaction of shocked porous energetic materials are studied using shock physics analysis of impact on a collection of discrete ''crystals.'' Highly resolved three-dimensional CTH simulations indicate that rapid deformation occurs at material contact points causing large amplitude fluctuations of stress states with wavelengths of the order of several particle diameters. Localization of energy produces ''hot-spots'' due to shock focusing and plastic work near internal boundaries as material flows into interstitial regions. Numerical experiments indicate that ''hot-spots'' are strongly influenced by multiple crystal interactions. Chemical reaction processes also produce multiple wave structures associated with particle distribution effects. This study provides new insights into the micromechanical behavior of heterogeneous energetic materials strongly suggesting that initiation and sustained reaction of shocked heterogeneous materials involves states distinctly different from single jump state descriptions.
Date: September 22, 1999
Creator: BAER, MARVIN R.
System: The UNT Digital Library
The Effect of Ramp Rate on the C49 to C54 Titanium Disilicide Phase Transformation from Ti and Ti(Ta) (open access)

The Effect of Ramp Rate on the C49 to C54 Titanium Disilicide Phase Transformation from Ti and Ti(Ta)

The C49 to C54 TiSi{sub 2} transformation temperature is shown to be reduced by increasing the ramp rate during rapid thermal processing and this effect is more pronounced for thinner initial Ti and Ti(Ta) films. Experiments were performed on blanket wafers and on wafers that had patterned polycrystalline Si lines with Si{sub 3}N{sub 4} sidewall spacers. Changing the ramp rate caused no change in the transformation temperature for 60 nm blanket Ti films. For blanket Ti films of 25 or 40 nm, however, increasing the ramp rate from 7 to 180 C/s decreased the transformation temperature by 15 C. Studies of patterned lines indicate that sheet resistance of narrow lines is reduced by increased ramp rates for both Ti and Ti(Ta) films, especially as the linewidths decrease below 0.4 {micro}m. This improvement is particularly pronounced for the thinnest Ti(Ta) films, which exhibited almost no linewidth effect after being annealed with a ramp rate of 75 C/s.
Date: September 22, 1999
Creator: BAILEY, GLENN A.; HU, YAO ZHI; SMITH, PAUL M. & TAY, SING PIN
System: The UNT Digital Library
THE BC CRIBS & TRENCHES GEOPHYSICAL CHARACTERIZATION PROJECT ONE STEP FORWARD IN HANFORDS CLEANUP PROCESS (open access)

THE BC CRIBS & TRENCHES GEOPHYSICAL CHARACTERIZATION PROJECT ONE STEP FORWARD IN HANFORDS CLEANUP PROCESS

A geophysical characterization project was conducted at the BC Cribs and Trenches Area, located south of 200 East at the Hanford Site. The area consists of 26 waste disposal trenches and cribs, which received approximately 30 million gallons of liquid waste from the uranium recovery process and the ferrocyanide processes associated with wastes generated by reprocessing nuclear fuel. Waste discharges to BC Cribs contributed perhaps the largest liquid fraction of contaminants to the ground in the 200 Areas. The site also includes possibly the largest inventory of Tc-99 ever disposed to the soil at Hanford with an estimated quantity of 400 Ci. Other waste constituents included high volumes of nitrate and U-238. The geophysical characterization at the 50 acre site primarily included high resolution resistivity (HRR). The resistivity technique is a non-invasive method by which electrical resistivity data are collected along linear transects, and data are presented as continuous profiles of subsurface electrical properties. The transects ranged in size from about 400-700 meters and provided information down to depths of 60 meters. The site was characterized by a network of 51 HRR lines with a total of approximately 19.7 line kilometers of data collected parallel and perpendicular to the trenches …
Date: February 22, 2006
Creator: BENECKE, MN.W.
System: The UNT Digital Library
Transversely Polarized L Production. (open access)

Transversely Polarized L Production.

Transversely polarized {Lambda} production in hard scattering processes is discussed in terms of a leading twist T-odd fragmentation function which describes the fragmentation of an unpolarized quark into a transversely polarized {Lambda}. We focus on the properties of this function and its relevance for the RHIC and HERMES experiments.
Date: May 22, 2000
Creator: BORER, D.
System: The UNT Digital Library