Ag BL Description for General Atomics (open access)

Ag BL Description for General Atomics

None
Date: December 9, 2013
Creator: Huntington, C.
Object Type: Report
System: The UNT Digital Library
What Limits the Gap in a Flat Dechirper for an X-ray FEL (open access)

What Limits the Gap in a Flat Dechirper for an X-ray FEL

None
Date: December 9, 2013
Creator: Bane, K. L. F. & Stupakov, G.
Object Type: Report
System: The UNT Digital Library
ZDC Effective Cross Section for Uranium-Uranium Collisions in Run 12 (open access)

ZDC Effective Cross Section for Uranium-Uranium Collisions in Run 12

N/A
Date: December 9, 2013
Creator: A., Drees
Object Type: Report
System: The UNT Digital Library
An FMEA Analysis for Photovoltaic Systems: Assessing Different System Configurations to Support Reliability Studies - Introduction to PRA Analysis for PV Systems (open access)
Assessment of Technologies Used to Characterize Wildlife Populations in the Offshore Environment (open access)

Assessment of Technologies Used to Characterize Wildlife Populations in the Offshore Environment

Wind energy development in the offshore environment can have both direct and indirect effects on wildlife, yet little is known about most species that use near-shore and offshore waters due in part to the difficulty involved in studying animals in remote, challenging environments. Traditional methods to characterize offshore wildlife populations include shipboard observations. Technological advances have provided researches with an array of technologies to gather information about fauna from afar. This report describes the use and application of radar, thermal and optical imagery, and acoustic detection technologies for monitoring birds, bats, and marine mammals in offshore environments.
Date: December 9, 2011
Creator: Duberstein, Corey A.; Tagestad, Jerry D. & Larson, Kyle B.
Object Type: Report
System: The UNT Digital Library
Computational Mechanics Research and Support for Aerodynamics and Hydraulics at TFHRC Year 1 Quarter 4 Progress Report. (open access)

Computational Mechanics Research and Support for Aerodynamics and Hydraulics at TFHRC Year 1 Quarter 4 Progress Report.

The computational fluid dynamics (CFD) and computational structural mechanics (CSM) focus areas at Argonne's Transportation Research and Analysis Computing Center (TRACC) initiated a project to support and compliment the experimental programs at the Turner-Fairbank Highway Research Center (TFHRC) with high performance computing based analysis capabilities in August 2010. The project was established with a new interagency agreement between the Department of Energy and the Department of Transportation to provide collaborative research, development, and benchmarking of advanced three-dimensional computational mechanics analysis methods to the aerodynamics and hydraulics laboratories at TFHRC for a period of five years, beginning in October 2010. The analysis methods employ well-benchmarked and supported commercial computational mechanics software. Computational mechanics encompasses the areas of Computational Fluid Dynamics (CFD), Computational Wind Engineering (CWE), Computational Structural Mechanics (CSM), and Computational Multiphysics Mechanics (CMM) applied in Fluid-Structure Interaction (FSI) problems. The major areas of focus of the project are wind and water effects on bridges - superstructure, deck, cables, and substructure (including soil), primarily during storms and flood events - and the risks that these loads pose to structural failure. For flood events at bridges, another major focus of the work is assessment of the risk to bridges caused by scour …
Date: December 9, 2011
Creator: Lottes, S.A.; Kulak, R.F. & Bojanowski, C.
Object Type: Report
System: The UNT Digital Library
CONFIRMATORY SURVEY RESULTS FOR PORTIONS OF THE ABB COMBUSTION ENGINEERING SITE IN WINDSOR, CONNECTICUT DURING THE FALL OF 2011 (open access)

CONFIRMATORY SURVEY RESULTS FOR PORTIONS OF THE ABB COMBUSTION ENGINEERING SITE IN WINDSOR, CONNECTICUT DURING THE FALL OF 2011

From the mid-1950s until mid-2000, the Combustion Engineering, Inc. (CE) site in Windsor, Connecticut (Figure A-1) was involved in the research, development, engineering, production, and servicing of nuclear fuels, systems, and services. The site is currently undergoing decommissioning that will lead to license termination and unrestricted release in accordance with the requirements of the License Termination Rule in 10 CFR Part 20, Subpart E. Asea Brown Boveri Incorporated (ABB) has been decommissioning the CE site since 2001.
Date: December 9, 2011
Creator: Adams, Wade C.
Object Type: Report
System: The UNT Digital Library
Constructing Amplitudes from Their Soft Limits (open access)

Constructing Amplitudes from Their Soft Limits

The existence of universal soft limits for gauge-theory and gravity amplitudes has been known for a long time. The properties of the soft limits have been exploited in numerous ways; in particular for relating an n-point amplitude to an (n-1)-point amplitude by removing a soft particle. Recently, a procedure called inverse soft was developed by which 'soft' particles can be systematically added to an amplitude to construct a higher-point amplitude for generic kinematics. We review this procedure and relate it to Britto-Cachazo-Feng-Witten recursion. We show that all tree-level amplitudes in gauge theory and gravity up through seven points can be constructed in this way, as well as certain classes of NMHV gauge-theory amplitudes with any number of external legs. This provides us with a systematic procedure for constructing amplitudes solely from their soft limits.
Date: December 9, 2011
Creator: Boucher-Veronneau, Camille & Larkoski, Andrew J.
Object Type: Article
System: The UNT Digital Library
An Exploration of Catalytic Chemistry on Au/Ni(111) (open access)

An Exploration of Catalytic Chemistry on Au/Ni(111)

This project explored the catalytic oxidation chemistry that can be effected on a Au/Ni(111) surface alloy. A Au/Ni(111) surface alloy is a Ni(111) surface on which less than 60% of the Ni atoms are replaced at random positions by Au atoms. The alloy is produced by vapor deposition of a small amount of Au onto Ni single crystals. The Au atoms do not result in an epitaxial Au overlayer or in the condensation of the Au into droplets. Instead, Au atoms displace and then replace Ni atoms on a Ni(111) surface, even though Au is immiscible in bulk Ni. The two dimensional structure of the clean Ni surface is preserved. This alloy is found to stabilize an adsorbed peroxo-like O2 species that is shown to be the critical reactant in the low temperature catalytic oxidation of CO and that is suspected to be the critical reactant in other oxidation reactions. This investigation revealed a new, practically important catalyst for CO oxidation that has since been patented.
Date: December 9, 2011
Creator: Ceyer, Sylvia T.
Object Type: Report
System: The UNT Digital Library
Flux and Photon Spectral Index Distributions of Fermi-LAT Blazars and Contribution to the Extragalactic Gamma-ray Background (open access)

Flux and Photon Spectral Index Distributions of Fermi-LAT Blazars and Contribution to the Extragalactic Gamma-ray Background

We present a determination of the distributions of gamma-ray flux - the so called LogN-LogS relation - and photon spectral index for the 352 blazars detected with a greater than approximately seven sigma detection threshold and located above {+-} 20{sup o} Galactic latitude by the Large Area Telescope of the Fermi Gamma-ray Space Telescope in its first year catalog. Because the flux detection threshold depends on the photon index, the observed raw distributions do not provide the true LogN-LogS counts or the true distribution of the photon index. We use the non-parametric methods developed by Efron and Petrosian to reconstruct the intrinsic distributions from the observed ones which account for the data truncations introduced by observational bias and includes the effects of the possible correlation among the two variables. We demonstrate the robustness of our procedures using a simulated data set of blazars and then apply these to the real data and find that for the population as a whole the intrinsic flux distribution can be represented by a broken power law of slopes -2.37 {+-} 0.13 and -1.70 {+-} 0.26, and the intrinsic photon index distribution can be represented by a Gaussian with mean 2.41 {+-} 0.13 and 1{sigma} …
Date: December 9, 2011
Creator: Singal, J.; /KIPAC, Menlo Park /SLAC /Stanford U.; Petrosian, V.; /KIPAC, Menlo Park /SLAC /Stanford U., Phys. Dept. /Stanford U., Appl. Phys. Dept.; Ajello, M. & /KIPAC, Menlo Park /SLAC /Stanford U.
Object Type: Article
System: The UNT Digital Library
fy12 Summary Report on Liquid-Liquid Contactor Experiments for CFD Model Validation (open access)

fy12 Summary Report on Liquid-Liquid Contactor Experiments for CFD Model Validation

None
Date: December 9, 2011
Creator: Smith, M.; Mohamed, A.; Marin-Lafleche, A.; Lewis, E.; Derstine, K.; Lee, C.H. et al.
Object Type: Report
System: The UNT Digital Library
FY2011 Status Report on SN2ND Neutronics Solver Development. (open access)

FY2011 Status Report on SN2ND Neutronics Solver Development.

None
Date: December 9, 2011
Creator: Smith, M. A.; Mohamed, A.; Marin-Lafleche, A.; Lee, C. H. & Yang, W. S.
Object Type: Report
System: The UNT Digital Library
Generation of non-axisymmetric scrape-off layer perturbations for controlling tokamak edge plasma profiles and stability (open access)

Generation of non-axisymmetric scrape-off layer perturbations for controlling tokamak edge plasma profiles and stability

None
Date: December 9, 2011
Creator: Joseph, I.; Cohen, R. H.; Rognlien, T. D. & Ryutov, D. D.
Object Type: Article
System: The UNT Digital Library
Lessons Learned From a Site-Wide Power Outage (open access)

Lessons Learned From a Site-Wide Power Outage

None
Date: December 9, 2011
Creator: Bartelt, John
Object Type: Article
System: The UNT Digital Library
Long-Baseline Neutrino Experiment (LBNE)Water Cherenkov Detector Basis of Estimate Forms and Backup Documentation LBNE Far Site Internal Review (December 6-9, 2011) (open access)

Long-Baseline Neutrino Experiment (LBNE)Water Cherenkov Detector Basis of Estimate Forms and Backup Documentation LBNE Far Site Internal Review (December 6-9, 2011)

Basis of Estimate (BOE) forms and backup documentation developed for the Water Cherenkov Detector (WCD) option for the far detector of the Long Baseline Neutrino Experiment (LBNE)
Date: December 9, 2011
Creator: Stewart, J.; Diwan, M.; Dolph, J.; Novakova, P.; Sharma, R.; Stewart, J. et al.
Object Type: Report
System: The UNT Digital Library
Long-Baseline Neutrino Experiment (LBNE) Water Cherenkov Detector Schedule and Cost Books LBNE Far Site Internal Review(December 6-9,2011) (open access)

Long-Baseline Neutrino Experiment (LBNE) Water Cherenkov Detector Schedule and Cost Books LBNE Far Site Internal Review(December 6-9,2011)

Schedule and Cost Books developed for the Water Cherenkov Detector (WCD) option for the far detector of the Long Baseline Neutrino Experiment (LBNE)
Date: December 9, 2011
Creator: Stewart, J.; Diwan, M.; Dolph, J.; Novakova, P.; Sharma, R.; Stewart, J. et al.
Object Type: Report
System: The UNT Digital Library
Precise Predictions for Z + 4 Jets at Hadron Colliders (open access)

Precise Predictions for Z + 4 Jets at Hadron Colliders

We present the cross section for production of a Z boson in association with four jets at the Large Hadron Collider, at next-to-leading order in the QCD coupling. When the Z decays to neutrinos, this process is a key irreducible background to many searches for new physics. Its computation has been made feasible through the development of the on-shell approach to perturbative quantum field theory. We present the total cross section for pp collisions at {radical}s = 7 TeV, after folding in the decay of the Z boson, or virtual photon, to a charged-lepton pair. We also provide distributions of the transverse momenta of the four jets, and we compare cross sections and distributions to the corresponding ones for the production of a W boson with accompanying jets.
Date: December 9, 2011
Creator: Ita, H.; Bern, Z.; Dixon, L.J.; Cordero, F.Febres; Kosower, D.A. & Maitre, D.
Object Type: Article
System: The UNT Digital Library
Scientific Discovery with the Blue Gene/L (open access)

Scientific Discovery with the Blue Gene/L

This project succeeded in developing key software optimization tools to bring fundamental QCD calculations of nucleon structure from the Terascale era through the Petascale era and prepare for the Exascale era. It also enabled fundamental QCD physics calculations and demonstrated the power of placing small versions of frontier emerging architectures at MIT to attract outstanding students to computational science. MIT also hosted a workshop September 19 2008 to brainstorm ways to promote computational science at top tier research universities and attract gifted students into the field, some of whom would provide the next generation of talent at our defense laboratories.
Date: December 9, 2011
Creator: Negele, John W.
Object Type: Report
System: The UNT Digital Library
Status of the ATF2 Lattices (open access)

Status of the ATF2 Lattices

The current status for the ATF2 Nominal and Ultra-low {beta}* lattices are presented in this paper. New lattice designs have been obtained in order to minimise the impact of the last interpretation of multipole measurements that have been included into the model. However, the new ATF2 Ultra-low design is not able to recover the expected vertical beam size at the IP with the current magnet distribution. Therefore, different quadrupole sorting have been studied. A significant gain is evident for the ATF2 Ultra-low lattice when sorting the magnets according to the skew-sextupolar components. The ATF2 Nominal lattice is also expected to benefit from the new sorting. Tuning results of the new ATF2 Ultra-low lattice under realistic imperfections are also reported.
Date: December 9, 2011
Creator: Marin, E.; Tomas, R.; Bambade, P.; Okugi, T.; Tauchi, T.; Terunuma, N. et al.
Object Type: Article
System: The UNT Digital Library
Study of B to pi l nu and B to rho l nu Decays and Determination of |V_ub| (open access)

Study of B to pi l nu and B to rho l nu Decays and Determination of |V_ub|

We present an analysis of exclusive charmless semileptonic B-meson decays based on 377 million B{bar B} pairs recorded with the BABAR detector at the {Upsilon} (4S) resonance. We select four event samples corresponding to the decay modes B{sup 0} {yields} {pi}{sup -}{ell}{sup +}{nu}, B{sup +} {yields} {pi}{sup 0}{ell}{sup +}{nu}, B{sup 0} {yields} {rho}{sup -}{ell}{sup +}{nu}, and B{sup +} {yields} {rho}{sup 0}{ell}{sup +}{nu}, and find the measured branching fractions to be consistent with isospin symmetry. Assuming isospin symmetry, we combine the two B {yields} {pi}{ell}{nu} samples, and similarly the two B {yields} {rho}{ell}{nu} samples, and measure the branching fractions {Beta}(B{sup 0} {yields} {pi}{sup -}{ell}{sup +}{nu}) = (1.41 {+-} 0.05 {+-} 0.07) x 10{sup -4} and {Beta}(B{sup 0} {yields} {rho}{sup 0}{ell}{sup +}{nu}) = (1.75 {+-} 0.15 {+-} 0.27) x 10{sup -4}, where the errors are statistical and systematic. We compare the measured distribution in q{sup 2}, the momentum transfer squared, with predictions for the form factors from QCD calculations and determine the CKM matrix element |V{sub ub}|. Based on the measured partial branching fraction for B {yields} {pi}{ell}{nu} in the range q{sup 2} < 12 GeV{sup 2} and the most recent LCSR calculations we obtain |V{sub ub}| = (3.78 {+-} 0.13{sub -0.40}{sup …
Date: December 9, 2011
Creator: del Amo Sanchez, P.; Lees, J. P.; Poireau, V.; Prencipe, E.; Tisserand, V.; Garra Tico, J. et al.
Object Type: Article
System: The UNT Digital Library
Study of di-pion Bottomonium Transitions and Search for the h_b(1P) State (open access)

Study of di-pion Bottomonium Transitions and Search for the h_b(1P) State

We study inclusive di-pion decays using a sample of 108 x 10{sup 6} {Upsilon}(3S) events recorded with the BABAR detector. We search for the decay mode {Upsilon}(3S) {yields} {pi}{sup +}{pi}{sup -}h{sub b} (1P) and find no evidence for the bottomonium spin-singlet state h{sub b}(1P) in the invariant mass distribution recoiling against the {pi}{sup +}{pi}{sup -} system. Assuming the h{sub b}(1P) mass to be 9.900 GeV/c{sup 2}, we measure the upper limit on the branching fraction {Beta}[{Upsilon}(3S) {yields} {pi}{sup +}{pi}{sup -}h{sub b}(1P)] < 1.2 x 10{sup -4}, at 90% confidence level. We also investigate the {chi}{sub bJ}(2P) {yields} {pi}{sup +}{pi}{sup -} {chi}{sub bJ}(1P), {Upsilon}(3S) {yields} {pi}{sup +}{pi}{sup -}{Upsilon}(2S), and {Upsilon}(2S) {yields} {pi}{sup +}{pi}{sup -}{Upsilon}(1S) di-pion transitions and present an improved measurement of the branching fraction of the {Upsilon}(3S) {yields} {pi}{sup +}{pi}{sup -}{Upsilon}(2S) decay and of the {Upsilon}(3S) - {Upsilon}(2S) mass difference.
Date: December 9, 2011
Creator: Lees, J. P.; Poireau, V.; Tisserand, V.; Garra Tico, J.; Grauges, E.; Martinelli, M. et al.
Object Type: Article
System: The UNT Digital Library
Theory of Microwave Instability and Coherent Synchrotron Radiation in Electron Storage Rings (open access)

Theory of Microwave Instability and Coherent Synchrotron Radiation in Electron Storage Rings

Bursting of coherent synchrotron radiation has been observed and in fact used to generate THz radiation in many electron storage rings. In order to understand and control the bursting, we return to the study of the microwave instability. In this paper, we will report on the theoretical understanding, including recent developments, of the microwave instability in electron storage rings. The historical progress of the theories will be surveyed, starting from the dispersion relation of coasting beams, to the work of Sacherer on a bunched beam, and ending with the Oide and Yokoya method of discretization. This theoretical survey will be supplemented with key experimental results over the years. Finally, we will describe the recent theoretical development of utilizing the Laguerre polynomials in the presence of potential-well distortion. This self-consistent method will be applied to study the microwave instability driven the impedances due to the coherent synchrotron radiation. Over the past quarter century, there has been steady progress toward smaller transverse emittances in electron storage rings used for synchrotron light sources, from tens of nm decades ago to the nm range recently. In contrast, there is not much progress made in the longitudinal plane. For an electron bunch in a typical …
Date: December 9, 2011
Creator: Cai, Y.
Object Type: Article
System: The UNT Digital Library
Transverse Emittance Reduction with Tapered Foil (open access)

Transverse Emittance Reduction with Tapered Foil

The idea of reducing transverse emittance with tapered energy-loss foil is proposed by J.M. Peterson in 1980s and recently by B. Carlsten. In this paper, we present the physical model of tapered energy-loss foil and analyze the emittance reduction using the concept of eigen emittance. The study shows that, to reduce transverse emittance, one should collimate at least 4% of particles which has either much low energy or large transverse divergence. The multiple coulomb scattering is not trivial, leading to a limited emittance reduction ratio. Small transverse emittances are of essential importance for the accelerator facilities generating free electron lasers, especially in hard X-ray region. The idea of reducing transverse emittance with tapered energy-loss foil is recently proposed by B. Carlsten [1], and can be traced back to J.M. Peterson's work in 1980s [2]. Peterson illustrated that a transverse energy gradient can be produced with a tapered energy-loss foil which in turn leads to transverse emittance reduction, and also analyzed the emittance growth from the associated multiple coulomb scattering. However, what Peterson proposed was rather a conceptual than a practical design. In this paper, we build a more complete physical model of the tapered foil based on Ref. [2], including …
Date: December 9, 2011
Creator: Jiao, Yi; Chao, Alex & Cai, Yunhai
Object Type: Article
System: The UNT Digital Library
CORROSION TESTING IN SIMULATED TANK SOLUTIONS (open access)

CORROSION TESTING IN SIMULATED TANK SOLUTIONS

Three simulated waste solutions representing wastes from tanks SY-102 (high nitrate, modified to exceed guidance limits), AN-107, and AY-102 were supplied by PNNL. Out of the three solutions tested, both optical and electrochemical results show that carbon steel samples corroded much faster in SY-102 (high nitrate) than in the other two solutions with lower ratios of nitrate to nitrite. The effect of the surface preparation was not as strong as the effect of solution chemistry. In areas with pristine mill-scale surface, no corrosion occurred even in the SY-102 (high nitrate) solution, however, corrosion occurred in the areas where the mill-scale was damaged or flaked off due to machining. Localized corrosion in the form of pitting in the vapor space of tank walls is an ongoing challenge to overcome in maintaining the structural integrity of the liquid waste tanks at the Savannah River and Hanford Sites. It has been shown that the liquid waste condensate chemistry influences the amount of corrosion that occurs along the walls of the storage tanks. To minimize pitting corrosion, an effort is underway to gain an understanding of the pitting response in various simulated waste solutions. Electrochemical testing has been used as an accelerated tool in …
Date: December 9, 2010
Creator: Hoffman, E.
Object Type: Report
System: The UNT Digital Library