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Amec Geomatrix/Ara Groundwater Remediaiton Trip Report
City of Rialto, Well No.3 Demonstration System Integration Project, and Baldwin Park Operable Unit, Baldwin Park, California. The groundwater remediation contractors are AMEC Geomatrix and ARA. The sites were visited on July 22, 2008. Fluor Hanford and the U.S. Department of Energy are currently looking at a variety of alternatives to capture carbon tetrachloride, nitrates, and other COCs from 200-ZP-l groundwater. A few of the more important objectives of our visits were to: (1) Evaluate the treatment systems being used by AMEC Geomatrix to address VOCs, perchlorate, NDMA, 1,4,-Dioxane, and 1,2,3 TCP in a drinking water source; (2) Evaluate how effective these treatment methods have been; (3) Determine the types of problems they have encountered with these treatment systems and how they addressed these problems; (4) Determine the types of secondary wastes being generated by the system; (5) Determine how clean of an operation these companies run; and (6) Determine if the site is worth being visited by DOE-RL at a later date.
Date:
August 7, 2008
Creator:
Simmons, S. A.; Hodgson, K. M. & Byrnes, M. E.
Object Type:
Report
System:
The UNT Digital Library
FY07 LDRD Final Report Development of Hot, LTE-tunable Radiation Sources for Material Science Studies
None
Date:
February 7, 2008
Creator:
Schneider, M
Object Type:
Report
System:
The UNT Digital Library
Wakefield and RF Kicks Due to Coupler Asymmetry in TESLA-Type Accelerating Cavities
In a future linear collider, such as the International Linear Collider (ILC), trains of high current, low emittance bunches will be accelerated in a linac before colliding at the interaction point. Asymmetries in the accelerating cavities of the linac will generate fields that will kick the beam transversely and degrade the beam emittance and thus the collider performance. In the main linac of the ILC, which is filled with TESLA-type superconducting cavities, it is the fundamental (FM) and higher mode (HM) couplers that are asymmetric and thus the source of such kicks. The kicks are of two types: one, due to (the asymmetry in) the fundamental RF fields and the other, due to transverse wakefields that are generated by the beam even when it is on axis. In this report we calculate the strength of these kicks and estimate their effect on the ILC beam. The TESLA cavity comprises nine cells, one HM coupler in the upstream end, and one (identical, though rotated) HM coupler and one FM coupler in the downstream end (for their shapes and location see Figs. 1, 2) [1]. The cavity is 1.1 m long, the iris radius 35 mm, and the coupler beam pipe radius …
Date:
July 7, 2008
Creator:
Bane, K. L. F.; Adolphsen, C.; Li, Z.; Dohlus, M.; Zagorodnov, I.; Gonin, I. et al.
Object Type:
Article
System:
The UNT Digital Library
Materials Technology Support for Radioisotope Power Systems Final Report
Over the period of this sponsored research, UDRI performed a number of materials related tasks that helped to facilitate increased understanding of the properties and applications of a number of candidate program related materials including; effects of neutron irradiation on tantalum alloys using a 500kW reactor, thermodynamic based modeling of the chemical species in weld pools, and the application of candidate coatings for increased oxidation resistance of FWPF (Fine Weave Pierced Fabric) modules.
Date:
October 7, 2008
Creator:
Kramer, Daniel P. & Barklay, Chadwick D.
Object Type:
Report
System:
The UNT Digital Library
The Role of Collinear Photons In the Rare Decay B to X_s ell ell
We review the phenomenology of the rare decay {bar B} {yields} X{sub s}{ell}{sup +}{ell}{sup -}. We present the results of a detailed phenomenological analysis and discuss the role of the decay in the search for new physics at present and future colliders. Moreover, we extensively elaborate on the size of electromagnetic logarithms ln(m{sub b}{sup 2}/m{sub {ell}}{sup 2}) in view of experimental cuts. We point out the differences in the analyses of BaBar and Belle and give suggestions on how to treat collinear photons in the experimental analyses. These recommendations correspond precisely to theoretical prescriptions and can be combined with measurements performed at a Super-B factory.
Date:
August 7, 2008
Creator:
Huber, T.; Hurth, T. & Lunghi, E.
Object Type:
Article
System:
The UNT Digital Library
The powers of deconfinement
The trace anomaly of gluodynamics encodes the breakdown of classical scale invariance due to interactions around the deconfinement phase transition. While it is expected that at high temperatures perturbation theory becomes applicable we show that current lattice calculations are far from the perturbative regime and are dominated instead by inverse even power corrections in the temperature, while the total perturbative contribution is estimated to be extremely small and compatible with zero within error bars. We provide an interpretation in terms of dimension-two gluon condensate of the dimensionally reduced theory which value agrees with a similar analysis of power corrections from available lattice data for the renormalized Polyakov loop and the heavy quark-antiquark free energy in the deconfined phase of QCD [1,2].
Date:
July 7, 2008
Creator:
Megias,E.; Ruiz Arriola, E.; Megias, E. & Salcedo, L.L.
Object Type:
Article
System:
The UNT Digital Library
Strongly Interacting Matter at High Energy Density
This lecture concerns the properties of strongly interacting matter (which is described by Quantum Chromodynamics) at very high energy density. I review the properties of matter at high temperature, discussing the deconfinement phase transition. At high baryon density and low temperature, large N{sub c} arguments are developed which suggest that high baryonic density matter is a third form of matter, Quarkyonic Matter, that is distinct from confined hadronic matter and deconfined matter. I finally discuss the Color Glass Condensate which controls the high energy limit of QCD, and forms the low x part of a hadron wavefunction. The Glasma is introduced as matter formed by the Color Glass Condensate which eventually thermalizes into a Quark Gluon Plasma.
Date:
September 7, 2008
Creator:
McLerran, L.
Object Type:
Article
System:
The UNT Digital Library
The dipole picture in DIS: saturation and heavy quarks
We discuss the description of the proton structure function within the dipole factorization framework. We parameterize the forward dipole amplitude to account for saturation as predicted by the small-x QCD evolution equations. Contrarily to previous models, the saturation scale does not decrease when taking heavy quarks into account. We show that the same dipole amplitude also allows to reproduce diffractive data and exclusive vector meson production.
Date:
April 7, 2008
Creator:
Soyez,G.
Object Type:
Article
System:
The UNT Digital Library
Quantum Monte Carlo Assessment of the Relevance of Electronic Correlations in Defects and EOS in Metals
We have developed a highly accurate computational capability to calculate the equation of state (EOS) and defect formation energies of metallic systems. We are using a newly developed algorithm that enables the study of metallic systems with quantum Monte Carlo (QMC) methods. To date, technical limitations have restricted the application of QMC methods to semiconductors, insulators and the homogeneous electron gas. Using this new 'QMC for metals' we can determine, for the first time, the significance of correlation effects in the EOS and in the formation energies of point defects, impurities, surfaces and interfaces in metallic systems. These calculations go beyond the state-of-the-art accuracy which is currently obtained with Density Functional Theory approaches. Such benchmark calculations can provide more accurate predictions for the EOS and the formation energies of vacancies and interstitials in simple metals. These are important parameters in determining the mechanical properties as well as the micro-structural evolution of metals in irradiated materials or under extreme conditions. We describe the development of our 'QMC for metals' code, which has been adapted to run efficiently on a variety of computer architectures including BG/L. We present results of the first accurate quantum Monte Carlo calculation of an EOS of a …
Date:
February 7, 2008
Creator:
Hood, R Q; Williamson, A J; Dubois, J L & Reboredo, F A
Object Type:
Report
System:
The UNT Digital Library
Progress in Large Period Multilayer Coatings for High Harmonic and Solar Applications
Multilayer coatings for normal incidence optics designed for the long wavelength region (25 nm < {lambda} < 50 nm) are particularly challenging due to the few number of layers that can be utilized in the reflection. Recently, Mg/SiC multilayers have been fabricated with normal incidence reflectivity in the vicinity of 40% for wavelengths near the He-II line at 30.4 nm. Motivated by this success we have investigated the use of a tri-band multilayer to increase the bandwidth while maintaining the reflectivity. The multilayers were deposited by conventional magnetron sputtering. Using Mg/SiC bilayers a reflectivity of 45% was achieved at 27 to 32 nm at an angle of 5 deg from normal. The Mg/Sc/SiC multilayer systems have also been investigated. It obtained a near normal incidence reflectivity of 35% while increasing the bandwidth by a factor of 2. These results are very encouraging for the possibility of more widespread applications of normal incidence optics in high harmonic applications.
Date:
January 7, 2008
Creator:
Jones, Juanita; Aquila, Andrew; Salmassi, Farhad & Gullikson, Eric
Object Type:
Article
System:
The UNT Digital Library
Final Report Fermionic Symmetries and Self consistent Shell Model
In this final report in the field of theoretical nuclear physics we note important accomplishments.We were confronted with "anomoulous" magnetic moments by the experimetalists and were able to expain them. We found unexpected partial dynamical symmetries--completely unknown before, and were able to a large extent to expain them.The importance of a self consistent shell model was emphasized.
Date:
November 7, 2008
Creator:
Zamick, Larry
Object Type:
Report
System:
The UNT Digital Library
Characterization of the effect of short pulse exposure on laser damage size, morphology, and conditioning in wide band gap materials
The first objective of this proposal was to develop a fundamental understanding of how short-pulse (100 ps to 1 ns) laser parameters affect conditioning and damage initiation in KDP and DKDP crystals. In this study we experimentally determine the effect of short-pulse laser parameters including pulse duration, pulse shape, and fluence on conditioning effectiveness, pinpoint damage density, pinpoint size, and pinpoint morphology in crystals. Based on the experimental results we developed empirical models, which give insight into the underlying physics of energy deposition from short-pulse lasers in KDP and DKDP crystals. The second objective of this proposal was to explore the mechanisms by which energy is deposited during damage in SiO{sub 2}. We have measured how laser parameters such as pulse duration, pulse shape, wavelength, and fluence are relevant to energy deposition, for initiation and growth on the surface of SiO{sub 2} optics.
Date:
February 7, 2008
Creator:
Carr, C. W.
Object Type:
Report
System:
The UNT Digital Library
Measurements and Analysis of Longitudinal HOM Driven Coupled Bunch Modes in PEP-II Rings
The growth rates of the longitudinal higher-order impedance-driven beam modes have greatly increased since the initial PEP-II design and commissioning. This increase is attributed to the addition of 6 1.2MW RF stations with 8 accelerating cavities in the HER and 2 1.2MW RF stations with 4 accelerating cavities in the LER, which allowed operations at twice the design current and almost four times the luminosity. As a result, the damping requirements for the longitudinal feedback have greatly increased since the design, and the feedback filters and control schemes have evolved during PEP-II operations. In this paper, growth and damping rate data for the higher-order mode (HOM) driven coupled-bunch modes are presented from various PEP-II runs and are compared with historical estimates during commissioning. The effect of noise in the feedback processing channel is also studied. Both the stability and performance limits of the system are analyzed.
Date:
July 7, 2008
Creator:
Mastorides, T; Rivetta, C.; Fox, J. D. & Winkle, D. Van
Object Type:
Article
System:
The UNT Digital Library
Applications of Lagrangian Dispersion Modeling to the Analysis of Changes in the Specific Absorption of Elemental Carbon
We use a Lagrangian dispersion model driven by a mesoscale model with four-dimensional data assimilation to simulate the dispersion of elemental carbon (EC) over a region encompassing Mexico City and its surroundings, the study domain for the 2006 MAX-MEX experiment, which was a component of the MILAGRO campaign. The results are used to identify periods when biomass burning was likely to have had a significant impact on the concentrations of elemental carbon at two sites, T1 and T2, downwind of the city, and when emissions from the Mexico City Metropolitan Area (MCMA) were likely to have been more important. They are also used to estimate the median ages of EC affecting the specific absorption of light, aABS, at 870 nm as well as to identify periods when the urban plume from the MCMA was likely to have been advected over T1 and T2. Values of aABS at T1, the nearer of the two sites to Mexico City, were smaller at night and increased rapidly after mid-morning, peaking in the mid-afternoon. The behavior is attributed to the coating of aerosols with substances such as sulfate or organic carbon during daylight hours, but such coating appears to be limited or absent at …
Date:
March 7, 2008
Creator:
Doran, J. C.; Fast, Jerome D.; Barnard, James C.; Laskin, Alexander; Desyaterik, Yury; Gilles, Marry K. et al.
Object Type:
Article
System:
The UNT Digital Library
Real Time Grid Reliability Management 2005
The increased need to manage California?s electricity grid in real time is a result of the ongoing transition from a system operated by vertically-integrated utilities serving native loads to one operated by an independent system operator supporting competitive energy markets. During this transition period, the traditional approach to reliability management -- construction of new transmission lines -- has not been pursued due to unresolved issues related to the financing and recovery of transmission project costs. In the absence of investments in new transmission infrastructure, the best strategy for managing reliability is to equip system operators with better real-time information about actual operating margins so that they can better understand and manage the risk of operating closer to the edge. A companion strategy is to address known deficiencies in offline modeling tools that are needed to ground the use of improved real-time tools. This project: (1) developed and conducted first-ever demonstrations of two prototype real-time software tools for voltage security assessment and phasor monitoring; and (2) prepared a scoping study on improving load and generator response models. Additional funding through two separate subsequent work authorizations has already been provided to build upon the work initiated in this project.
Date:
July 7, 2008
Creator:
Eto, Joe; Eto, Joe; Lesieutre, Bernard; Lewis, Nancy Jo & Parashar, Manu
Object Type:
Report
System:
The UNT Digital Library
Metal-insulator transition by isovalent anion substitution in Ga1-xMnxAs: Implications to ferromagnetism
We have investigated the effect of partial isovalent anion substitution in Ga1-xMnxAs on electrical transport and ferromagnetism. Substitution of only 2.4percent of As by P induces a metal-insulator transition at a constant Mn doping of x=0.046 while the replacement of 0.4 percent As with N results in the crossover from metal to insulator for x=0.037. This remarkable behavior is consistent with a scenario in which holes located within an impurity band are scattered by alloy disorder in the anion sublattice. The shorter mean free path of holes, which mediate ferromagnetism, reduces the Curie temperature TC from 113 K to 60 K (100 K to 65 K) upon the introduction of 3.1 percent P (1percent N) into the As sublattice.
Date:
February 7, 2008
Creator:
Stone, P. R.; Alberi, K.; Tardif, S. K. Z.; Beeman, J. W.; Yu, K. M.; Walukiewicz, W. et al.
Object Type:
Article
System:
The UNT Digital Library
New Observables In the Decay Mode \bar B_d \-->\bar K^{0*} \ell^+ \ell^-
We discuss the large set of observables available from the angular distributions of the decay {bar B}{sub d} {yields} {bar K}*{sup 0}{ell}{sup +}{ell}{sup -}. We present a NLO analysis of all observables based on the QCD factorization approach in the low-dilepton mass region and an estimate of {Lambda}/m{sub b} corrections. Moreover, we discuss their sensitivity to new physics. We explore the experimental sensitivities at LHCb (10 fb{sup -1}) and SuperLHCb (100 fb{sup -1}) based on a full-angular fit method and explore the sensitivity to right handed currents. We also show that the previously discussed transversity amplitude A{sub T}{sup (1)} cannot be measured at the LHCb experiment or at future B factory experiments as it requires a measurement of the spin of the final state particles.
Date:
August 7, 2008
Creator:
Egede, U.; /Imperial Coll., London; Hurth, T.; /SLAC, /CERN; Matias, J.; Ramon, M. et al.
Object Type:
Article
System:
The UNT Digital Library
A Method to Increase Current Density in a Mono Element Internal Tin Processed Superconductor Utilizing Zr Oxide to Refine Grain Size
The effect of Oxygen on (Nb1Zr)3Sn multifilament conductors manufactured by the Mono Element Internal Tin (MEIT) process was explored to improve the current density by refining the grain size. This followed work first done by General Electric on the Nb3Sn tape process. Techniques to fabricate the more difficult Nb1Zr composites are described and allowed fabrication of long lengths of .254 mm diameter wire from an 88.9 mm diameter billet. Oxygen was incorporated through the use of SnO2 mixed with tin powder and incorporated into the core. These were compared to samples with Ti+Sn and Cu+Sn cores. Heat treatments covered the range of 700 C to 1000 C. Current density vs. H, grain size, and reaction percentages are provided for the materials tested. The Oxygen gave superior results in the temperature range of 815-1000 C. It also stabilized the filament geometry of the array in comparison to the other additions at the higher temperatures. At 815 C a peak in layer Jc yielded values of 2537 A/mm2 at 12 T and 1353 A/mm2 at 15T, 8-22% and 30-73% greater respectively than 700 C values. Results with Oxygen at high temperature show the possibility of high speed continuous reaction of the composite …
Date:
April 7, 2008
Creator:
Bruce A. Zeitlin, Eric Gregory
Object Type:
Report
System:
The UNT Digital Library
Measurement of Semileptonic B Decays Into Orbitally-Excited Charm Mesons
The authors present a study of B decays into semileptonic final states containing charged and neutral D{sub 1}(2420) and D*{sub 2}(2460). The analysis is based on a data sample of 208 fb{sup -1} collected at the {Upsilon}(4S) resonance with the BABAR detector at the PEP-II asymmetric-energy B Factory at SLAC. With a simultaneous fit to four different decay chains, the semileptonic branching fractions are extracted from measurements of the mass difference {Delta}m = m(D**)-m(D) distributions. Product branching fractions are determined to be {Beta}(B{sup +} {yields} D{sub 1}{sup 0}{ell}{sup +}{nu}{sub {ell}}) x {Beta}(D{sub 1}{sup 0} {yields} D*{sup +}{pi}{sup -}) = (2.97 {+-} 0.17 {+-} 0.17) x 10{sup -3}, {Beta}(B{sup +} {yields} D*{sub 2}{sup 0}{ell}{sup +}{nu}{sub {ell}}) x {Beta}(D*{sub 2}{sup 0} {yields} D{sup (*)+} {pi}{sup -}) = (2.29 {+-} 0.23 {+-} 0.21) x 10{sup -3}, {Beta}(B{sup 0} {yields} D{sub 1}{sup -}{ell}{sup +}{nu}{sub {ell}}) x {Beta}(D{sub 1}{sup -} {yields} D*{sup 0}{pi}{sup -}) = (2.78 {+-} 0.24 {+-} 0.25) x 10{sup -3} and {Beta}(B{sup 0} {yields} D*{sub 2}{sup -}{ell}{sup +}{nu}{sub {ell}}) x {Beta}(D*{sub 2}{sup -} {yields} D{sup (*)0} {pi}{sup -}) = (1.77 {+-} 0.26 {+-} 0.11) x 10{sup -3}. In addition they measure the branching ratio {Lambda}(D*{sub 2} {yields} D{pi}{sup 0})/{Lambda}(D*{sub 2} {yields} D{sup …
Date:
August 7, 2008
Creator:
Aubert, Bernard; Bona, M.; Karyotakis, Y.; Lees, J. P.; Poireau, V.; Prencipe, E. et al.
Object Type:
Article
System:
The UNT Digital Library
High Spectral Resolution X-ray Observation of Magnetic CVs: EX Hya
In magnetic cataclysmic variables (CVs) the primary is a highly magnetized white dwarf (WD) whose field controls the accretion flow close to the WD, leading to a shock and accretion column that radiate chiefly in X-rays. We present preliminary results from a 500 ks Chandra HETG observation of the brightest magnetic CV EX Hya. From the observational dataset we are able to measure the temperature and density at different points of the cooling accretion column using sensitive line ratios. We also construct line-based light curves to search for rotational modulation of the X-ray emission.
Date:
April 7, 2008
Creator:
Luna, G; Brickhouse, N S & Mauche, C W
Object Type:
Article
System:
The UNT Digital Library
Petascale Simulation Initiative Summary Final Report
The Petascale Simulation Initiative LDRD project began in May 2004 and ended in April 2007. The overall goal of the project was to develop a computational model that would help LLNL simulation codes use petaflop-scale computers effectively, with specific emphasis on multiscale simulation. An early deliverable of the project was a report that surveyed a range of LLNL simulation codes so that the project would better understand their structure and needs. This report was titled 'Survey of Selected LLNL Unclassified Parallel Simulation Codes', UCRL-TR-207192. Based on the findings of this report, the project proceeded along two complementary paths. One goal was to develop a technique to reduce the amount of redundant calculation in a multiscale simulation by caching certain fine-scale simulation results as they were generated and then interpolating new values, where appropriate, based on cached data. This technique, which we call 'Adaptive Sampling', was successfully applied in a materials modeling simulation, and the results are detailed in a journal paper entitled 'Embedded polycrystal plasticity and adaptive sampling', UCRL-JRNL-226715. In this paper we showed an example multiscale simulation in which we were able to achieve a 40x speedup over the standard technique for doing the same problem and with very …
Date:
February 7, 2008
Creator:
May, J
Object Type:
Report
System:
The UNT Digital Library
Search for B+ Meson Decay to a1+ K*0
We present the preliminary result of a search for the decay B{sup {+-}} {yields} a{sub 1}{sup {+-}} K*{sup 0}. The data, collected with the BABAR detector at the Stanford Linear Accelerator Center, represent 465 million B{bar B} pairs produced in e{sup +}e{sup -} annihilation at the {Upsilon}(4S) energy. The result for the branching fraction is: {Beta}(B{sup +} {yields} a{sub 1}{sup +}K*{sup 0}) x {Beta}(a{sub 1}{sup +} {yields} {pi}{sup +}{pi}{sup -}{pi}{sup +}) = (0.7{sub -0.4-0.7}{sup +0.5+0.7}) x 10{sup -6}, corresponding to an upper limit at 90% confidence level of 1.6 x 10{sup -6}. The first error quoted is statistical, the second systematic.
Date:
August 7, 2008
Creator:
Aubert, B.
Object Type:
Article
System:
The UNT Digital Library
Shared Technology Transfer Program
The program established a collaborative process with domestic industries for the purpose of sharing Navy-developed technology. Private sector businesses were educated so as to increase their awareness of the vast amount of technologies that are available, with an initial focus on technology applications that are related to the Hydrogen, Fuel Cells and Infrastructure Technologies (Hydrogen) Program of the U.S. Department of Energy. Specifically, the project worked to increase industry awareness of the vast technology resources available to them that have been developed with taxpayer funding. NAVSEA-Carderock and the Houston Advanced Research Center teamed with Nicholls State University to catalog NAVSEA-Carderock unclassified technologies, rated the level of readiness of the technologies and established a web based catalog of the technologies. In particular, the catalog contains technology descriptions, including testing summaries and overviews of related presentations.
Date:
March 7, 2008
Creator:
Griffin, John M. & Haut, Richard C.
Object Type:
Report
System:
The UNT Digital Library
Tank 241-an-102 Multi-Probe Corrosion Monitoring System Project Lessons Learned
During 2007 and 2008, a new Multi-Probe Corrosion Monitoring System (MPCMS) was designed and fabricated for use in double-shell tank 241-AN-102. The system was successfully installed in the tank on May 1, 2008. The 241-AN-102 MPCMS consists of one 'fixed' in-tank probe containing primary and secondary reference electrodes, tank material electrodes, Electrical Resistance (ER) sensors, and stressed and unstressed corrosion coupons. In addition to the fixed probe, the 241-AN-102 MPCMS also contains four standalone coupon racks, or 'removable' probes. Each rack contains stressed and unstressed coupons made of American Society of Testing and Materials A537 CL1 steel, heat-treated to closely match the chemical and mechanical characteristics of the 241-AN-102 tank wall. These coupon racks can be removed periodically to facilitate examination of the attached coupons for corrosion damage. Along the way to successful system deployment and operation, the system design, fabrication, and testing activities presented a number of challenges. This document discusses these challenges and lessons learned, which when applied to future efforts, should improve overall project efficiency.
Date:
July 7, 2008
Creator:
Taylor, T.; Hagensen, A. & Kirch, N. W.
Object Type:
Report
System:
The UNT Digital Library