The Role of a Detailed Configuration Accounting (DCA) Atomic Physics Package in Explaing the Energy Balance in Ignition Scale Hohlraums (open access)

The Role of a Detailed Configuration Accounting (DCA) Atomic Physics Package in Explaing the Energy Balance in Ignition Scale Hohlraums

None
Date: January 10, 2011
Creator: Rosen, M; Scott, H; Hinkel, D; Williams, E; Callahan, D; Town, R et al.
Object Type: Article
System: The UNT Digital Library
Dark Shadows (open access)

Dark Shadows

The U.S. Department of Energy's National Renewable Energy Laboratory, Sandia National Laboratories, the Solar Electric Power Association, the Utility Wind Integration Group, and the U.S. Department of Energy hosted a day-long public workshop on the variability of photovoltaic (PV) plants. The workshop brought together utilities, PV system developers, power system operators, and several experts to discuss the potential impacts of PV variability and uncertainty on power system operations.
Date: January 10, 2011
Creator: Mills, Andrew; Ahlstrom, Mark; Brower, Michael; Ellis, Abraham; George, Ray; Hoff, Tom et al.
Object Type: Article
System: The UNT Digital Library
Simulation of free-electron lasers seeded with broadband radiation (open access)

Simulation of free-electron lasers seeded with broadband radiation

The longitudinal coherence of free-electron laser (FEL) radiation can be enhanced by seeding the FEL with high harmonics of an optical laser pulse. The radiation produced by high-harmonic generation (HHG), however, has a fast-varying temporal profile that can violate the slowly varying envelope approximation and limited frequency window that is employed in conventional free-electron laser simulation codes. Here we investigate the implications of violating this approximation on the accuracy of simulations. On the basis of both analytical considerations and 1D numerical studies, it is concluded that, for most realistic scenarios, conventional FEL codes are capable of accurately simulating the FEL process even when the seed radiation violates the slowly varying envelope approximation. We additionally discuss the significance of filtering the harmonic content of broadband HHG seeds.
Date: March 10, 2011
Creator: Bajlekov, Svetoslav; Fawley, William; Schroeder, Carl; Bartolini, Riccardo & Hooker, Simon
Object Type: Article
System: The UNT Digital Library
Overview of the Facility Safeguardability Analysis (FSA) Process (open access)

Overview of the Facility Safeguardability Analysis (FSA) Process

The safeguards system of the International Atomic Energy Agency (IAEA) provides the international community with credible assurance that a State is fulfilling its nonproliferation obligations. The IAEA draws such conclusions from the evaluation of all available information. Effective and cost-efficient IAEA safeguards at the facility level are, and will remain, an important element of this “State-level” approach. Efficiently used, the Safeguards by Design (SBD) methodologies , , , now being developed can contribute to effective and cost-efficient facility-level safeguards. The Facility Safeguardability Assessment (FSA) introduced here supports SBD in three areas. 1. It describes necessary interactions between the IAEA, the State regulator, and the owner / designer of a new or modified facility to determine where SBD efforts can be productively applied, 2. It presents a screening approach intended to identify potential safeguard issues for; a) design changes to existing facilities; b) new facilities similar to existing facilities with approved safeguards approaches, and c) new designs, 3. It identifies resources (the FSA toolkit), such as good practice guides, design guidance, and safeguardability evaluation methods that can be used by the owner/designer to develop solutions for potential safeguards issues during the interactions with the State regulator and IAEA. FSA presents a …
Date: October 10, 2011
Creator: Bari, Robert A.; Hockert, John; Wonder, Edward F.; Johnson, Shirley J.; Wigeland, Roald & Zentner, Michael D.
Object Type: Report
System: The UNT Digital Library
Improvement of snowpack simulations in a regional climate model (open access)

Improvement of snowpack simulations in a regional climate model

To improve simulations of regional-scale snow processes and related cold-season hydroclimate, the Community Land Model version 3 (CLM3), developed by the National Center for Atmospheric Research (NCAR), was coupled with the Pennsylvania State University/NCAR fifth-generation Mesoscale Model (MM5). CLM3 physically describes the mass and heat transfer within the snowpack using five snow layers that include liquid water and solid ice. The coupled MM5–CLM3 model performance was evaluated for the snowmelt season in the Columbia River Basin in the Pacific Northwestern United States using gridded temperature and precipitation observations, along with station observations. The results from MM5–CLM3 show a significant improvement in the SWE simulation, which has been underestimated in the original version of MM5 coupled with the Noah land-surface model. One important cause for the underestimated SWE in Noah is its unrealistic land-surface structure configuration where vegetation, snow and the topsoil layer are blended when snow is present. This study demonstrates the importance of the sheltering effects of the forest canopy on snow surface energy budgets, which is included in CLM3. Such effects are further seen in the simulations of surface air temperature and precipitation in regional weather and climate models such as MM5. In addition, the snow-season surface albedo …
Date: January 10, 2011
Creator: Jin, J. & Miller, N. L.
Object Type: Article
System: The UNT Digital Library
Element-specific study of epitaxial NiO/Ag/CoO/Fe films grown on vicinal Ag(001) using photoemission electron microscopy (open access)

Element-specific study of epitaxial NiO/Ag/CoO/Fe films grown on vicinal Ag(001) using photoemission electron microscopy

NiO/Ag/CoO/Fe single crystalline films are grown epitaxially on a vicinal Ag(001) substrate using molecular beam epitaxy and investigated by photoemission electron microscopy. We find that after zero-field cooling, the in-plane Fe magnetization switches from parallel to perpendicular direction of the atomic steps of the vicinal surface at thinner CoO thickness but remains in its original direction parallel to the steps at thicker CoO thickness. CoO and NiO domain imaging result shows that both CoO/Fe and NiO/CoO spins are perpendicularly coupled, suggesting that the Fe magnetization switching may be associated with the rotatable-frozen spin transition of the CoO film.
Date: January 10, 2011
Creator: Meng, Y.; Li, J.; Tan, A.; Jin, E.; Son, J.; Park, J. S. et al.
Object Type: Article
System: The UNT Digital Library
Printability and inspectability of Defects on the EUV Mask for sub32nm Half Pitch HVM Application (open access)

Printability and inspectability of Defects on the EUV Mask for sub32nm Half Pitch HVM Application

The availability of defect-free masks remains one of the key challenges for inserting extreme ultraviolet lithography (EUVL) into high volume manufacturing, yet little data is available for understanding native defects on real masks. In this paper, a full field EUV mask is fabricated to see the printability of various defects on the mask. Programmed pit defect shows that minimum printable size of pits could be 17 nm of SEVD from the AIT. However 23.1nm in SEVD is printable from the EUV ADT. Defect printability and identification of its source along from blank fabrication to mask fabrication were studied using various inspection tools. Capture ratio of smallest printable defects was improved to 80% using optimized stack of metrical on wafer and state-of-art wafer inspection tool. Requirement of defect mitigation technology using fiducial mark are defined.
Date: January 10, 2011
Creator: Huh, S.; Kang, I. Y.; Kim, S. H.; Seo, H. S.; Kim, D.; Park, J. et al.
Object Type: Article
System: The UNT Digital Library
Muon Collider Progress: Accelerators (open access)

Muon Collider Progress: Accelerators

A muon collider would be a powerful tool for exploring the energy-frontier with leptons, and would complement the studies now under way at the LHC. Such a device would offer several important benefits. Muons, like electrons, are point particles so the full center-of-mass energy is available for particle production. Moreover, on account of their higher mass, muons give rise to very little synchrotron radiation and produce very little beamstrahlung. The first feature permits the use of a circular collider that can make efficient use of the expensive rf system and whose footprint is compatible with an existing laboratory site. The second feature leads to a relatively narrow energy spread at the collision point. Designing an accelerator complex for a muon collider is a challenging task. Firstly, the muons are produced as a tertiary beam, so a high-power proton beam and a target that can withstand it are needed to provide the required luminosity of ~1 × 10{sup 34} cm{sup –2}s{sup –1}. Secondly, the beam is initially produced with a large 6D phase space, which necessitates a scheme for reducing the muon beam emittance (“cooling”). Finally, the muon has a short lifetime so all beam manipulations must be done very rapidly. …
Date: September 10, 2011
Creator: Zisman, Michael S.
Object Type: Article
System: The UNT Digital Library
Initial-state quark energy loss from DrellYan productionin proton-proton and proton-nucleus collisions (open access)

Initial-state quark energy loss from DrellYan productionin proton-proton and proton-nucleus collisions

None
Date: January 10, 2011
Creator: Woehri, H K; Faccioli, P; Lourenco, C & Vogt, R
Object Type: Article
System: The UNT Digital Library
Sheet beam model for intense space-charge: with application to Debye screening and the distribution of particle oscillation frequencies in a thermal equilibrium beam (open access)

Sheet beam model for intense space-charge: with application to Debye screening and the distribution of particle oscillation frequencies in a thermal equilibrium beam

None
Date: January 10, 2011
Creator: Lund, S M; Bazouin, G & Friedman, A
Object Type: Article
System: The UNT Digital Library
Data-Parallel Mesh Connected Components Labeling and Analysis (open access)

Data-Parallel Mesh Connected Components Labeling and Analysis

We present a data-parallel algorithm for identifying and labeling the connected sub-meshes within a domain-decomposed 3D mesh. The identification task is challenging in a distributed-memory parallel setting because connectivity is transitive and the cells composing each sub-mesh may span many or all processors. Our algorithm employs a multi-stage application of the Union-find algorithm and a spatial partitioning scheme to efficiently merge information across processors and produce a global labeling of connected sub-meshes. Marking each vertex with its corresponding sub-mesh label allows us to isolate mesh features based on topology, enabling new analysis capabilities. We briefly discuss two specific applications of the algorithm and present results from a weak scaling study. We demonstrate the algorithm at concurrency levels up to 2197 cores and analyze meshes containing up to 68 billion cells.
Date: April 10, 2011
Creator: Harrison, Cyrus; Childs, Hank & Gaither, Kelly
Object Type: Article
System: The UNT Digital Library
Nitrate Contamination in California Groundwater: An Integrated Approach to Basin Assessment and Resource Protection (open access)

Nitrate Contamination in California Groundwater: An Integrated Approach to Basin Assessment and Resource Protection

None
Date: January 10, 2011
Creator: Esser, B. K.; Hudson, G. B.; Moran, J. E.; Beller, H.; Carlsen, T.; Dooher, B. et al.
Object Type: Report
System: The UNT Digital Library
Quantum Locality? (open access)

Quantum Locality?

Robert Griffiths has recently addressed, within the framework of a ‘consistent quantum theory’ (CQT) that he has developed, the issue of whether, as is often claimed, quantum mechanics entails a need for faster-than-light transfers of information over long distances. He argues, on the basis of his examination of certain arguments that claim to demonstrate the existence of such nonlocal influences, that such influences do not exist. However, his examination was restricted mainly to hidden-variable-based arguments that include in their premises some essentially classical-physics-type assumptions that are fundamentally incompatible with the precepts of quantum physics. One cannot logically prove properties of a system by attributing to the system properties alien to that system. Hence Griffiths’ rejection of hidden-variable-based proofs is logically warranted. Griffiths mentions the existence of a certain alternative proof that does not involve hidden variables, and that uses only macroscopically described observable properties. He notes that he had examined in his book proofs of this general kind, and concluded that they provide no evidence for nonlocal influences. But he did not examine the particular proof that he cites. An examination of that particular proof by the method specified by his ‘consistent quantum theory’ shows that the cited proof is …
Date: November 10, 2011
Creator: Stapp, Henry
Object Type: Article
System: The UNT Digital Library
Mass Market Demand Response and Variable Generation Integration Issues: A Scoping Study (open access)

Mass Market Demand Response and Variable Generation Integration Issues: A Scoping Study

This scoping study focuses on the policy issues inherent in the claims made by some Smart Grid proponents that the demand response potential of mass market customers which is enabled by widespread implementation of Advanced Metering Infrastructure (AMI) through the Smart Grid could be the “silver bullet” for mitigating variable generation integration issues. In terms of approach, we will: identify key issues associated with integrating large amounts of variable generation into the bulk power system; identify demand response opportunities made more readily available to mass market customers through widespread deployment of AMI systems and how they can affect the bulk power system; assess the extent to which these mass market Demand Response (DR) opportunities can mitigate Variable Generation (VG) integration issues in the near-term and what electricity market structures and regulatory practices could be changed to further expand the ability for DR to mitigate VG integration issues over the long term; and provide a qualitative comparison of DR and other approaches to mitigate VG integration issues.
Date: September 10, 2011
Creator: Cappers, Peter; Mills, Andrew; Goldman, Charles; Wiser, Ryan & Eto, Joseph H.
Object Type: Report
System: The UNT Digital Library
Electronic Structure of Crystalline 4He at High Pressures (open access)

Electronic Structure of Crystalline 4He at High Pressures

Using inelastic X-ray scattering techniques, we have succeeded in probing the high-pressure electronic structure of helium crystal at 300 K which has the widest known electronic energy bandgap of all materials, that was previously inaccessible to measurements due to the extreme energy and pressure range. We observed rich electron excitation spectrum, including a cut-off edge above 23 eV, a sharp exciton peak showing linear volume dependence, and a series of excitations and continuum at 26 to 45 eV. We determined electronic dispersion along the {Gamma}-M direction over two Brillouin zones, and provided a quantitative picture of the helium exciton beyond the simplified Wannier-Frenkel description.
Date: January 10, 2011
Creator: Mao, Ho Kwang; Shirley, Eric L.; Ding, Yang; Eng, Peter; Cai, Yong Q.; Chow, Paul et al.
Object Type: Article
System: The UNT Digital Library
High-Performance Language Interoperability for Scientific Computing through Babel (open access)

High-Performance Language Interoperability for Scientific Computing through Babel

None
Date: January 10, 2011
Creator: Epperly, Thomas G. W.; Kumfert, Gary; Dahlgren, Tamara; Ebner, Dietmar; Leek, Jim; Kohn, Scott et al.
Object Type: Article
System: The UNT Digital Library
Age-related changes in the plasticity and toughness of human cortical bone at multiple length-scales (open access)

Age-related changes in the plasticity and toughness of human cortical bone at multiple length-scales

The structure of human cortical bone evolves over multiple length-scales from its basic constituents of collagen and hydroxyapatite at the nanoscale to osteonal structures at nearmillimeter dimensions, which all provide the basis for its mechanical properties. To resist fracture, bone’s toughness is derived intrinsically through plasticity (e.g., fibrillar sliding) at structural-scales typically below a micron and extrinsically (i.e., during crack growth) through mechanisms (e.g., crack deflection/bridging) generated at larger structural-scales. Biological factors such as aging lead to a markedly increased fracture risk, which is often associated with an age-related loss in bone mass (bone quantity). However, we find that age-related structural changes can significantly degrade the fracture resistance (bone quality) over multiple lengthscales. Using in situ small-/wide-angle x-ray scattering/diffraction to characterize sub-micron structural changes and synchrotron x-ray computed tomography and in situ fracture-toughness measurements in the scanning electron microscope to characterize effects at micron-scales, we show how these age-related structural changes at differing size-scales degrade both the intrinsic and extrinsic toughness of bone. Specifically, we attribute the loss in toughness to increased non-enzymatic collagen cross-linking which suppresses plasticity at nanoscale dimensions and to an increased osteonal density which limits the potency of crack-bridging mechanisms at micron-scales. The link between these …
Date: August 10, 2011
Creator: Zimmermann, Elizabeth A.; Schaible, Eric; Bale, Hrishikesh; Barth, Holly D.; Tang, Simon Y.; Reichert, Peter et al.
Object Type: Article
System: The UNT Digital Library
Retrocausal Effects as a Consequence of Quantum Mechanics Refined to Accommodate the Principle of Sufficient Reason (open access)

Retrocausal Effects as a Consequence of Quantum Mechanics Refined to Accommodate the Principle of Sufficient Reason

The principle of sufficient reason asserts that anything that happens does so for a reason: no definite state of affairs can come into being unless there is a sufficient reason why that particular thing should happen. This principle is usually attributed to Leibniz, although the first recorded Western philosopher to use it was Anaximander of Miletus. The demand that nature be rational, in the sense that it be compatible with the principle of sufficient reason, conflicts with a basic feature of contemporary orthodox physical theory, namely the notion that nature's response to the probing action of an observer is determined by pure chance, and hence on the basis of absolutely no reason at all. This appeal to pure chance can be deemed to have no rational fundamental place in reason-based Western science. It is argued here, on the basis of the other basic principles of quantum physics, that in a world that conforms to the principle of sufficient reason, the usual quantum statistical rules will naturally emerge at the pragmatic level, in cases where the reason behind nature's choice of response is unknown, but that the usual statistics can become biased in an empirically manifest way when the reason for …
Date: May 10, 2011
Creator: Stapp, Henry P.
Object Type: Article
System: The UNT Digital Library
CHARACTERIZATION REPORT FOR STRONTIUM TITANATE IN SWSA 7 AND ADJACENT PARCELS IN SUPPORT OF THE NATIONAL PRIORITIES LIST SITE BOUNDARY DEFINITION PROGRAM OAK RIDGE, TENNESSEE (open access)

CHARACTERIZATION REPORT FOR STRONTIUM TITANATE IN SWSA 7 AND ADJACENT PARCELS IN SUPPORT OF THE NATIONAL PRIORITIES LIST SITE BOUNDARY DEFINITION PROGRAM OAK RIDGE, TENNESSEE

The U.S. Department of Energy (DOE) Oak Ridge Office requested support from the Oak Ridge Institute for Science and Education (ORISE) contract to delineate the extent of strontium titanate (SrTiO3) contamination in and around Solid Waste Storage Area (SWSA) 7 as part of the Oak Ridge National Priorities List Site boundary definition program. The study area is presented in Fig. 1.1 relative to the Oak Ridge Reservation (ORR). The investigation was executed according to Sampling and Analysis Plan/Quality Assurance Project Plan (SAP/QAPP) (DOE 2011) to supplement previous investigations noted below and to determine what areas, if any, have been adversely impacted by site operations.
Date: October 10, 2011
Creator: King, David A.
Object Type: Report
System: The UNT Digital Library
Data Access Performance Through Parallelization and Vectored Access: Some Results (open access)

Data Access Performance Through Parallelization and Vectored Access: Some Results

High Energy Physics data processing and analysis applications typically deal with the problem of accessing and processing data at high speed. Recent studies, development and test work have shown that the latencies due to data access can often be hidden by parallelizing them with the data processing, thus giving the ability to have applications which process remote data with a high level of efficiency. Techniques and algorithms able to reach this result have been implemented in the client side of the Scalla/xrootd system, and in this contribution we describe the results of some tests done in order to compare their performance and characteristics. These techniques, if used together with multiple streams data access, can also be effective in allowing to efficiently and transparently deal with data repositories accessible via a Wide Area Network.
Date: November 10, 2011
Creator: Furano, Fabrizio & Hanushevsky, Andrew
Object Type: Article
System: The UNT Digital Library
Extra Dimensions: 3D and Time in PDF Documentation (open access)

Extra Dimensions: 3D and Time in PDF Documentation

High energy physics is replete with multi-dimensional information which is often poorly represented by the two dimensions of presentation slides and print media. Past efforts to disseminate such information to a wider audience have failed for a number of reasons, including a lack of standards which are easy to implement and have broad support. Adobe's Portable Document Format (PDF) has in recent years become the de facto standard for secure, dependable electronic information exchange. It has done so by creating an open format, providing support for multiple platforms and being reliable and extensible. By providing support for the ECMA standard Universal 3D (U3D) file format in its free Adobe Reader software, Adobe has made it easy to distribute and interact with 3D content. By providing support for scripting and animation, temporal data can also be easily distributed to a wide audience. In this talk, we present examples of HEP applications which take advantage of this functionality. We demonstrate how 3D detector elements can be documented, using either CAD drawings or other sources such as GEANT visualizations as input. Using this technique, higher dimensional data, such as LEGO plots or time-dependent information can be included in PDF files. In principle, a …
Date: November 10, 2011
Creator: Graf, Norman A.
Object Type: Article
System: The UNT Digital Library
Processing of Non-PFP Plutonium Oxide in Hanford Plants (open access)

Processing of Non-PFP Plutonium Oxide in Hanford Plants

Processing of non-irradiated plutonium oxide, PuO2, scrap for recovery of plutonium values occurred routinely at Hanford’s Plutonium Finishing Plant (PFP) in glovebox line operations. Plutonium oxide is difficult to dissolve, particularly if it has been high-fired; i.e., calcined to temperatures above about 400°C and much of it was. Dissolution of the PuO2 in the scrap typically was performed in PFP’s Miscellaneous Treatment line using nitric acid (HNO3) containing some source of fluoride ion, F-, such as hydrofluoric acid (HF), sodium fluoride (NaF), or calcium fluoride (CaF2). The HNO3 concentration generally was 6 M or higher whereas the fluoride concentration was ~0.5 M or lower. At higher fluoride concentrations, plutonium fluoride (PuF4) would precipitate, thus limiting the plutonium dissolution. Some plutonium-bearing scrap also contained PuF4 and thus required no added fluoride. Once the plutonium scrap was dissolved, the excess fluoride was complexed with aluminum ion, Al3+, added as aluminum nitrate, Al(NO3)3•9H2O, to limit collateral damage to the process equipment by the corrosive fluoride. Aluminum nitrate also was added in low quantities in processing PuF4.
Date: March 10, 2011
Creator: Jones, Susan A. & Delegard, Calvin H.
Object Type: Report
System: The UNT Digital Library
RESULTS OF ROUTINE STRIP EFFLUENT HOLD TANK AND DECONTAMINATED SALT SOLUTION HOLD TANK SAMPLES FROM MODULAR CAUSTIC-SIDE SOLVENT EXTRACTION UNIT DURING MACROBATCH 3 OPERATIONS (open access)

RESULTS OF ROUTINE STRIP EFFLUENT HOLD TANK AND DECONTAMINATED SALT SOLUTION HOLD TANK SAMPLES FROM MODULAR CAUSTIC-SIDE SOLVENT EXTRACTION UNIT DURING MACROBATCH 3 OPERATIONS

Strip Effluent Hold Tank (SEHT) and Decontaminated Salt Solution Hold Tank (DSSHT) samples from several of the 'microbatches' of Integrated Salt Disposition Project (ISDP) Salt Batch ('Macrobatch') 3 have been analyzed for {sup 238}Pu, {sup 90}Sr, {sup 137}Cs, and by Inductively Coupled Plasma Emission Spectroscopy (ICPES). The results indicate good decontamination performance within process design expectations. While the data set is sparse, the results of this set and the previous set of results for Macrobatch 3 samples indicate consistent operations. However, the Decontamination Factors for plutonium and strontium removal have declined in Macrobatch 3, compared to Macrobatch 2. This may be due to the differences in the Pu concentration or the bulk chemical concentrations in the feed material. SRNL is considering the possible reasons for this decline. The DSSHT samples show continued presence of titanium, likely from leaching of the monosodium titanate in ARP. During operation of the ISDP, quantities of salt waste are processed through the Actinide Removal Process (ARP) and MCU in batches of {approx}3800 gallons. Monosodium titanate (MST) is used in ARP to adsorb actinides and strontium from the salt waste and the waste slurry is then filtered prior to sending the clarified salt solution to MCU. …
Date: June 10, 2011
Creator: Peters, T. & Fink, S.
Object Type: Report
System: The UNT Digital Library
HIGH-RESOLUTION ATMOSPHERIC ENSEMBLE MODELING AT SRNL (open access)

HIGH-RESOLUTION ATMOSPHERIC ENSEMBLE MODELING AT SRNL

The High-Resolution Mid-Atlantic Forecasting Ensemble (HME) is a federated effort to improve operational forecasts related to precipitation, convection and boundary layer evolution, and fire weather utilizing data and computing resources from a diverse group of cooperating institutions in order to create a mesoscale ensemble from independent members. Collaborating organizations involved in the project include universities, National Weather Service offices, and national laboratories, including the Savannah River National Laboratory (SRNL). The ensemble system is produced from an overlapping numerical weather prediction model domain and parameter subsets provided by each contributing member. The coordination, synthesis, and dissemination of the ensemble information are performed by the Renaissance Computing Institute (RENCI) at the University of North Carolina-Chapel Hill. This paper discusses background related to the HME effort, SRNL participation, and example results available from the RENCI website.
Date: May 10, 2011
Creator: Buckley, R.; Werth, D.; Chiswell, S. & Etherton, B.
Object Type: Article
System: The UNT Digital Library