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Toroidally Asymmetric Distributions of Hydrocarbon (CD) Emission and Chemical Sputtering Sources in DIII-D (open access)

Toroidally Asymmetric Distributions of Hydrocarbon (CD) Emission and Chemical Sputtering Sources in DIII-D

Measurements in DIII-D show that the carbon chemical sputtering sources along the inner divertor and center post are toroidally periodic and highest at the upstream tile edge. Imaging with a tangentially viewing camera and visible spectroscopy were used to monitor the emission from molecular hydrocarbons (CH/CD) at 430.8 nm and deuterium neutrals in attached and partially detached divertors of low-confinement mode plasmas. In contrast to the toroidally periodic CD distribution, emission from deuterium neutrals was observed to be toroidally symmetric along the inner strike zone. The toroidal distribution of the measured tile surface temperature in the inner divertor correlates with that of the CD emission, suggesting larger parallel particle and heat fluxes to the upstream tile edge, either due to toroidal tile gaps or height steps between adjacent tiles.
Date: May 16, 2006
Creator: Groth, M.; Brooks, N. H.; Fenstermacher, M. E.; Lasnier, C. J.; McLean, A. G. & Watkins, J. G.
Object Type: Article
System: The UNT Digital Library
Analytical Approach to Eigen-Emittance Evolution in Storage Rings (open access)

Analytical Approach to Eigen-Emittance Evolution in Storage Rings

This dissertation develops the subject of beam evolution in storage rings with nearly uncoupled symplectic linear dynamics. Linear coupling and dissipative/diffusive processes are treated perturbatively. The beam distribution is assumed Gaussian and a function of the invariants. The development requires two pieces: the global invariants and the local stochastic processes which change the emittances, or averages of the invariants. A map based perturbation theory is described, providing explicit expressions for the invariants near each linear resonance, where small perturbations can have a large effect. Emittance evolution is determined by the damping and diffusion coefficients. The discussion is divided into the cases of uniform and non-uniform stochasticity, synchrotron radiation an example of the former and intrabeam scattering the latter. For the uniform case, the beam dynamics is captured by a global diffusion coefficient and damping decrement for each eigen-invariant. Explicit expressions for these quantities near coupling resonances are given. In many cases, they are simply related to the uncoupled values. Near a sum resonance, it is found that one of the damping decrements becomes negative, indicating an anti-damping instability. The formalism is applied to a number of examples, including synchrobetatron coupling caused by a crab cavity, a case of current interest …
Date: May 16, 2006
Creator: Nash, Boaz
Object Type: Report
System: The UNT Digital Library
Simulations of liquid ribidium expanded to the critical density (open access)

Simulations of liquid ribidium expanded to the critical density

Quantum molecular dynamic simulations were used to examine the change in atomic and electronic structure in liquid rubidium along its liquid-vapor coexistence curve. Starting from the liquid at the triple point, with increasing expansion we observe a continuous increase in the electron localization leading to ion clustering near the metal-nonmetal transition at about twice the critical density, in agreement with electrical measurements, and to the presence of dimers near and below the critical density.
Date: May 16, 2006
Creator: Ross, M; Yang, L H & Pilgrim, W
Object Type: Article
System: The UNT Digital Library
Status And Prospects of the BaBar SVT (open access)

Status And Prospects of the BaBar SVT

The BABAR Silicon Vertex Tracker (SVT) has been efficiently operated for five years since the start of data taking in 1999. It has met design requirements and no degradation in its performance has been observed thus far. However, because of higher than expected background levels, and anticipated further increases in luminosity and dose rates, we have done a thorough study to assess the viability of operating the SVT until the end of the decade.
Date: May 16, 2006
Creator: Re, V.; Bruinsma, M.; Curry, S.; Kirkby, D.; Berryhill, J.; Burke, S. et al.
Object Type: Article
System: The UNT Digital Library
Electronics for Satellite Experiments (open access)

Electronics for Satellite Experiments

The tracking detector for the LAT science instrument on the GLAST mission is an example of a large-scale particle detection system built primarily by particle physicists for space flight within the context of a NASA program. The design and fabrication model in most ways reflected practice and experience from particle physics, but the quality assurance aspects were guided by NASA. Similarly, most of the electronics in the LAT as a whole were designed and built by staff at a particle physics lab. This paper reports on many of the challenges and lessons learned in the experience of designing and building the tracking detector and general LAT electronics for use in the NASA GLAST mission.
Date: May 16, 2006
Creator: Johnson, Robert P. & /UC, Santa Cruz
Object Type: Article
System: The UNT Digital Library
Feasibility of Diffraction Radiation for a Non-invasive Diagnostics of the SLAC Electron Beam (open access)

Feasibility of Diffraction Radiation for a Non-invasive Diagnostics of the SLAC Electron Beam

The development of the non-invasive bunch size diagnostics based on the diffraction radiation is now in progress in frame of TPU-KEK-SLAC collaboration. The experimental test of a transverse beam size measurement was performed successful on the KEK-ATF extracted electron beam. However many difficulties emerge if we going from the one GeV electron energy to the several tenth GeV electron beams. The extremely high Lorenz-factor value gives rise to the some problems, such as large contribution of a radiation from an accelerator construction elements in submillimeter wavelength region, extremely pre-wave zone effect even in the optical range, exceeding of the electron beam divergence over the diffraction radiation cone, and so on. More over, the sensitivity of the method based on the optical diffraction radiation from flat slit target decrease catastrophic when an electron energy increase up to several tenth GeV. We suggest the new method based on the phase shift on the slit target, consisting on the two semi-planes which are turned at a some angle one to other (crossed target technique) and present here the results of experimental test of this technique. Also we discuss the origins of indicated difficulties and suggest the ways of these problems solution.
Date: May 16, 2006
Creator: Naumenko, G.; Potylitsyn, A.; U., /Tomsk Polytechnic; Araki, S.; Aryshev, A.; Hayano, H. et al.
Object Type: Article
System: The UNT Digital Library
Performances of Induction System for Nanosecond Mode Operation (open access)

Performances of Induction System for Nanosecond Mode Operation

An induction system comprises an array of single turn pulse transformers. Ferromagnetic cores of transformers are toroids that are stacked along the longitudinal core axis. Another name for this array is a fraction transformer or an adder. The primary and secondary windings of such a design have one turn. The step up mode is based on the number of primary pulse sources. The secondary windings are connected in series. Performances of such a system for the nanosecond range mode operation are different in comparison to the performances of traditional multi-turn pulse transformers, which are working on a 100+ nanosecond mode operation. In this paper, the author discusses which aspects are necessary to take into account for the high power nanosecond fractional transformer designs. The engineering method of the nanosecond induction system design is presented.
Date: May 16, 2006
Creator: Krasnykh, Anatoly
Object Type: Article
System: The UNT Digital Library
Greensheet (Houston, Tex.), Vol. 37, No. 170, Ed. 1 Tuesday, May 16, 2006 (open access)

Greensheet (Houston, Tex.), Vol. 37, No. 170, Ed. 1 Tuesday, May 16, 2006

Free weekly newspaper that includes business and classified advertising.
Date: May 16, 2006
Creator: unknown
Object Type: Newspaper
System: The Portal to Texas History
The U.S. Trade Deficit: Causes, Consequences, and Cures (open access)

The U.S. Trade Deficit: Causes, Consequences, and Cures

None
Date: May 16, 2006
Creator: unknown
Object Type: Report
System: The UNT Digital Library
[Email from Shannon Bailey to multiple recipients about TSDC dues] (open access)

[Email from Shannon Bailey to multiple recipients about TSDC dues]

Email from Shannon Bailey to multiple recipients on May 16, 2006, discussing Texas Stonewall Democratic Caucus dues and lists.
Date: May 16, 2006
Creator: unknown
Object Type: Text
System: The UNT Digital Library
Seismic Safety Study (open access)

Seismic Safety Study

During the past three decades, the Laboratory has been proactive in providing a seismically safe working environment for its employees and the general public. Completed seismic upgrades during this period have exceeded $30M with over 24 buildings structurally upgraded. Nevertheless, seismic questions still frequently arise regarding the safety of existing buildings. To address these issues, a comprehensive study was undertaken to develop an improved understanding of the seismic integrity of the Laboratory's entire building inventory at the Livermore Main Site and Site 300. The completed study of February 2005 extended the results from the 1998 seismic safety study per Presidential Executive Order 12941, which required each federal agency to develop an inventory of its buildings and to estimate the cost of mitigating unacceptable seismic risks. Degenkolb Engineers, who performed the first study, was recontracted to perform structural evaluations, rank order the buildings based on their level of seismic deficiencies, and to develop conceptual rehabilitation schemes for the most seriously deficient buildings. Their evaluation is based on screening procedures and guidelines as established by the Interagency Committee on Seismic Safety in Construction (ICSSC). Currently, there is an inventory of 635 buildings in the Laboratory's Facility Information Management System's (FIMS's) database, out …
Date: May 16, 2006
Creator: Tokarz, F J & Coats, D W
Object Type: Report
System: The UNT Digital Library
Supporting National User Communities at NERSC and NCAR (open access)

Supporting National User Communities at NERSC and NCAR

The National Energy Research Scientific Computing Center(NERSC) and the National Center for Atmospheric Research (NCAR) are twocomputing centers that have traditionally supported large national usercommunities. Both centers have developed responsive approaches to supportthese user communities and their changing needs, providing end-to-endcomputing solutions. In this report we provide a short overview of thestrategies used at our centers in supporting our scientific users, withan emphasis on some examples of effective programs and futureneeds.
Date: May 16, 2006
Creator: Killeen, Timothy L. & Simon, Horst D.
Object Type: Article
System: The UNT Digital Library

Renewable Electrolysis Integrated System Development and Testing

None
Date: May 16, 2006
Creator: Kroposki, B.
Object Type: Presentation
System: The UNT Digital Library
Science with Micro-X: the TES Microcalorimeter X-ray Imaging Rocket (open access)

Science with Micro-X: the TES Microcalorimeter X-ray Imaging Rocket

Micro-X is a proposed sounding rocket experiment that will combine a transition-edge-sensor X-ray-microcalorimeter array with a conical imaging mirror to obtain high-spectral-resolution images of extended and point X-ray sources. We describe the payload and the science targeted by this mission including the discussion of three possible Micro-X targets: the Puppis A supernova remnant, the Virgo Cluster, and Circinus X-1. For example, a Micro-X observation of the bright eastern knot of Puppis A will obtain a line-dominated spectrum with 90,000 counts collected in 300 seconds at 2 eV resolution across the 0.3-2.5 keV band. Micro-X will utilize plasma diagnostics to determine the thermodynamic and ionization state of the plasma, to search for line shifts and broadening associated with dynamical processes, and seek evidence of ejecta enhancement. For clusters of galaxies, Micro-X can uniquely study turbulence and the temperature distribution function. For binaries, Micro-X's high resolution spectra will separate the different processes contributing to the Fe K lines at 6 keV and give a clear view of the geometry of the gas flows and circumstellar gas.
Date: May 16, 2006
Creator: Figueroa-Feliciano, E; Bandler, S R; Bautz, M; Boyce, K R; Brown, G V; Deiker, S et al.
Object Type: Article
System: The UNT Digital Library
ISOPAR L RELEASE FROM SALTSTONE CURED AT 55 C (open access)

ISOPAR L RELEASE FROM SALTSTONE CURED AT 55 C

The decontaminated salt solution waste stream from the Modular Caustic Side Solvent Extraction Unit and the Salt Waste Processing Facility is anticipated to contain entrained extraction solvent. The decontaminated salt solution is scheduled to be processed through Tank 50 into the Saltstone Production Facility. This study, among others, has been undertaken because the solvent concentration in the decontaminated salt solution may cause flammability issues within the Saltstone Disposal Facility that may need to be addressed prior to operation. Previous work at the Savannah River National Laboratory determined the release of Isopar{reg_sign} L from saltstone prepared with a simulated DSS with Isopar{reg_sign} L concentrations ranging from 50 to 200 {micro}g/g in the salt fraction and with test temperatures ranging from ambient to 95 C. The results from the curing of the saltstone showed that the Isopar{reg_sign} L release data can be treated as a percentage of initial concentration in the concentration range studied. The majority of the Isopar{reg_sign} L that was released over the test duration was released in the first few days. The release of Isopar{reg_sign} L begins immediately and the rate of release decreases over time. At higher temperatures the immediate release is larger than at lower temperatures. In …
Date: May 16, 2006
Creator: Cozzi, A; Cora Berry, C; Michael Bronikowski, M; Russell Eibling, R & Jack Zamecnik, J
Object Type: Report
System: The UNT Digital Library
Search for Gamma-rays from Lightest Kaluza-Klein ParticleDark Matter with GLAST (open access)

Search for Gamma-rays from Lightest Kaluza-Klein ParticleDark Matter with GLAST

The Gamma-Ray Large Area Space Telescope (GLAST), scheduled to be launched in 2007, is the next generation satellite for high-energy gamma-ray astronomy. The Large Area Telescope (LAT), GLAST main instrument, has a wide field of view (> 2 sr), a large effective area and a 20 MeV-300 GeV energy range. It provides excellent high-energy gamma-ray observations for Dark-Matter searches. Here we study the possibility to detect gamma-rays coming from Lightest Kaluza-Klein Particle (LKP) annihilations in the context of the minimal Universal Extra Dimensions (UED) models. We perform the analysis for different LKP masses and for a Galactic Center (GC) Navarro, Frenk and White (NFW) halo model modified by a boost factor parameter. Finally we give an estimate of the background to obtain the expected total gamma-ray flux and the corresponding expected GLAST sensitivity.
Date: May 16, 2006
Creator: Nuss, E.; Cohen-Tanugi, J.; Lionetto, A. & /Montpellier U. /SLAC /Rome U.,Tor Vergata
Object Type: Article
System: The UNT Digital Library
NNLL QCD Contribution of the Electromagentic Dipole Operator to \bar B --> X_s gamma (open access)

NNLL QCD Contribution of the Electromagentic Dipole Operator to \bar B --> X_s gamma

We present an independent calculation of that part of the O({alpha}{sub s}{sup 2}) contribution to dipole operator {Omicron}{sub 7}. Using a different method, we find complete agreement mass ambiguity appearing at NLL accuracy. the complete NNLL prediction of {Lambda}({bar B} {yields} X{sub s}{gamma}) which will resolve the charm quark the decay width {Lambda}({bar B} {yields} X{sub s}{gamma}) which arises from the self-interference term of the electromagnetic with a previous calculation. This NNLL contribution is an important ingredient for
Date: May 16, 2006
Creator: Asatrian, H.M.; Hovhannisyan, A.; Poghosyan, V.; Inst., /Yerevan Phys.; Ewerth, T.; Greub, C. et al.
Object Type: Article
System: The UNT Digital Library
A Guide for Using the Transient Ground-Water Flow Model of the Death Valley Regional Ground-Water Flow System, Nevada and California (open access)

A Guide for Using the Transient Ground-Water Flow Model of the Death Valley Regional Ground-Water Flow System, Nevada and California

This report is a guide for executing numerical simulations with the transient ground-water flow model of the Death Valley regional ground-water flow system, Nevada and California using the U.S. Geological Survey modular finite-difference ground-water flow model, MODFLOW-2000. Model inputs, including observations of hydraulic head, discharge, and boundary flows, are summarized. Modification of the DVRFS transient ground-water model is discussed for two common uses of the Death Valley regional ground-water flow system model: predictive pumping scenarios that extend beyond the end of the model simulation period (1998), and model simulations with only steady-state conditions.
Date: May 16, 2006
Creator: Blainey, Joan B. & Claudia C. Faunt, and Mary C. Hill
Object Type: Report
System: The UNT Digital Library
On-Site Generation Simulation with EnergyPlus for CommercialBuildings (open access)

On-Site Generation Simulation with EnergyPlus for CommercialBuildings

Building energy simulation software (e.g., EnergyPlus) is apowerful tool used widely by designers and researchers. However, currentsoftware is limited in modeling distributed generation (DG), including DGwith heat recovery applied to building end-use, i.e., combined heat andpower (CHP). Concurrently, DG investment and dispatch optimizationsoftware has been developed, yet has not been linked to a building energysimulation program for accurate assessment of DG designs, particularlyunder uncertainty in future end-use loads and equipment availability. CHPis a proven approach to cost effective reductions in primary fuelconsumption and CO2 emissions. Integrating DG system design and controlsinto building energy simulation is an important step towards popular DGacceptance. We propose to extend the existing building energy simulationprogram, EnergyPlus (E+), to enable the simulation of various DG modulesand associated control strategies in order to achieve more accurate andholistic analysis of DG technologies. Extension of EnergyPlus isconveniently facilitated by SPARK, a program capable of modeling buildingequipment and controls as individual modules. These modules can beautomatically integrated with EnergyPlus building models. Candidate DGsystems can be selected from the DG investment optimization program,Distributed Energy Resources Customer Adoption Model (DER-CAM). Thedispatch of the modeled DG system can be determined by a novel dispatchoptimization algorithm, the Energy Manager, that accounts for uncertaintyin future …
Date: May 16, 2006
Creator: Stadler, Michael; Firestone, Ryan; Curtil, Dimitri & Marnay, Chris
Object Type: Article
System: The UNT Digital Library
In Situ Adsorption Studies at the Solid/Liquid Interface:Characterization of Biological Surfaces and Interfaces Using SumFrequency Generation Vibrational Spectroscopy, Atomic Force Microscopy,and Quartz Crystal Microbalance (open access)

In Situ Adsorption Studies at the Solid/Liquid Interface:Characterization of Biological Surfaces and Interfaces Using SumFrequency Generation Vibrational Spectroscopy, Atomic Force Microscopy,and Quartz Crystal Microbalance

Sum frequency generation (SFG) vibrational spectroscopy, atomic force microscopy (AFM), and quartz crystal microbalance (QCM) have been used to study the molecular surface structure, surface topography and mechanical properties, and quantitative adsorbed amount of biological molecules at the solid-liquid interface. The molecular-level behavior of designed peptides adsorbed on hydrophobic polystyrene and hydrophilic silica substrates has been examined as a model of protein adsorption on polymeric biomaterial surfaces. Proteins are such large and complex molecules that it is difficult to identify the features in their structure that lead to adsorption and interaction with solid surfaces. Designed peptides which possess secondary structure provide simple model systems for understanding protein adsorption. Depending on the amino acid sequence of a peptide, different secondary structures ({alpha}-helix and {beta}-sheet) can be induced at apolar (air/liquid or air/solid) interfaces. Having a well-defined secondary structure allows experiments to be carried out under controlled conditions, where it is possible to investigate the affects of peptide amino acid sequence and chain length, concentration, buffering effects, etc. on adsorbed peptide structure. The experiments presented in this dissertation demonstrate that SFG vibrational spectroscopy can be used to directly probe the interaction of adsorbing biomolecules with a surface or interface. The use of …
Date: May 16, 2006
Creator: Phillips, Diana Christine
Object Type: Thesis or Dissertation
System: The UNT Digital Library
China-U.S. Trade Issues (open access)

China-U.S. Trade Issues

This report details the information related to U.S trade with China and the major U.S - China trade issues.
Date: May 16, 2006
Creator: Morrison, Wayne M.
Object Type: Report
System: The UNT Digital Library
Interior, Environment, and Related Agencies: FY2007 Appropriations (open access)

Interior, Environment, and Related Agencies: FY2007 Appropriations

None
Date: May 16, 2006
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Arctic National Wildlife Refuge (ANWR): Controversies for the 109th Congress (open access)

Arctic National Wildlife Refuge (ANWR): Controversies for the 109th Congress

This report provides information about Arctic National Wildlife Refuge (ANWR) and controversies for the 109th congress.
Date: May 16, 2006
Creator: Corn, M. Lynne; Gelb, Bernald A. & Baldwin, Pamela
Object Type: Report
System: The UNT Digital Library
Model of CSR Induced Bursts in Slicing Experiments (open access)

Model of CSR Induced Bursts in Slicing Experiments

We suggest a model describing the CSR bursts observed in recent experiments at the Advanced Light Source at the LBL. The model is based on the linear theory of the CSR instability in electron rings. We describe how an initial perturbation of the beam generated by the laser pulse evolves in time when the beam is unstable due to the CSR wakefield.
Date: May 16, 2006
Creator: Stupakov, G. & Heifets, S.
Object Type: Article
System: The UNT Digital Library