X-Ray Backlighting for the National Ignition Facility (open access)

X-Ray Backlighting for the National Ignition Facility

X-ray backlighting is a powerful tool for diagnosing a large variety of high-energy-density phenomena. Traditional area backlighting techniques used at Nova and Omega cannot be extended efficiently to NIF-scale. New, more efficient backlighting sources and techniques are required and have begun to show promising results. These include a backlit-pinhole point projection technique, pinhole and slit arrays, distributed polychromatic sources, and picket fence backlighters. In parallel, there have been developments in improving the data SNR and hence quality by switching from film to CCD-based recording media and by removing the fixed-pattern noise of MCP-based cameras.
Date: July 25, 2000
Creator: Landen, O. L.; Farley, D. R.; Glendinning, S. G.; Logory, E. M.; Bell, P. M.; Koch, J. A. et al.
Object Type: Article
System: The UNT Digital Library
Sound Speeds of Post-Failure Wave Glass (open access)

Sound Speeds of Post-Failure Wave Glass

Plate impact experiments were performed on B270 glass in order to measure the properties of post-failure wave material. The initial failure wave velocity is 1.27 km/s . After the material is released, the failure wave velocity drops to 0.65 km/s. At a stress of 6.72 GPa, the sound speed in the failed material is 4.97 km/s (compare to 5.79 km/s in the intact material) with a density comparable to the predicted shock value. At a stress of 0.26 GPa, the average sound speed in the failed material is 3.55 km/s, and the density drops to 65% of the intact value. The spall strength of the failed material is greater than 0.14 GPa.
Date: July 25, 2000
Creator: Cazamias, J U; Fiske, P S & Bless, S J
Object Type: Article
System: The UNT Digital Library
REMARKS ON THE MAXIMUM ENTROPY METHOD APPLIED TO FINITE TEMPERATURE LATTICE QCD. (open access)

REMARKS ON THE MAXIMUM ENTROPY METHOD APPLIED TO FINITE TEMPERATURE LATTICE QCD.

We make remarks on the Maximum Entropy Method (MEM) for studies of the spectral function of hadronic correlators in finite temperature lattice QCD. We discuss the virtues and subtlety of MEM in the cases that one does not have enough number of data points such as at finite temperature. Taking these points into account, we suggest several tests which one should examine to keep the reliability for the results, and also apply them using mock and lattice QCD data.
Date: July 25, 2005
Creator: Umeda, T. & Matsufuru, H.
Object Type: Article
System: The UNT Digital Library
Isospin Breaking and the Chiral Condensate. (open access)

Isospin Breaking and the Chiral Condensate.

With two degenerate quarks, the chiral condensate exhibits a jump as the quark masses pass through zero. I discuss how this single transition splits into two Ising like transitions when the quarks are made non-degenerate. The order parameter is the expectation of the neutral pion field. The transitions represent long distance coherent phenomena occurring without the Dirac operator having vanishingly small eigenvalues.
Date: July 25, 2005
Creator: Creutz, M.
Object Type: Article
System: The UNT Digital Library
Simulation of Time-Reversal Processing for Electromagnetic Communication (open access)

Simulation of Time-Reversal Processing for Electromagnetic Communication

Time-reversal processing was simulated for several possible electromagnetic communication channels, including random point scatterers, large plates and a conducting cavity. Communication was from a single transmitting antenna to a receiving array. The effectiveness of time-reversal processing was compared for a single receiver and the array. The aim of these simulations was to determine a communication environment that would give an interesting level of multipath interference and that can be constructed in a laboratory.
Date: July 25, 2003
Creator: Burke, G J & Poggio, A J
Object Type: Report
System: The UNT Digital Library
Nuclear Energy Research Initiative Program (NERI) Quarterly Progress Report - New Design Equations for Swelling and Irradiation Creep in Generation IV Reactors (open access)

Nuclear Energy Research Initiative Program (NERI) Quarterly Progress Report - New Design Equations for Swelling and Irradiation Creep in Generation IV Reactors

None
Date: July 25, 2003
Creator: Surh, M P & Wolfer, W G
Object Type: Report
System: The UNT Digital Library
Scoping Inventory Calculations for the Rare Isotope Accelerator (open access)

Scoping Inventory Calculations for the Rare Isotope Accelerator

This document is a report on our activities in FY03 exploring nuclear safety and hazard analysis issues relevant to the Rare Isotope Accelerator (RIA). It is not clear whether DOE will classify the RIA as an accelerator facility subject to the accelerator-specific safety requirements of DOE Order 420.2A or as a nonreactor nuclear facility subject to the requirements of 10 CFR 830. The final outcome of this issue will have significant impact on the construction and operation of the facility and the quality assurance requirements for items or services that may affect nuclear safety. The resolution of this issue will be an important earlier decision for the RIA project team and will require early consultation with the appropriate DOE authorities. For nuclear facilities, facility hazard classification depends on the inventory of releasable radionuclides; therefore, some simplistic, scoping inventory calculations for some assumed targets and beams are done to estimate the hazard category of RIA if it is declared a nuclear facility. These calculations show that for the scenarios analyzed, RIA would produce sufficient quantities of radionuclides to be classified as a Category 3 nuclear facility. Over the lifetime of RIA operations, it may be possible to build up Category 2 …
Date: July 25, 2003
Creator: Ahle, L. E. & Boles, J. L.
Object Type: Report
System: The UNT Digital Library
Nuclear Energy Research Initiative Program (NERI) Quarterly Progress Report - New Design Equations for Swelling and Irradiation Creep in Generation IV Reactors (open access)

Nuclear Energy Research Initiative Program (NERI) Quarterly Progress Report - New Design Equations for Swelling and Irradiation Creep in Generation IV Reactors

None
Date: July 25, 2003
Creator: Surh, M P & Wolfer, W G
Object Type: Report
System: The UNT Digital Library
Recent Results from the Low Temperature Spare Astro-E Microcalorimeter Used at the LLNL EBIT-I and EBIT-II (open access)

Recent Results from the Low Temperature Spare Astro-E Microcalorimeter Used at the LLNL EBIT-I and EBIT-II

In the past year a spare NASA/GSFC Astro-E microcalorimeter has been installed, tested, and run successfully on the electron beam ions traps EBIT-I and EBIT-II at the Lawrence Livermore National Laboratory. The microcalorimeter complements crystal and grating spectrometers already part of the LLNL ebit program making it possible to measure a broad bandwidth ({approx}0.3-10 keV) with moderate resolution while simultaneously measuring a narrow bandwidth ({approx}0.7-1.3 keV) with high resolution. An overview of recent work, including measurements by the microcalorimeter of absolute excitation cross is presented. These results continue our effort to provide atomic data of high quality to be used as benchmarks of theoretical calculations and to be included in atomic data bases employed by spectral fitting packages used to interpret spectra obtained by XMM-Newton and the Chandra X-Ray Observatory.
Date: July 25, 2001
Creator: Brown, G V; Behar, E; Beiersdorfer, P; Boyce, K R; Chen, H; Gendreau, K C et al.
Object Type: Article
System: The UNT Digital Library
The Pepcon Disaster-Causative Factors and potential Preventive and Mitigative Measures (open access)

The Pepcon Disaster-Causative Factors and potential Preventive and Mitigative Measures

On May 4, 1988, the PEPCON plant experienced three major and several smaller explosions that caused over $70 million in property damage and caused two deaths. The PEPCON plant produced Ammonium Perchlorate (AP), a major ingredient for rocket fuel. The PEPCON plant and the nearby Kidd Marshmallow plant were totally destroyed by the detonations. The initiating event for the explosions was a fire that originated in the Batch Dryer Building and spread to adjacent storage. Several factors combined to cause the AP in the major storage fields to detonate, the most important being lack of adequate separation between storage units. Welding and flame cutting procedure with poor fire watch protocol was the prime candidate for fire ignition. There were no automatic fire suppression systems at the plant. Buildings including the Batch Dryer Building were made of combustible building material (fiberglass). There was poor housekeeping and no control of AP dust generation. AP was stored in combustible polyethylene drums, aluminum tote bins, 30-gallon steel storage drums and fiber reinforced tote bags. There were high-density storage practices. In addition, a contributing factor to the rapid fire-spread was that the wind that day was blowing directly from the batch dryer building to the …
Date: July 25, 2003
Creator: Lambert, H E & Alvares, N J
Object Type: Article
System: The UNT Digital Library
RCRA Groundwater Quality Assessment Report for Single-Shell Tank Waste Management Area T (January 1998 through December 2001) (open access)

RCRA Groundwater Quality Assessment Report for Single-Shell Tank Waste Management Area T (January 1998 through December 2001)

This report presents the findings of continued groundwater quality assessment at Waste Management Area T in the 200 West Area of the Hanford Site. It covers January 1988 through December 2001.
Date: July 25, 2002
Creator: Horton, Duane G.; Hodges, Floyd N.; Johnson, V. G. & Chou, Charissa J.
Object Type: Report
System: The UNT Digital Library
Final Implementation Report for the National Defense Authorization Act for Fiscal Year 2008 (open access)

Final Implementation Report for the National Defense Authorization Act for Fiscal Year 2008

This report on the implementation of National Defense Authorization Act (NDAA) for Fiscal Year 2008, section 904 "Management of the Department of Defense," presents the consensus recommendations of the Department's senior management team on the assignment of duties for the Chief Management Office (CMO), the Deputy Chief Management Office, and the Military Department CMO's, as well as summarizing the Department's inaugural Strategic Management Plan.
Date: July 25, 2008
Creator: United States. Department of Defense.
Object Type: Report
System: The UNT Digital Library
Science to Support DOE Site Cleanup: The Pacific Northwest National Laboratory Environmental Management Science Program Awards - Fiscal Year 2000 Mid-Year Progress Report (open access)

Science to Support DOE Site Cleanup: The Pacific Northwest National Laboratory Environmental Management Science Program Awards - Fiscal Year 2000 Mid-Year Progress Report

Pacific Northwest National Laboratory was awarded ten Environmental Management Science Program (EMSP) research grants in fiscal year 1996, six in fiscal year 1997, eight in fiscal year 1998 and seven in fiscal year 1999.(a) All of the fiscal year 1996 awards have been completed and the Principal Investigators are writing final reports, so their summaries will not be included in this document. This section summarizes how each of the currently funded grants addresses significant U.S. Department of Energy (DOE) cleanup issues, including those at the Hanford Site. The technical progress made to date in each of these research projects is addressed in more detail in the individual progress reports contained in this document. This research performed at PNNL is focused primarily in four areas: Tank Waste Remediation, Decontamination and Decommissioning, Spent Nuclear Fuel and Nuclear Materials, and Soil and Groundwater Cleanup.
Date: July 25, 2000
Creator: Carlson, Clark D. & Bennett, Sheila Q.
Object Type: Report
System: The UNT Digital Library
Sunyaev-Zel'Dovich effect observations of the bullet cluster (1E 0657-56) with APEX-SZ (open access)

Sunyaev-Zel'Dovich effect observations of the bullet cluster (1E 0657-56) with APEX-SZ

We present observations of the Sunyaev-Zel'dovich effect (SZE) in the Bullet cluster (1E 0657-56) using the APEX-SZ instrument at 150 GHz with a resolution of 1'. The main results are maps of the SZE in this massive, merging galaxy cluster. The cluster is detected with 23 sigma significance within the central 1' radius of the source position. The SZE map has a broadly similar morphology to that in existing X-ray maps of this system, and we find no evidence for significant contamination of the SZE emission by radio or IR sources. In order to make simple quantitative comparisons with cluster gas models derived from X-ray observations, we fit our data to an isothermal elliptical beta model, despite the inadequacy of such a model for this complex merging system. With an X-ray derived prior on the power-law index, beta = 1.04+0.16-0.10, we find a core radius rc = 142" +- 18", an axial ratio of 0.889 +- 0.072, and a central temperature decrement of -771 +- 71 muKCMB, including a +-5.5percent flux calibration uncertainty. Combining the APEX-SZ map with a map of projected electron surface density from Chandra X-ray observations, we determine the mass-weighted temperature of the cluster gas to be …
Date: July 25, 2008
Creator: Halverson, N. W.; Lanting, T.; Ade, P. A. R.; Basu, K.; Bender, A. N.; Benson, B. A. et al.
Object Type: Article
System: The UNT Digital Library
Improving chiral property of domain-wall fermions by reweighting method (open access)

Improving chiral property of domain-wall fermions by reweighting method

The reweighting method is applied to improve the chiral property of domain-wall fermions. One way to achieve this is to enlarge L{sub s}, the size of fifth dimension, which controls the size of the induced chiral symmetry breaking. While this is a type of reweighting method for shifting the action parameter, it seems non-trivial since this reweighting means change of the five dimensional lattice volume. In this report, we address issues in this direction of reweighting and evaluate its effectiveness.
Date: July 25, 2009
Creator: Ishikawa, T.; Aoki, Y. & Izubuchi, T.
Object Type: Article
System: The UNT Digital Library
Initial Results from the Lost Alpha Diagnostics on Joint European Torus (open access)

Initial Results from the Lost Alpha Diagnostics on Joint European Torus

Two devices have been installed in the Joint European Torus (JET) vacuum vessel near the plasma boundary to investigate the loss of energetic ions and fusion products in general and alpha particles in particular during the upcoming JET experiments. These devices are (i) a set of multichannel thin foil Faraday collectors, and (ii) a well collimated scintillator which is optically connected to a charge-coupled device. Initial results, including the radial energy and poloidal dependence of lost ions from hydrogen and deuterium plasmas during the 2005–06 JET restart campaign, will be presented.
Date: July 25, 2007
Creator: Darrow, Doug; Cecil, Ed; Ellis, Bob; Fullard, Keith; Hill, Ken; Horton, Alan et al.
Object Type: Report
System: The UNT Digital Library
Evaluation of the Dallas Thompson Riverscreen Site on the Touchet River. (open access)

Evaluation of the Dallas Thompson Riverscreen Site on the Touchet River.

Riverscreen irrigation pumps are a relatively new design in which the pump intake floats on the river surface, pulling water in only from the bottom side and surrounded by a self-cleaning screen. The Walla Walla County Conservation District recently started replacing old pump screens with the Riverscreen and was interested in whether the screens are protective of juvenile salmonids. Pacific Northwest National Laboratory evaluated approach velocities and operations at the Riverscreen installation on the Dallas Thompson property, approximately 3 mi. north of Touchet, Washington and 300 ft north of Hofer Dam, on June 18, 2007. Evaluation of this site consisted of underwater videography and water velocity measurements. The Dallas Thompson Riverscreen was pumping approximately 930 gpm during our evaluation, which is close to the maximum pumping rate for this model. Underwater videography showed only slow movement of water-borne particulates toward the pump intake, and the screen material was clean. All water velocity measurements were taken below the pump intake opening and between 3 to 6 in. from the screen face. All approach velocities (flow toward the screen and pump) were below National Marine Fisheries Service draft guidelines for juvenile fish screens.
Date: July 25, 2007
Creator: Chamness, Mickie
Object Type: Report
System: The UNT Digital Library
Light-Front Holography and Hadronization at the Amplitude Level (open access)

Light-Front Holography and Hadronization at the Amplitude Level

The correspondence between theories in anti-de Sitter space and conformal field theories in physical space-time leads to an analytic, semiclassical model for strongly-coupled QCD which has scale invariance at short distances and color confinement at large distances. Light-front holography is a remarkable feature of AdS/CFT: it allows hadronic amplitudes in the AdS fifth dimension to be mapped to frame-independent light-front wavefunctions of hadrons in physical space-time, thus providing a relativistic description of hadrons at the amplitude level. Some novel features of QCD are discussed, including the consequences of confinement for quark and gluon condensates and the behavior of the QCD coupling in the infrared. We suggest that the spatial support of QCD condensates is restricted to the interior of hadrons, since they arise due to the interactions of confined quarks and gluons. Chiral symmetry is thus broken in a limited domain of size 1=m{sub {pi}} in analogy to the limited physical extent of superconductor phases. A new method for computing the hadronization of quark and gluon jets at the amplitude level, an event amplitude generator, is outlined.
Date: July 25, 2008
Creator: Brodsky, Stanley J.; de Teramond, Guy & Shrock, Robert
Object Type: Article
System: The UNT Digital Library
DEFENSE WASTE PROCESSING FACILITY ANALYTICAL METHOD VERIFICATION FOR THE SLUDGE BATCH 5 QUALIFICATION SAMPLE (open access)

DEFENSE WASTE PROCESSING FACILITY ANALYTICAL METHOD VERIFICATION FOR THE SLUDGE BATCH 5 QUALIFICATION SAMPLE

For each sludge batch that is processed in the Defense Waste Processing Facility (DWPF), the Savannah River National Laboratory (SRNL) performs confirmation of the applicability of the digestion method to be used by the DWPF lab for elemental analysis of Sludge Receipt and Adjustment Tank (SRAT) receipt samples and SRAT product process control samples. DWPF SRAT samples are typically dissolved using a room temperature HF-HNO3 acid dissolution (i.e., DWPF Cold Chem Method, see Procedure SW4-15.201) and then analyzed by inductively coupled plasma - atomic emission spectroscopy (ICP-AES). This report contains the results and comparison of data generated from performing the Aqua Regia (AR), Sodium Peroxide/Hydroxide Fusion (PF) and DWPF Cold Chem (CC) method digestion of Sludge Batch 5 (SB5) SRAT Receipt and SB5 SRAT Product samples. The SB5 SRAT Receipt and SB5 SRAT Product samples were prepared in the SRNL Shielded Cells, and the SRAT Receipt material is representative of the sludge that constitutes the SB5 Batch composition. This is the sludge in Tank 51 that is to be transferred into Tank 40, which will contain the heel of Sludge Batch 4 (SB4), to form the SB5 Blend composition. The results for any one particular element should not be used …
Date: July 25, 2008
Creator: Click, D; Tommy Edwards, T & Henry Ajo, H
Object Type: Report
System: The UNT Digital Library
Neutron Soft Errors in Xilinx FPGAs at Lawrence Berkeley National Laboratory (open access)

Neutron Soft Errors in Xilinx FPGAs at Lawrence Berkeley National Laboratory

The LBNL 88-Inch Cyclotron offers broad-spectrum neutrons for single event effects testing. We discuss results from this beamline for neutron soft upsets in Xilinx Virtex-4 and -5 field-programmable-gate-array (FPGA) devices.
Date: July 25, 2008
Creator: George, Jeffrey S.; Koga, Rocky & McMahan, Margaret A.
Object Type: Article
System: The UNT Digital Library
Executive Summary of the Workshop on Polarization and Beam Energy Measurements at the ILC (open access)

Executive Summary of the Workshop on Polarization and Beam Energy Measurements at the ILC

This note summarizes the results of the 'Workshop on Polarization and Beam Energy Measurements at the ILC', held at DESY (Zeuthen) April 9-11 2008. The topics for the workshop included (1) physics requirements, (2) polarized sources and low energy polarimetry, (3) BDS polarimeters, (4) BDS energy spectrometers, and (5) physics-based measurements of beam polarization and beam energy from collider data. Discussions focused on the current ILC baseline program as described in the Reference Design Report (RDR), which includes physics runs at beam energies between 100 and 250 GeV, as well as calibration runs on the Z-pole. Electron polarization of P{sub e{sup -}} {approx}> 80% and positron polarization of P{sub e{sup +}} {approx}> 30% are part of the baseline configuration of the machine. Energy and polarization measurements for ILC options beyond the baseline, including Z-pole running and the 1 TeV energy upgrade, were also discussed.
Date: July 25, 2008
Creator: Aurand, B.; Bailey, I.; Bartels, C.; Blair, G.; Brachmann, A.; Clarke, J. et al.
Object Type: Article
System: The UNT Digital Library
The Use of Small Coolers in a Magnetic Field (open access)

The Use of Small Coolers in a Magnetic Field

Small 4 K coolers are used to cool superconducting magnets.These coolers are usually used with high temperature suerconductor (HTS)leads. In most cases, magnet is shielded with iron or active shieldcoils. Thus the field at the cooler is low. There are instances when thecooler must be in a magnetic field. Gifford McMahon (GM) coolers or pulsetube coolers are commercially available to cool the magnets. This paperwill discuss how the two types of coolers are affected by the straymagnetic field. Strategies for using coolers on magnets that generatestray magnetic fields are discussed.
Date: July 25, 2007
Creator: Green, Michael A. & Witte, Holger
Object Type: Article
System: The UNT Digital Library
Study of the Decay Ds+ to K+K-e+nu (open access)

Study of the Decay Ds+ to K+K-e+nu

Using 214 fb{sup -1} of data recorded by the BABAR detector at the PEPII electron-positron collider, they study the decay D{sub s}{sup +} {yields} K{sup +}K{sup -}e{sup +}{nu}{sub e}. Except for a small S-wave contribution, the events with K{sup +}K{sup -} masses in the range 1.01-1.03 GeV/c{sup 2} correspond to {phi} mesons. For D{sub s}{sup +} {yields} {phi}e{sup +}{nu}{sub e} decays, they measure the relative normalization of the Lorentz invariant form factors at q{sup 2} = 0, r{sub V} = V(0)/A{sub 1}(0) = 1.849 {+-} 0.060 {+-} 0.095, r{sub 2} = A{sub 2}(0)/A{sub 1}(0) = 0.763 {+-} 0.071 {+-} 0.065 and the pole mass of the axial-vector form factors m{sub A} = (2.28{sub -0.18}{sup +0.23} {+-} 0.18) GeV/c{sup 2}. Within the same K{sup +}K{sup -} mass range, they also measure the relative branching fractions {Beta}(D{sub s}{sup +} {yields} K{sup +}K{sup -}e{sup +}{nu}{sub e})/{Beta}(D{sub s}{sup +} {yields} K{sup +}K{sup -}{pi}{sup +}) - 0.558 {+-} 0.007 {+-} 0.016, from which they obtain the total branching fraction {Beta}(D{sub s}{sup +} {yields} {phi}e{sup +}{nu}{sub e}) = (2.61 {+-} 0.03 {+-} 0.08 {+-} 0.15) x 10{sup -2}. By comparing this value with the predicted decay rate, they extract A{sub 1}(0) = 0.607 {+-} 0.011 {+-} …
Date: July 25, 2008
Creator: Aubert, B.; Bona, M.; Karyotakis, Y.; Lees, J. P.; Poireau, V.; Prencipe, E. et al.
Object Type: Article
System: The UNT Digital Library
A Variation of the F-Test for Determining Statistical Relevance ofParticular Parameters in EXAFS Fits (open access)

A Variation of the F-Test for Determining Statistical Relevance ofParticular Parameters in EXAFS Fits

A general problem when fitting EXAFS data is determining whether particular parameters are statistically significant. The F-test is an excellent way of determining relevancy in EXAFS because it only relies on the ratio of the fit residual of two possible models, and therefore the data errors approximately cancel. Although this test is widely used in crystallography (there, it is often called a 'Hamilton test') and has been properly applied to EXAFS data in the past, it is very rarely applied in EXAFS analysis. We have implemented a variation of the F-test adapted for EXAFS data analysis in the RSXAP analysis package, and demonstrate its applicability with a few examples, including determining whether a particular scattering shell is warranted, and differentiating between two possible species or two possible structures in a given shell.
Date: July 25, 2006
Creator: Downward, L.; Booth, C.H.; Lukens, W.W. & Bridges, F.
Object Type: Article
System: The UNT Digital Library