Calibration of a High Resolution Soft X-ray Spectrometer (open access)

Calibration of a High Resolution Soft X-ray Spectrometer

A high resolution grating spectrometer (HRGS) with 2400 line/mm variable line spacing grating for the 10-50 {angstrom} wavelength range has been designed for laser-produced plasma experiments at the Lawrence Livermore National Laboratory (LLNL). The spectrometer has a large radius of curvature, R=44.3 m, is operated at a 2{sup o} grazing angle and can record high signal-to-noise spectra when used with a low-noise, cooled, charge-coupled device detector. The instrument can be operated with a 10-25 {micro}m wide slit to achieve the best spectral resolving power on laser plasma sources, approaching 2000, or in slitless mode with a small symmetrical emission source. Results will be presented for the spectral response of the spectrometer cross-calibrated at the LLNL Electron Beam Ion Trap facility using the broadband x-ray energy EBIT Calorimeter Spectrometer (ECS).
Date: January 26, 2010
Creator: Dunn, J; Beiersdorfer, P; Brown, G V & Magee, E W
Object Type: Article
System: The UNT Digital Library
LLNL Genomic Assessment: Viral and Bacterial Sequencing Needs for TMTI, Task 1.4.2 Report (open access)

LLNL Genomic Assessment: Viral and Bacterial Sequencing Needs for TMTI, Task 1.4.2 Report

Good progress has been made on both bacterial and viral sequencing by the TMTI centers. While access to appropriate samples is a limiting factor to throughput, excellent progress has been made with respect to getting agreements in place with key sources of relevant materials. Sharing of sequenced genomes funded by TMTI has been extremely limited to date. The April 2010 exercise should force a resolution to this, but additional managerial pressures may be needed to ensure that rapid sharing of TMTI-funded sequencing occurs, regardless of collaborator constraints concerning ultimate publication(s). Policies to permit TMTI-internal rapid sharing of sequenced genomes should be written into all TMTI agreements with collaborators now being negotiated. TMTI needs to establish a Web-based system for tracking samples destined for sequencing. This includes metadata on sample origins and contributor, information on sample shipment/receipt, prioritization by TMTI, assignment to one or more sequencing centers (including possible TMTI-sponsored sequencing at a contributor site), and status history of the sample sequencing effort. While this system could be a component of the AFRL system, it is not part of any current development effort. Policy and standardized procedures are needed to ensure appropriate verification of all TMTI samples prior to the investment …
Date: January 26, 2010
Creator: Slezak, T; Borucki, M; Lam, M; Lenhoff, R & Vitalis, E
Object Type: Report
System: The UNT Digital Library
Alternate Alpha Induced Reactions for NIF Radiochemistry (open access)

Alternate Alpha Induced Reactions for NIF Radiochemistry

Radiochemical analysis of NIF capsule residues has been identified as a potential diagnostic of NIF capsule performance. In particular, alpha-induced nuclear reactions that occur on tracer elements added to the NIF capsule have been shown through simulation to be a very sensitive diagnostic for mix. The short range of the alpha particles makes them representative of the hot spot where they are created through the fusion of deuterium and tritium. Reactions on elements doped into the innermost part of the capsule ablator would therefore be sensitive to material that had mixed into the hot spot. Radiochemical determinations of activated detector elements may perhaps be the only true measure of mix that occurs in a NIF capsule, particularly in cases when the capsule fails.
Date: February 26, 2010
Creator: Shaughnessy, D A; Moody, K J & Bernstein, L A
Object Type: Report
System: The UNT Digital Library
EXAMINATION OF SHIPPING PACKAGES 9975-01968, 9975-04353 AND 9975-06870 (open access)

EXAMINATION OF SHIPPING PACKAGES 9975-01968, 9975-04353 AND 9975-06870

Three 9975 shipping packages were examined to investigate the non-conforming condition of an axial air gap greater than 1 inch. This condition typically indicates the presence of excess moisture in the fiberboard overpack, and may be accompanied by degradation in the fiberboard properties. In the case of these three packages, no excess moisture was present, and the fiberboard was not visibly degraded. However, the lower fiberboard assembly from 9975-06870 was separated into two pieces. The lead shield from 9975-04353 was heavily corroded, while the shield from 9975-01968 had very little corrosion. In the case of 9975-06870, the shield was covered by a stainless steel sleeve, and the condition of the lead was not observed. No other conditions of concern were observed in these three packages.
Date: April 26, 2010
Creator: Daugherty, W.
Object Type: Report
System: The UNT Digital Library
TANK OPERATIONS CONTRACT CONSTRUCTION MANAGEMENT METHODOLOGY (open access)

TANK OPERATIONS CONTRACT CONSTRUCTION MANAGEMENT METHODOLOGY

None
Date: February 26, 2010
Creator: Lesko, K. F. & Berriochoa, M. V.
Object Type: Article
System: The UNT Digital Library
TANK OPERATIONS CONTRACT CONSTRUCTION MANAGEMENT METHODOLOGY UTILIZING THE AGENCY METHOD OF CONSTRUCTION MANAGEMENT (open access)

TANK OPERATIONS CONTRACT CONSTRUCTION MANAGEMENT METHODOLOGY UTILIZING THE AGENCY METHOD OF CONSTRUCTION MANAGEMENT

Washington River Protection Solutions, LLC (WRPS) has faced significant project management challenges in managing Davis-Bacon construction work that meets contractually required small business goals. The unique challenge is to provide contracting opportunities to multiple small business constructioin subcontractors while performing high hazard work in a safe and productive manner. Previous to the WRPS contract, construction work at the Hanford Tank Farms was contracted to large companies, while current Department of Energy (DOE) Contracts typically emphasize small business awards. As an integral part of Nuclear Project Management at Hanford Tank Farms, construction involves removal of old equipment and structures and installation of new infrastructure to support waste retrieval and waste feed delivery to the Waste Treatment Plant. Utilizing the optimum construction approach ensures that the contractors responsible for this work are successful in meeting safety, quality, cost and schedule objectives while working in a very hazardous environment. This paper descirbes the successful transition from a traditional project delivery method that utilized a large business general contractor and subcontractors to a new project construction management model that is more oriented to small businesses. Construction has selected the Agency Construction Management Method (John E Schaufelberger, Len Holm, "Management of Construction Projects, A Constructor's …
Date: February 26, 2010
Creator: Lesko, K. F. & Berriochoa, M. V.
Object Type: Article
System: The UNT Digital Library
Simple Model of the (alpha)(omega) Dynamo: Self-Excited Spheromaks (open access)

Simple Model of the (alpha)(omega) Dynamo: Self-Excited Spheromaks

The astrophysical {alpha}{omega} dynamo converting angular momentum to magnetic energy can be interpreted as a self-excited Faraday dynamo together with magnetic relaxation coupling the dynamo poloidal field to the toroidal field produced by dynamo currents. Since both toroidal and poloidal fields are involved, the system can be modeled as helicity creation and transport, in a spheromak plasma configuration in quasi-equilibrium on the time scale of changes in magnetic energy. Neutral beams or plasma gun injection across field lines could create self-excited spheromaks in the laboratory.
Date: January 26, 2010
Creator: Fowler, T K
Object Type: Report
System: The UNT Digital Library
Comprehensive Characterization of Voids and Microstructure in TATB-based Explosives from 10 nm to 1 cm: Effects of Temperature Cycling and Compressive Creep (open access)

Comprehensive Characterization of Voids and Microstructure in TATB-based Explosives from 10 nm to 1 cm: Effects of Temperature Cycling and Compressive Creep

This paper outlines the characterization of voids and Microstructure in TATB-based Explosives over several orders of magnitude, from sizes on the order of 10 nm to about 1 cm. This is accomplished using ultra small angle x-ray scattering to investigate voids from a few nm to a few microns, ultra small angle neutron scattering for voids from 100 nm to 10 microns, and x-ray computed microtomography to investigate microstructure from a few microns to a few centimeters. The void distributions of LX-17 are outlined, and the microstructure of LX-17 is presented. Temperature cycling and compressive creep cause drastically different damage to the microstructure. Temperature cycling leads to a volume expansion (ratchet growth) in TATB-based explosives, and x-ray scattering techniques that are sensitive to sizes up to a few microns indicated changes to the void volume distribution that had previously accounted for most, but not all of the change in density. This paper presents the microstructural damage larger than a few microns caused by ratchet growth. Temperature cycling leads to void creation in the binder poor regions associated with the interior portion of formulated prills. Conversely, compressive creep causes characteristically different changes to microstructure; fissures form at binder-rich prill boundaries prior …
Date: February 26, 2010
Creator: Willey, T. M.; Lauderbach, L.; Gagliardi, F.; Cunningham, B.; Lorenz, K. T.; Lee, J. I. et al.
Object Type: Article
System: The UNT Digital Library
Laser-induced Ramp Compression of Tantalum and Iron to Over 300 GPa: EOS and X-ray Diffraction (open access)

Laser-induced Ramp Compression of Tantalum and Iron to Over 300 GPa: EOS and X-ray Diffraction

None
Date: January 26, 2010
Creator: Eggert, J. H.; Bastea, M.; Braun, D.; Fujino, D.; Rygg, R.; Smith, R. et al.
Object Type: Article
System: The UNT Digital Library
Effects of Temperature and Contamination on Mpcms Electrodes in 241-Ay-101 and 241-an-107 Tank Waste Simulants (open access)

Effects of Temperature and Contamination on Mpcms Electrodes in 241-Ay-101 and 241-an-107 Tank Waste Simulants

This report documents the results of tests designed to characterize the relationship between temperature and the measured potential of electrodes installed on multi-probe corrosion monitoring systems in waste tanks. This report also documents the results of tests designed to demonstrate the impact of liquid in-leakage into electrode bodies as well as the contamination of primary reference electrodes by diffusion through the electrode tip.
Date: March 26, 2010
Creator: Dahl, M. M.; Philo, S. L.; Edgemon, G. L.; Bell, J. L. S. & Moore, C. G.
Object Type: Report
System: The UNT Digital Library
Simulation of Intense Beams and Targets for Heavy-Ion-Fusion Science (HEDLP / Inertial Fusion Energy) (open access)

Simulation of Intense Beams and Targets for Heavy-Ion-Fusion Science (HEDLP / Inertial Fusion Energy)

None
Date: August 26, 2010
Creator: Friedman, A.; Barnard, J. J.; Cohen, R. H.; Dorf, M.; Eder, D.; Grote, D. P. et al.
Object Type: Report
System: The UNT Digital Library
"Snowflake" divertor configuration in NSTX (open access)

"Snowflake" divertor configuration in NSTX

None
Date: May 26, 2010
Creator: Soukhanovskii, V. A.; Ahn, J. W.; Bell, R. E.; Gates, D. A.; Gerhardt, S.; Kaita, R. et al.
Object Type: Article
System: The UNT Digital Library
Reaction cross-section predictions for nucleon induced reactions (open access)

Reaction cross-section predictions for nucleon induced reactions

None
Date: July 26, 2010
Creator: Nobre, G P; Thompson, I J; Escher, J E & Dietrich, F S
Object Type: Article
System: The UNT Digital Library
Surrogate Approaches for Neutron Capture (open access)

Surrogate Approaches for Neutron Capture

None
Date: May 26, 2010
Creator: Escher, J E; Dietrich, F S & Scielzo, N D
Object Type: Article
System: The UNT Digital Library
Advanced Initiation Systems Manufacturing Level 2 Milestone Completion Summary (open access)

Advanced Initiation Systems Manufacturing Level 2 Milestone Completion Summary

None
Date: August 26, 2010
Creator: Chow, R & Schmidt, M A
Object Type: Report
System: The UNT Digital Library
Direct characterization of phase transformations and morphologies in moving reaction zones in Al/Ni nanolaminates using dynamic transmission electron microscopy (open access)

Direct characterization of phase transformations and morphologies in moving reaction zones in Al/Ni nanolaminates using dynamic transmission electron microscopy

None
Date: August 26, 2010
Creator: Kim, J. S.; LaGrange, T.; Reed, B. W.; Knepper, R.; Weihs, T. P.; Browning, N. D. et al.
Object Type: Article
System: The UNT Digital Library
Kinetics of Ejected Particles During Laser-Induced Breakdown in Fused Silica (open access)

Kinetics of Ejected Particles During Laser-Induced Breakdown in Fused Silica

None
Date: July 26, 2010
Creator: Raman, R N; Negres, R A & Demos, S G
Object Type: Article
System: The UNT Digital Library
Mechanical Damage, Ignition, and Burn: Experiment, Model Development, and Computer Simulations to Study High-Explosive Violent Response (HEVR) (open access)

Mechanical Damage, Ignition, and Burn: Experiment, Model Development, and Computer Simulations to Study High-Explosive Violent Response (HEVR)

None
Date: January 26, 2010
Creator: Reaugh, J E & Jones, A G
Object Type: Article
System: The UNT Digital Library
Verification with gamma-ray and fast neutron detection (open access)

Verification with gamma-ray and fast neutron detection

None
Date: May 26, 2010
Creator: Wurtz, R. E.; Glenn, A. M.; Kerr, P. L.; Kim, K. S.; Nakae, L. F.; Newby, R. J. et al.
Object Type: Article
System: The UNT Digital Library
Turbulence Considerations for Comparing Ecosystem Exchange over Old-Growth and Clear-Cut Stands with Limited Fetch and Complex Canopy Flows (open access)

Turbulence Considerations for Comparing Ecosystem Exchange over Old-Growth and Clear-Cut Stands with Limited Fetch and Complex Canopy Flows

None
Date: July 26, 2010
Creator: Wharton, S.; Paw U, K. T.; Schroeder, M.; Bible, K. & Falk, M.
Object Type: Article
System: The UNT Digital Library
Reaction Mechanisms for Barite Dissolution and Growth (open access)

Reaction Mechanisms for Barite Dissolution and Growth

In Stack and Rustad (2007), the reactive flux method (Rey and Hynes, 1996) and molecular dynamics (MD) were used to simulate the {001} barite-water interface structure and water exchange rate of aqueous barium ions and barium surface species. Atomic-level mineralwater interfacial structure and kinetics are being studied with increasing precision due to advances in spectroscopic methods at synchrotron x-ray sources as well as improved computational capacity. Better characterization of these interfaces in turn is leading to advances in the understanding of many macroscopic geochemical properties. Overall the barite-water interfacial structure was found to compare well to that estimated using X-ray reflectivity (XRR) measurements (Fenter et al., 2001), but there was an important difference: the MD predicted an intricate water structure present at the interface with one major peak and several minor peaks whereas the XRR found only a single layer of water. This discrepancy is thought to result from a limited resolution in the Fenter et al. (2001) study as well as over-coordination of surface sulfates by the MD model.
Date: July 26, 2010
Creator: Stack, Andrew G.
Object Type: Report
System: The UNT Digital Library
Results of applying a non-evaporative mitigation technique to laser-initiated surface damage on fused-silica (open access)

Results of applying a non-evaporative mitigation technique to laser-initiated surface damage on fused-silica

We present results from a study to determine an acceptable CO{sub 2} laser-based non-evaporative mitigation protocol for use on surface damage sites in fused-silica optics. A promising protocol is identified and evaluated on a set of surface damage sites created under ICF-type laser conditions. Mitigation protocol acceptability criteria for damage re-initiation and growth, downstream intensification, and residual stress are discussed. In previous work, we found that a power ramp at the end of the protocol effectively minimizes the residual stress (<25 MPa) left in the substrate. However, the biggest difficulty in determining an acceptable protocol was balancing between low re-initiation and problematic downstream intensification. Typical growing surface damage sites mitigated with a candidate CO{sub 2} laser-based mitigation protocol all survived 351 nm, 5 ns damage testing to fluences >12.5 J/cm{sup 2}. The downstream intensification arising from the mitigated sites is evaluated, and all but one of the sites has 100% passing downstream damage expectation values. We demonstrate, for the first time, a successful non-evaporative 10.6 {micro}m CO{sub 2} laser mitigation protocol applicable to fused-silica optics used on fusion-class lasers like the National Ignition Facility (NIF).
Date: October 26, 2010
Creator: Adams, J. J.; Bolourchi, M.; Bude, J. D.; Guss, G. M.; Matthews, M. J. & Nostrand, M. C.
Object Type: Article
System: The UNT Digital Library
Primer on Use of Multi-Spectral and Infra Red Imaging for On-Site Inspections (open access)

Primer on Use of Multi-Spectral and Infra Red Imaging for On-Site Inspections

The purpose of an On-Site Inspection (OSI) is to determine whether a nuclear explosion has occurred in violation of the Comprehensive Nuclear Test Ban Treaty (CTBT), and to gather information which might assist in identifying the violator (CTBT, Article IV, Paragraph 35) Multi-Spectral and Infra Red Imaging (MSIR) is allowed by the treaty to detect observables which might help reduce the search area and thus expedite an OSI and make it more effective. MSIR is permitted from airborne measurements, and at and below the surface to search for anomalies and artifacts (CTBT, Protocol, Part II, Paragraph 69b). The three broad types of anomalies and artifacts MSIR is expected to be capable of observing are surface disturbances (disturbed earth, plant stress or anomalous surface materials), human artifacts (man-made roads, buildings and features), and thermal anomalies. The purpose of this Primer is to provide technical information on MSIR relevant to its use for OSI. It is expected that this information may be used for general background information, to inform decisions about the selection and testing of MSIR equipment, to develop operational guidance for MSIR use during an OSI, and to support the development of a training program for OSI Inspectors. References are …
Date: October 26, 2010
Creator: Henderson, J. R.
Object Type: Report
System: The UNT Digital Library
Integrated Nucleosynthesis in Neutrino Driven Winds (open access)

Integrated Nucleosynthesis in Neutrino Driven Winds

Although they are but a small fraction of the mass ejected in core-collapse supernovae, neutrino-driven winds (NDWs) from nascent proto-neutron stars (PNSs) have the potential to contribute significantly to supernova nucleosynthesis. In previous works, the NDW has been implicated as a possible source of r-process and light p-process isotopes. In this paper we present time-dependent hydrodynamic calculations of nucleosynthesis in the NDW which include accurate weak interaction physics coupled to a full nuclear reaction network. Using two published models of PNS neutrino luminosities, we predict the contribution of the NDW to the integrated nucleosynthetic yield of the entire supernova. For the neutrino luminosity histories considered, no true r-process occurs in the most basic scenario. The wind driven from an older 1.4M{sub {circle_dot}} model for a PNS is moderately neutron-rich at late times however, and produces {sup 87}Rb, {sup 88}Sr, {sup 89}Y, and {sup 90}Zr in near solar proportions relative to oxygen. The wind from a more recently studied 1.27M{sub {circle_dot}} PNS is proton-rich throughout its entire evolution and does not contribute significantly to the abundance of any element. It thus seems very unlikely that the simplest model of the NDW can produce the r-process. At most, it contributes to the …
Date: March 26, 2010
Creator: Roberts, L F; Woosley, S E & Hoffman, R D
Object Type: Article
System: The UNT Digital Library