Laser System for Photoelectron and X-Ray Production in the PLEIADES Compton Light Source (open access)

Laser System for Photoelectron and X-Ray Production in the PLEIADES Compton Light Source

The PLEIADES (Picosecond Laser-Electron Interaction for the Dynamic Evaluation of Structures) facility provides tunable short x-ray pulses with energies of 30-140 keV and pulse durations of 0.3-5 ps by scattering an intense, ultrashort laser pulse off a 35-75 MeV electron beam. Synchronization of the laser and electron beam is obtained by using a photoinjector gun, and using the same laser system to generate the electrons and the scattering laser. The Ti Ti:Sapphire, chirped pulse amplification based 500 mJ, 50 fs, 810 nm scattering laser and the similar 300 {micro}J, 5 ps, 266 nm photoinjector laser systems are detailed. Additionally, an optical parametric chirped pulse amplification (OPCPA) system is studied as a replacement for part of the scattering laser front end. Such a change would significantly simplify the set-up the laser system by removing the need for active switching optics, as well as increase the pre-pulse contrast ratio which will be important when part of the scattering laser is used as a pump beam in pump-probe diffraction experiments using the ultrashort tunable x-rays generated as the probe.
Date: April 21, 2005
Creator: Gibson, D J; Barty, C J; Betts, S M; Crane, J K & Jovanovic, I
Object Type: Article
System: The UNT Digital Library
The Development of a Detailed Chemical Kinetic Mechanism for Diisobutylene and Comparison to Shock Tube Ignition Times (open access)

The Development of a Detailed Chemical Kinetic Mechanism for Diisobutylene and Comparison to Shock Tube Ignition Times

There is much demand for chemical kinetic models to represent practical fuels such as gasoline, diesel and aviation fuel. These blended fuels contain hundreds of components whose identity and amounts are often unknown. A chemical kinetic mechanism that would represent the oxidation of all these species with accompanying chemical reactions is intractable with current computational capabilities, chemical knowledge and manpower resources. The use of surrogate fuels is an approach to make the development of chemical kinetic mechanisms for practical fuels tractable. A surrogate fuel model consists of a small number of fuel components that can be used to represent the practical fuel and still predict desired characteristics of the practical fuel. These desired fuel characteristics may include ignition behavior, burning velocity, fuel viscosity, fuel vaporization, and fuel emissions (carbon monoxide, hydrocarbons, soot and nitric oxides). Gasoline consists of many different classes of hydrocarbons including n-alkanes, alkenes, iso-alkanes, cycloalkanes, cycloalkenes, and aromatics. One approach is to use a fuel surrogate that has a single component from each class of hydrocarbon in gasoline so that the unique molecular structure of each class is represented. This approach may lead to reliable predictions of many of the combustion properties of the practical fuel. In …
Date: January 21, 2005
Creator: Metcalfe, W; Curran, H J; Simmie, J M; Pitz, W J & Westbrook, C K
Object Type: Article
System: The UNT Digital Library
Appendix D-12A Building 332C Waste Accumulation Area (open access)

Appendix D-12A Building 332C Waste Accumulation Area

This appendix is designed to provide information specific to the Building 332C Waste Accumulation Area (B-332C WAA), a waste storage area. This appendix is not designed to be used as a sole source of information. All general information that is not specific to the B-332C WAA is included in the Contingency Plan for Waste Accumulation Areas, dated July 2004, and should be referenced. The B-332C WAA is located in the southwest quadrant of the LLNL Main Site in Building 332, Room 1330. Hazardous and mixed wastes may be stored at the B-332C WAA for 90 days or less, until transferred to the appropriate Radioactive and Hazardous Waste Management (RHWM) facility or other permitted treatment, storage or disposal facility (TSDF). Radioactive waste may also be stored at the WAA. The design storage capacity of this WAA is 2,200 gallons.
Date: January 21, 2005
Creator: Chase, Dawn
Object Type: Report
System: The UNT Digital Library
HIF VNL Progress Report to DOE, April 22, 2005 (open access)

HIF VNL Progress Report to DOE, April 22, 2005

We have made progress in learning to use the code Hydra to do detailed modeling of targets for Accelerator Driven High Energy Density Physics. Hydra is a state-of-the-art 3D, radiative transfer hydrodynamics modeling code developed at LLNL. In particular, we have carried out two-dimensional simulations of a 23 MeV, 1 mm radius Neon beam striking a 48 micron thick Aluminum foil at 10% solid density, and observed the heating of the foil by the beam. The Bragg peak was chosen to fall near the center of the foil, and as expected, rarefaction waves propagated symmetrically inward (at a speed of order the sound speed), as the heated material flowed outward and cooled. Foams allow relatively high temperatures to be attained over longer timescales, and the foils behaved, at least qualitatively, as predicted by previous analysis. Design of a number of configurations, ion species, and material compositions will be carried out using this code. Further, calculations by our collaborators at Tech-X corporation have compared results from the SRIM code (a code for understanding detailed energy deposition and scattering of ions in a cold solid) with cold dEdX curves published by Northcliffe and Schilling in 1970. The latter publication was used for …
Date: April 21, 2005
Creator: Barnard, J
Object Type: Report
System: The UNT Digital Library
On the Definition of the Number of Temporal Modes in the Sase Output. (open access)

On the Definition of the Number of Temporal Modes in the Sase Output.

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Date: August 21, 2005
Creator: Krinsky, S.
Object Type: Article
System: The UNT Digital Library
Cryogenic loading of large volume presses for high-pressure experimentation and synthesis of novel materials (open access)

Cryogenic loading of large volume presses for high-pressure experimentation and synthesis of novel materials

We present an efficient easily implemented method for loading cryogenic fluids in a large volume press. We specifically apply this method to the high-pressure synthesis of an extended solid derived from CO using a Paris-Edinburgh cell. This method employs cryogenic cooling of Bridgman type WC anvils well insulated from other press components, condensation of the load gas within a brass annulus surrounding the gasket between the Bridgman anvils. We demonstrate the viability of the described approach by synthesizing macroscopic amounts (several milligrams) of polymeric CO-derived material, which were recovered to ambient conditions after compression of pure CO to 5 GPa or above.
Date: January 21, 2005
Creator: Lipp, M. J.; Evans, W. J. & Yoo, C. S.
Object Type: Article
System: The UNT Digital Library
Uranium Geochemistry in Vadose Zone and Aquifer Sediments from the 300 Area Uranium Plume (open access)

Uranium Geochemistry in Vadose Zone and Aquifer Sediments from the 300 Area Uranium Plume

This report documents research conducted by the RCS Project to update the record of decision for the 300-FF-5 Operable Unit on the Hanford Site.
Date: July 21, 2005
Creator: Zachara, John M.; Davis, Jim A.; Liu, Chongxuan; McKinley, James P.; Qafoku, Nik; Wellman, Dawn M. et al.
Object Type: Report
System: The UNT Digital Library
A Dual-Mode Actinic EUV Mask Inspection Tool (open access)

A Dual-Mode Actinic EUV Mask Inspection Tool

To qualify the performance of non-actinic inspection tools, a novel EUV mask inspection system has been installed at the Advanced Light Source (ALS) synchrotron facility at Lawrence Berkeley National Laboratory. Similar to the older generation actinic mask inspection tool, the new system can operate in scanning mode, when mask blanks are scanned for defects using 13.5-nm in-band radiation to identify and map all locations on the mask that scatter a significant amount of EUV light. By modifying and optimizing beamline optics (11.3.2 at ALS) and replacing K-B focusing mirrors with a high quality Schwarzschild illuminator, the new system achieves an order of magnitude improvement on in-band EUV flux density at the mask, enabling faster scanning speed and higher sensitivity to smaller defects. Moreover, the system can also operate in imaging mode, when it becomes a zone-plate-based full-field EUV microscope with spatial resolution better than 100 nm. The microscope utilizes an off-axis setup, making it possible to obtain bright field images over a field-of-view of 5 x 5 {micro}m.
Date: March 21, 2005
Creator: Liu, Y.; Barty, A.; Gullikson, E.; S. Taylor, J.; Liddle, J. A. & Wood, O.
Object Type: Article
System: The UNT Digital Library
An Analysis of Microbial Pollution in the Sinclair-Dyes Inlet Watershed (open access)

An Analysis of Microbial Pollution in the Sinclair-Dyes Inlet Watershed

This assessment of fecal coliform sources and pathways in Sinclair and Dyes Inlets is part of the Project ENVironmental InVESTment (ENVVEST) being conducted by the Navy's Puget Sound Naval Shipyard and Intermediate Maintenance Facility in cooperation with the US Environmental Protection Agency, Washington State Department of Ecology, the Suquamish Tribe, Kitsap County, the City of Bremerton, the City of Port Orchard, and other local stakeholders. The goal of this study was to identify microbial pollution problems within the Sinclair-Dyes Inlet watershed and to provide a comprehensive assessment of fecal coliform (FC) contamination from all identifiable sources in the watershed. This study quantifies levels of contamination and estimated loadings from known sources within the watersheds and describes pollutant transport mechanisms found in the study area. In addition, the effectiveness of pollution prevention and mitigation measures currently in place within the Sinclair-Dyes Inlet watershed are discussed. This comprehensive study relies on historical data collected by several cooperating agencies, in addition to data collected during the study period from spring 2001 through summer 2005. This report is intended to provide the technical information needed to continue current water quality cleanup efforts and to help implement future efforts.
Date: September 21, 2005
Creator: May, Christopher W. & Cullinan, Valerie I.
Object Type: Report
System: The UNT Digital Library
Interim-Status RCRA Groundwater Monitoring Plan for the 216-A-10, 216-A-36B, and 216-A-37-1 PUREX Cribs (open access)

Interim-Status RCRA Groundwater Monitoring Plan for the 216-A-10, 216-A-36B, and 216-A-37-1 PUREX Cribs

This document presents a groundwater monitoring program for three Resource Conservation and Recovery Act of 1976 (RCRA) waste management units at the Hanford Site combined under one groundwater quality assessment program. The units are the 216 A 10, 216 A 36B, and 216 A-37-1 cribs (the RCRA PUREX cribs). The three cribs have been grouped together based on their proximity to one another, similar construction and waste history, and similar hydrogeologic regime. The RCRA PUREX cribs are located in the 200 East Area of the Hanford Site. This document replaces the previous RCRA monitoring plan (Lindberg 1997-PNNL-11523, Rev.0) for these cribs.
Date: July 21, 2005
Creator: Lindberg, Jon W. & Elmore, Rebecca P.
Object Type: Report
System: The UNT Digital Library
CHEMICAL REACTIVITY TEST: Assessing Thermal Stability and Chemical Compatibility (open access)

CHEMICAL REACTIVITY TEST: Assessing Thermal Stability and Chemical Compatibility

The thermal stability of high explosive (HE) and its compatibility with other materials are of critical importance in storage and handling practices. These properties are measured at Lawrence Livermore National Laboratory using the chemical reactivity test (CRT). The CRT measures the total amount of gas evolved from a material or combination of materials after being heat treated for a designated period of time. When the test result is compared to a threshold value, the relative thermal stability of an HE or the compatibility of an HE with other materials is determined. We describe the CRT testing apparatus, the experimental procedure, and the comparison methodology and provide examples and discussion of results.
Date: April 21, 2005
Creator: Koerner, J.; Tran, T.; Gagliardi, F. & Fontes, A.
Object Type: Article
System: The UNT Digital Library
Fluctuation Results Fro PHENIX. (open access)

Fluctuation Results Fro PHENIX.

The PHENIX Experiment at the Relativistic Heavy Ion Collider has made measurements of event-by-event fluctuations in the net charge, the mean transverse momentum, and the charged particle multiplicity as a function of collision energy, centrality, and transverse momentum in heavy ion collisions. The results of these measurements will be reviewed and discussed.
Date: April 21, 2005
Creator: Mitchell, J. T.
Object Type: Article
System: The UNT Digital Library
Bounds on Transport Coefficients of Porous Media (open access)

Bounds on Transport Coefficients of Porous Media

An analytical formulation of conductivity bounds by Bergman and Milton is used in a different way to obtain rigorous bounds on the real transport coefficients (electrical conductivity, thermal conductivity, and/or fluid permeability) of a fluid-saturated porous medium. These bounds do not depend explicitly on the porosity, but rather on two formation factors--one associated with the pore space and the other with the solid frame. Hashin-Shtrikman bounds for transport in random polycrystals of porous-material laminates will also be discussed.
Date: March 21, 2005
Creator: Berger, E. L.
Object Type: Article
System: The UNT Digital Library
Required Be Capsule Strength For Room Temperature Transport (open access)

Required Be Capsule Strength For Room Temperature Transport

The purpose of this memo is to lay out the criteria for the Be capsule strength necessary for room temperature transport. Ultimately we will test full thickness capsules by sealing high pressures inside, but currently we are limited to both thinner capsules and alternative measures of capsule material strength.
Date: March 21, 2005
Creator: Cook, B
Object Type: Report
System: The UNT Digital Library
Ultrasonic Examination of Double-Shell Tank 241-AP-102. February 2005 (open access)

Ultrasonic Examination of Double-Shell Tank 241-AP-102. February 2005

COGEMA Engineering Corporation (COGEMA), under a contract from CH2M Hill Hanford Group (CH2M Hill), has performed an ultrasonic nondestructive examination of selected portions of Double-Shell Tank 241-AP-102. The purpose of this examination was to provide information that could be used to evaluate the integrity of the wall of the primary tank. The requirements for the ultrasonic examination of Tank 241-AP-102 were to detect, characterize (identify, size, and locate), and record measurements made of any wall thinning, pitting, or cracks that might be present in the wall of the primary tank. Any measurements that exceed the requirements set forth in the Engineering Task Plan (ETP), RPP-22571 (Jensen 2004) and summarized on page 1 of this document, are reported to CH2M Hill and the Pacific Northwest National Laboratory (PNNL) for further evaluation. Under the contract with CH2M Hill, all data is to be recorded on disk and paper copies of all measurements are provided to PNNL for third-party evaluation. PNNL is responsible for preparing a report that describes the results of the COGEMA ultrasonic examinations.
Date: March 21, 2005
Creator: Pardini, Allan F. & Posakony, Gerald J.
Object Type: Report
System: The UNT Digital Library
High Average Power Optical FEL Amplifiers. (open access)

High Average Power Optical FEL Amplifiers.

Historically, the first demonstration of the optical FEL was in an amplifier configuration at Stanford University [l]. There were other notable instances of amplifying a seed laser, such as the LLNL PALADIN amplifier [2] and the BNL ATF High-Gain Harmonic Generation FEL [3]. However, for the most part FELs are operated as oscillators or self amplified spontaneous emission devices. Yet, in wavelength regimes where a conventional laser seed can be used, the FEL can be used as an amplifier. One promising application is for very high average power generation, for instance FEL's with average power of 100 kW or more. The high electron beam power, high brightness and high efficiency that can be achieved with photoinjectors and superconducting Energy Recovery Linacs (ERL) combine well with the high-gain FEL amplifier to produce unprecedented average power FELs. This combination has a number of advantages. In particular, we show that for a given FEL power, an FEL amplifier can introduce lower energy spread in the beam as compared to a traditional oscillator. This properly gives the ERL based FEL amplifier a great wall-plug to optical power efficiency advantage. The optics for an amplifier is simple and compact. In addition to the general features …
Date: August 21, 2005
Creator: Ben-Zvi, Ilan & Litvinenko, V.
Object Type: Article
System: The UNT Digital Library
Near-conservative behavior of 129Iodine in the Orange County Aquifer System, California (open access)

Near-conservative behavior of 129Iodine in the Orange County Aquifer System, California

Iodine is a biophilic element, with one stable isotope, {sup 127}I, and one long-lived radioisotope, {sup 129}I, which originates in the surface environment almost entirely from anthropogenic activities such as nuclear fuel reprocessing. Very few studies have evaluated the geochemical behavior of iodine isotopes in the subsurface. The concentrations of {sup 129}I and {sup 127}I were measured in wells fed by a series of artificial recharge ponds in the Forebay Area of the Orange County groundwater basin (California, USA) to evaluate their potential use as hydrological tracers. To substantiate interpretation of {sup 129}I and {sup 127}I concentration data, the aquifer system was evaluated using literature values of aquifer water mass age based on {sup 3}H/{sup 3}He, Xenon and {delta}{sup 18}O tracer data, as well as time-series data of Santa Ana River flow rates over the past decade. The aquifer data demonstrate the nearly conservative behavior of {sup 129}I, with {sup 129}I/{sup 127}I ratios likely reflecting variations in source functions as well as climatic conditions, and with inferred particle-water partition coefficients (K{sub d}) of 0.1 cm{sup 3} g{sup -1} or less.
Date: January 21, 2005
Creator: Schwer, K. A.; Santschi, P H; Moran, J. E. & Elmore, D.
Object Type: Article
System: The UNT Digital Library
Estimation of (n,f) Cross-Sections by Measuring Reaction Probability Ratios (open access)

Estimation of (n,f) Cross-Sections by Measuring Reaction Probability Ratios

Neutron-induced reaction cross-sections on unstable nuclei are inherently difficult to measure due to target activity and the low intensity of neutron beams. In an alternative approach, named the 'surrogate' technique, one measures the decay probability of the same compound nucleus produced using a stable beam on a stable target to estimate the neutron-induced reaction cross-section. As an extension of the surrogate method, in this paper they introduce a new technique of measuring the fission probabilities of two different compound nuclei as a ratio, which has the advantage of removing most of the systematic uncertainties. This method was benchmarked in this report by measuring the probability of deuteron-induced fission events in coincidence with protons, and forming the ratio P({sup 236}U(d,pf))/P({sup 238}U(d,pf)), which serves as a surrogate for the known cross-section ratio of {sup 236}U(n,f)/{sup 238}U(n,f). IN addition, the P({sup 238}U(d,d{prime}f))/P({sup 236}U(d,d{prime}f)) ratio as a surrogate for the {sup 237}U(n,f)/{sup 235}U(n,f) cross-section ratio was measured for the first time in an unprecedented range of excitation energies.
Date: April 21, 2005
Creator: Plettner, C.; Ai, H.; Beausang, C. W.; Bernstein, L. A.; Ahle, L.; Amro, H. et al.
Object Type: Article
System: The UNT Digital Library
EMSL 2006 Strategic Plan (open access)

EMSL 2006 Strategic Plan

The 2006 EMSL Strategic Plan describes the elements of EMSL’s 5-year strategy to provide outstanding value to its user community and to meet evolving goals of the DOE Office of Biological Research.
Date: December 21, 2005
Creator: Campbell, Allison A.
Object Type: Report
System: The UNT Digital Library
Bacillus atrophaeus Outer Spore Coat Assembly and Ultrastructure (open access)

Bacillus atrophaeus Outer Spore Coat Assembly and Ultrastructure

Our previous atomic force microscopy (AFM) studies successfully visualized native Bacillus atrophaeus spore coat ultrastructure and surface morphology. We have shown that the outer spore coat surface is formed by a crystalline array of {approx}11 nm thick rodlets, having a periodicity of {approx}8 nm. We present here further AFM ultrastructural investigations of air-dried and fully hydrated spore surface architecture. In the rodlet layer, planar and point defects, as well as domain boundaries, similar to those described for inorganic and macromolecular crystals, were identified. For several Bacillus species, rodlet structure assembly and architectural variation appear to be a consequence of species-specific nucleation and crystallization mechanisms that regulate the formation of the outer spore coat. We propose a unifying mechanism for nucleation and self-assembly of this crystalline layer on the outer spore coat surface.
Date: November 21, 2005
Creator: Plomp, M; Leighton, T J; Wheeler, K E; Pitesky, M E & Malkin, A J
Object Type: Article
System: The UNT Digital Library
Scaling, Microstructure and Dynamic Fracture (open access)

Scaling, Microstructure and Dynamic Fracture

The relationship between pullback velocity and impact velocity is studied for different microstructures in Cu. A size distribution of potential nucleation sites is derived under the conditions of an applied stochastic stress field. The size distribution depends on flow stress leading to a connection between the plastic flow appropriate to a given microstructure and nucleation rate. The pullback velocity in turn depends on the nucleation rate resulting in a prediction for the relationship between pullback velocity and flow stress. The theory is compared to observations of Cu on Cu gas-gun experiments (10-50 GPa) for a diverse set of microstructures. The scaling law is incorporated into a 1D finite difference code and is shown to reproduce the experimental data with one adjustable parameter that depends only on a nucleation exponent, {Lambda}.
Date: December 21, 2005
Creator: Minich, R W; Kumar, M; Schwarz, A & Cazamias, J
Object Type: Article
System: The UNT Digital Library
A Beamline for High Pressure Studies at the Advanced Light Source With a Superconducting Bending Magnet as the Source (open access)

A Beamline for High Pressure Studies at the Advanced Light Source With a Superconducting Bending Magnet as the Source

A new facility for high-pressure diffraction and spectroscopy using diamond anvil high-pressure cells has been built at the Advanced Light Source on Beamline 12.2.2. This beamline benefits from the hard X-radiation generated by a 6 Tesla superconducting bending magnet (superbend). Useful x-ray flux is available between 5 keV and 35 keV. The radiation is transferred from the superbend to the experimental enclosure by the brightness preserving optics of the beamline. These optics are comprised of: a plane parabola collimating mirror (M1), followed by a Kohzu monochromator vessel with a Si(111) crystals (E/{Delta}E {approx} 7000) and a W/B{sub 4}C multilayer (E/{Delta}E {approx} 100), and then a toroidal focusing mirror (M2) with variable focusing distance. The experimental enclosure contains an automated beam positioning system, a set of slits, ion chambers, the sample positioning goniometry and area detectors (CCD or image-plate detector). Future developments aim at the installation of a second end station dedicated for in situ laser-heating on one hand and a dedicated high-pressure single-crystal station, applying both monochromatic as well as polychromatic techniques.
Date: April 21, 2005
Creator: Kunz, M.; MacDowell, A. A.; Caldwell, W. A.; Cambie, D.; Celestre, R. S.; Domning, E. E. et al.
Object Type: Article
System: The UNT Digital Library
Dark Matter before the LHC in a Natural Supersymmetric StandardModel (open access)

Dark Matter before the LHC in a Natural Supersymmetric StandardModel

We show that the solid lower bound of about 10{sup -44} cm{sup 2} is obtained for the cross section between the supersymmetric dark matter and nucleon in a theory in which the supersymmetric fine-tuning problem is solved without extending the Higgs sector at the weak scale. This bound arises because of relatively small superparticle masses and a fortunate correlation that the two dominant diagrams for the dark matter detection always interfere constructively if the constraint from the b {yields} s{gamma} measurements is obeyed. It is, therefore, quite promising in the present scenario that the supersymmetric dark matter is discovered before the LHC, assuming that the dark matter is the lightest supersymmetric particle.
Date: September 21, 2005
Creator: Ryuichiro, Kitano & Yasunori, Nomura
Object Type: Article
System: The UNT Digital Library
Effective Error Bounds in Euler-Maclaurin-Based QuadratureSchemes (open access)

Effective Error Bounds in Euler-Maclaurin-Based QuadratureSchemes

We analyze the behavior of Euler-Maclaurin-basedintegrationschemes with the intention of deriving accurate andeconomicestimations of the error term.
Date: June 21, 2005
Creator: Bailey, David H. & Borwein, Jonathan M.
Object Type: Report
System: The UNT Digital Library