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Definition of Technology Readiness Levels for Transmutation Fuel Development

Description: To quantitatively assess the maturity of a given technology, the Technology Readiness Level (TRL) process is used. The TRL process has been developed and successfully used by the Department of Defense (DOD) for development and deployment of new technology and systems for defense applications. In addition, NASA has also successfully used the TRL process to develop and deploy new systems for space applications. Transmutation fuel development is a critical technology needed for closing the nuclear fuel cycle. Because the deployment of a new nuclear fuel forms requires a lengthy and expensive research, development, and demonstration program, applying the TRL concept to the transmutation fuel development program is very useful as a management and tracking tool. This report provides definition of the technology readiness level assessment process as defined for use in assessing nuclear fuel technology development for the Transuranic Fuel Development Campaign.
Date: January 1, 2008
Creator: (062056), Jon Carmack & (103171), Kemal O. Pasamehmetoglu
Item Type: Report

Review of Transmutation Fuel Studies

Description: The technology demonstration element of the Global Nuclear Energy Partnership (GNEP) program is aimed at demonstrating the closure of the fuel cycle by destroying the transuranic (TRU) elements separated from spent nuclear fuel (SNF). Multiple recycle through fast reactors is used for burning the TRU initially separated from light-water reactor (LWR) spent nuclear fuel. For the initial technology demonstration, the preferred option to demonstrate the closed fuel cycle destruction of TRU materials is a sodium-cooled fast reactor (FR) used as burner reactor. The sodium-cooled fast reactor represents the most mature sodium reactor technology available today. This report provides a review of the current state of development of fuel systems relevant to the sodium-cooled fast reactor. This report also provides a review of research and development of TRU-metal alloy and TRU-oxide composition fuels. Experiments providing data supporting the understanding of minor actinide (MA)-bearing fuel systems are summarized and referenced.
Date: January 1, 2008
Creator: (062056), Jon Carmack & (103171), Kemal O. Pasamehmetoglu
Item Type: Report

Assessment of Startup Fuel Options for the GNEP Advanced Burner Reactor (ABR)

Description: The Global Nuclear Energy Program (GNEP) includes a program element for the development and construction of an advanced sodium cooled fast reactor to demonstrate the burning (transmutation) of significant quantities of minor actinides obtained from a separations process and fabricated into a transuranic bearing fuel assembly. To demonstrate and qualify transuranic (TRU) fuel in a fast reactor, an Advanced Burner Reactor (ABR) prototype is needed. The ABR would necessarily be started up using conventional metal alloy or oxide (U or U, Pu) fuel. Startup fuel is needed for the ABR for the first 2 to 4 core loads of fuel in the ABR. Following start up, a series of advanced TRU bearing fuel assemblies will be irradiated in qualification lead test assemblies in the ABR. There are multiple options for this startup fuel. This report provides a description of the possible startup fuel options as well as possible fabrication alternatives available to the program in the current domestic and international facilities and infrastructure.
Date: February 1, 2008
Creator: (062056), Jon Carmack; (103171), Kemal O. Pasamehmetoglu & Alberstein, David
Item Type: Report

SELECTIVE CATALYTIC REDUCTION OF DIESEL ENGINE NOX EMISSIONS USING ETHANOL AS A REDUCTANT

Description: NOx emissions from a heavy-duty diesel engine were reduced by more than 90% and 80% utilizing a full-scale ethanol-SCR system for space velocities of 21000/h and 57000/h respectively. These results were achieved for catalyst temperatures between 360 and 400 C and for C1:NOx ratios of 4-6. The SCR process appears to rapidly convert ethanol to acetaldehyde, which subsequently slipped past the catalyst at appreciable levels at a space velocity of 57000/h. Ammonia and N2O were produced during conversion; the concentrations of each were higher for the low space velocity condition. However, the concentration of N2O did not exceed 10 ppm. In contrast to other catalyst technologies, NOx reduction appeared to be enhanced by initial catalyst aging, with the presumed mechanism being sulfate accumulation within the catalyst. A concept for utilizing ethanol (distilled from an E-diesel fuel) as the SCR reductant was demonstrated.
Date: August 24, 2003
Creator: (1)Kass, M; Thomas, J; Lewis, S; Storey, J; Domingo, N & Graves, R (2) Panov, A
Item Type: Article

RELATIONSHIP BETWEEN COMPOSITION AND TOXICITY OF ENGINE EMISSION SAMPLES

Description: Differences in the lung toxicity and bacterial mutagenicity of seven samples from gasoline and diesel vehicle emissions were reported previously [1]. Filter and vapor-phase semivolatile organic samples were collected from normal and high-emitter gasoline and diesel vehicles operated on chassis dynamometers on the Unified Driving Cycle, and the compositions of the samples were measured in detail. The two fractions of each sample were combined in their original mass collection ratios, and the toxicity of the seven samples was compared by measuring inflammation and tissue damage in rat lungs and mutagenicity in bacteria. There was good agreement among the toxicity response variables in ranking the samples and demonstrating a five-fold range of toxicity. The relationship between chemical composition and toxicity was analyzed by a combination of principal component analysis (PCA) and partial least squares regression (PLS, also known as projection to latent surfaces). The PCA /PLS analysis revealed the chemical constituents co-varying most strongly with toxicity and produced models predicting the relative toxicity of the samples with good accuracy. The results demonstrated the utility of the PCA/PLS approach, which is now being applied to additional samples, and it also provided a starting point for confirming the compounds that actually cause the effects.
Date: August 24, 2003
Creator: (1)Mauderly, J; Seagrave, J; McDonald & J (2)Eide,I (3)Zielinska, B (4)Lawson, D
Item Type: Article

Building America Residential System Research Results: Achieving 30% Whole House Energy Savings Level in Marine Climates; January 2006 - December 2006

Description: The Building America program conducts the system research required to reduce risks associated with the design and construction of homes that use an average of 30% to 90% less total energy for all residential energy uses than the Building America Research Benchmark, including research on homes that will use zero net energy on annual basis. To measure the program's progress, annual research milestones have been established for five major climate regions in the United States. The system research activities required to reach each milestone take from 3 to 5 years to complete and include research in individual test houses, studies in pre-production prototypes, and research studies with lead builders that provide early examples that the specified energy savings level can be successfully achieved on a production basis. This report summarizes research results for the 30% energy savings level and demonstrates that lead builders can successfully provide 30% homes in the Marine Climate Region on a cost neutral basis.
Date: December 1, 2006
Creator: (BAIHP), Building America Industrialized Housing Partnership; (BIRA), Building Industry Research Alliance; (BSC), Building Science Consortium; (CARB), Consortium for Advanced Residential Buildings; (DEG), Davis Energy Group; IBACOS et al.
Item Type: Report

Building America Residential System Research Results: Achieving 30% Whole House Energy Savings Level in Mixed-Humid Climates; January 2006 - December 2006

Description: The Building America program conducts the system research required to reduce risks associated with the design and construction of homes that use an average of 30% to 90% less total energy for all residential energy uses than the Building America Research Benchmark, including research on homes that will use zero net energy on annual basis. To measure the program's progress, annual research milestones have been established for five major climate regions in the United States. The system research activities required to reach each milestone take from 3 to 5 years to complete and include research in individual test houses, studies in pre-production prototypes, and research studies with lead builders that provide early examples that the specified energy savings level can be successfully achieved on a production basis. This report summarizes research results for the 30% energy savings level and demonstrates that lead builders can successfully provide 30% homes in the Mixed-Humid Climate Region on a cost-neutral basis.
Date: December 1, 2006
Creator: (BAIHP), Building America Industrialized Housing Partnership; (BIRA), Building Industry Research Alliance; (BSC), Building Science Consortium; (CARB), Consortium for Advanced Residential Buildings; (DEG), Davis Energy Group; IBACOS et al.
Item Type: Report

Building America Residential System Research Results: Achieving 30% Whole House Energy Savings Level in the Hot-Dry and Mixed-Dry Climates

Description: The Building America program conducts the system research required to reduce risks associated with the design and construction of homes that use an average of 30% to 90% less total energy for all residential energy uses than the Building America Research Benchmark, including research on homes that will use zero net energy on annual basis. To measure the program's progress, annual research milestones have been established for five major climate regions in the United States. The system research activities required to reach each milestone take from 3 to 5 years to complete and include research in individual test houses, studies in pre-production prototypes, and research studies with lead builders that provide early examples that the specified energy savings level can be successfully achieved on a production basis. This report summarizes research results for the 30% energy savings level and demonstrates that lead builders can successfully provide 30% homes in the Hot-Dry/Mixed-Dry Climate Region on a cost neutral basis.
Date: January 1, 2006
Creator: (BIRA), Building Industry Research Alliance; (BSC), Building Science Consortium; (CARB), Consortium for Advanced Residential Buildings; (DEG), Davis Energy Group; (FSEC), Florida Solar Energy Center; IBACOS et al.
Item Type: Report

Building America Residential System Research Results: Achieving 30% Whole House Energy Savings Level in Cold Climates

Description: The Building America program conducts the system research required to reduce risks associated with the design and construction of homes that use an average of 30% to 90% less total energy for all residential energy uses than the Building America Research Benchmark, including research on homes that will use zero net energy on annual basis. To measure the program's progress, annual research milestones have been established for five major climate regions in the United States. The system research activities required to reach each milestone take from 3 to 5 years to complete and include research in individual test houses, studies in pre-production prototypes, and research studies with lead builders that provide early examples that the specified energy savings level can be successfully achieved on a production basis. This report summarizes research results for the 30% energy savings level and demonstrates that lead builders can successfully provide 30% homes in Cold Climates on a cost-neutral basis.
Date: August 1, 2006
Creator: (BIRA), Building Industry Research Alliance; (BSC), Building Science Consortium; (CARB), Consortium for Advanced Residential Buildings; (FSEC), Florida Solar Energy Center; IBACOS & (NREL), National Renewable Energy Laboratory
Item Type: Report

Strategies for the Commercialization and Deployment of Greenhouse Gas Intensity-Reducing Technologies and Practices

Description: New technologies will be a critical component--perhaps the critical component--of our efforts to tackle the related challenges of energy security, climate change, and air pollution, all the while maintaining a strong economy. But just developing new technologies is not enough. Our ability to accelerate the market penetration of clean energy, enabling, and other climate-related technologies will have a determining impact on our ability to slow, stop, and reverse the growth in greenhouse gas (GHG) emissions. Title XVI, Subtitle A, of the Energy Policy Act of 2005 (EPAct 2005) directs the Administration to report on its strategy to promote the commercialization and deployment (C&D) of GHG intensity-reducing technologies and practices. The Act also requests the Administration to prepare an inventory of climate-friendly technologies suitable for deployment and to identify the barriers and commercial risks facing advanced technologies. Because these issues are related, they are integrated here within a single report that we, representing the Committee on Climate Change Science and Technology Integration (CCCSTI), are pleased to provide the President, the Congress, and the public. Over the past eight years, the Administration of President George W. Bush has pursued a series of policies and measures aimed at encouraging the development and deployment of advanced technologies to reduce GHG emissions. This report highlights these policies and measures, discusses the barriers to each, and integrates them within a larger body of other extant policy. Taken together, more than 300 policies and measures described in this document may be viewed in conjunction with the U.S. Climate Change Technology Program's (CCTP's) Strategic Plan, published in September 2006, which focuses primarily on the role of advanced technology and associated research and development (R&D) for mitigating GHG emissions. The CCTP, a multi-agency technology planning and coordination program, initiated by President Bush, and subsequently authorized in EPAct2005, is responsible ...
Date: January 1, 2009
Creator: (CCCSTI), Committee on Climate Change Science and Technology Integration
Item Type: Report

2006 Toxic Chemical Release Inventory Report for the Emergency Planning and Community Right-to-Know Act of 1986, Title III, Section 313

Description: For reporting year 2006, Los Alamos National Laboratory (LANL or the Laboratory) submitted Form R reports for lead as required under the Emergency Planning and Community Right-to-Know Act (EPCRA) Section 313. No other EPCRA Section 313 chemicals were used in 2006 above the reportable thresholds. This document was prepared to provide a description of the evaluation of EPCRA Section 313 chemical use and threshold determinations for LANL for calendar year 2006, as well as to provide background information about data included on the Form R reports. Section 313 of EPCRA specifically requires facilities to submit a Toxic Chemical Release Inventory Report (Form R) to the U.S. Environmental Protection Agency (EPA) and state agencies if the owners and operators manufacture, process, or otherwise use any of the listed toxic chemicals above listed threshold quantities. EPA compiles this data in the Toxic Release Inventory database. Form R reports for each chemical over threshold quantities must be submitted on or before July 1 each year and must cover activities that occurred at the facility during the previous year. In 1999, EPA promulgated a final rule on persistent bioaccumulative toxics (PBTs). This rule added several chemicals to the EPCRA Section 313 list of toxic chemicals and established lower reporting thresholds for these and other PBT chemicals that were already reportable. These lower thresholds became applicable in reporting year 2000. In 2001, EPA expanded the PBT rule to include a lower reporting threshold for lead and lead compounds. Facilities that manufacture, process, or otherwise use more than 100 lb of lead or lead compounds must submit a Form R.
Date: December 12, 2007
Creator: (ENV-EAQ), Ecology and Air Quality Group
Item Type: Report

Performance assessment analyses unique to Department of Energy spent nuclear fuel

Description: This paper describes the iterative process of grouping and performance assessment that has led to the current grouping of the U.S. Department of Energy (DOE) spent nuclear fuel (SNF). The unique sensitivity analyses that form the basis for incorporating DOE fuel into the total system performance assessment (TSPA) base case model are described. In addition, the chemistry that results from dissolution of DOE fuel and high level waste (HLW) glass in a failed co-disposal package, and the effects of disposal of selected DOE SNF in high integrity cans are presented.
Date: June 4, 2000
Creator: (INEEL), H. H. Loo & (DE&S), J. O. Duguid
Item Type: Article

Gamma-Ray Spectrometric Characterization of Overpacked CC104/107 RH-TRU Wastes: Surrogate Tests

Description: Development of the gamma-ray spectrometric technique termed GSAK (Gamma-Ray Spectrometry with Acceptable Knowledge) for the characterization of CC104/107 remote-handled transuranic (RH-TRU) wastes continued this year. Proof-of-principle measurements have been completed on the surrogate RH-TRU waste drums configured earlier this year. The GSAK technique uses conventional gamma-ray spectrometry to quantify the detectable fission product content of overpacked RH-TRU drums. These results are then coupled with the inventory report to characterize the waste drum content. The inventory report is based on process knowledge of the waste drum loading and calculations of the isotopic distribution in the spent fuel examined to generate the drummed wastes. Three RH-TRU surrogate drums were configured with encapsulated EBR-II driver fuel rod segments arranged in the surrogate drum assemblies. Segment-specific inventory calculations initially specified the radionuclide content of the fuel segments and thus the surrogate drums. Radiochemical assays performed on representative fuel element segments identified a problem in the accuracy of some of the fission and activation product inventory values and provided a basis for adjustment of the specified surrogate drum inventories. The three waste drum surrogates, contained within their 8.9 cm (3.5 inch) thick steel overpacks, were analyzed by gamma-ray spectrometry at the TREAT facility at Argonne National Laboratory-West. Seven fission and activation product radionuclides ({sup 54}Mn, {sup 60}Co, {sup 125}Sb, {sup 134}Cs, {sup 137}Cs, {sup 144}CePr, and {sup 154}Eu) were reliably detected. The gamma-ray spectral accuracy was very good. In all cases, a two-sigma error bar constructed about the measured value included the actual drum activity.
Date: May 1, 2000
Creator: (INEEL), J. K. Hartwell; (ANL), R. T. Klann & (INEEL), M. E. McIlwain
Item Type: Report

Waste Management Planned for the Advanced Fuel Cycle Facility

Description: The U.S. Department of Energy (DOE) Global Nuclear Energy Partnership (GNEP) program has been proposed to develop and employ advanced technologies to increase the proliferation resistance of spent nuclear fuels, recover and reuse nuclear fuel resources, and reduce the amount of wastes requiring permanent geological disposal. In the initial GNEP fuel cycle concept, spent nuclear fuel is to be reprocessed to separate re-useable transuranic elements and uranium from waste fission products, for fabricating new fuel for fast reactors. The separated wastes would be converted to robust waste forms for disposal. The Advanced Fuel Cycle Facility (AFCF) is proposed by DOE for developing and demonstrating spent nuclear fuel recycling technologies and systems. The AFCF will include capabilities for receiving and reprocessing spent fuel and fabricating new nuclear fuel from the reprocessed spent fuel. Reprocessing and fuel fabrication activities will generate a variety of radioactive and mixed waste streams. Some of these waste streams are unique and unprecedented. The GNEP vision challenges traditional U.S. radioactive waste policies and regulations. Product and waste streams have been identified during conceptual design. Waste treatment technologies have been proposed based on the characteristics of the waste streams and the expected requirements for the final waste forms. Results of AFCF operations will advance new technologies that will contribute to safe and economical commercial spent fuel reprocessing facilities needed to meet the GNEP vision. As conceptual design work and research and design continues, the waste management strategies for the AFCF are expected to also evolve.
Date: September 1, 2007
Creator: (INL), Soelberg
Item Type: Article

Risk Management on the National Compact Stellarator Project (NCSX)

Description: In its simplest form, risk management is a continuous assessment from project start to completion that identifies what can impact your project (i.e., what the risks are)., which of these risks are important, and identification and implementation of strategies to deal with these risks (both threats and opportunities). The National Compact Stellerator Experiment (NCSX) Project was a "first-of-a-kind" fusion experiment that was technically very challenging, primarily resulting from the complex component geometries and tight tolerances. Initial risk quantification approaches proved inadequate and contributed to the escalation of costs as the design evolved and construction started. After the Project was well into construction, a new risk management plan was adopted. This plan was based on successful Department of Energy (DOE) and industrial risk management precepts. This paper will address the importance of effective risk management processes and lessons learned. It is of note that a steady reduction of risk was observed in the last six months of the project.
Date: February 6, 2009
Creator: (NCSX), Risk Management on the National Compact Stellarator Project
Item Type: Report

COMPARISON OF CONSEQUENCE ANALYSIS RESULTS FROM TWO METHODS OF PROCESSING SITE METEOROLOGICAL DATA

Description: Consequence analysis to support documented safety analysis requires the use of one or more years of representative meteorological data for atmospheric transport and dispersion calculations. At minimum, the needed meteorological data for most atmospheric transport and dispersion models consist of hourly samples of wind speed and atmospheric stability class. Atmospheric stability is inferred from measured and/or observed meteorological data. Several methods exist to convert measured and observed meteorological data into atmospheric stability class data. In this paper, one year of meteorological data from a western Department of Energy (DOE) site is processed to determine atmospheric stability class using two methods. The method that is prescribed by the U.S. Nuclear Regulatory Commission (NRC) for supporting licensing of nuclear power plants makes use of measurements of vertical temperature difference to determine atmospheric stability. Another method that is preferred by the U.S. Environmental Protection Agency (EPA) relies upon measurements of incoming solar radiation, vertical temperature gradient, and wind speed. Consequences are calculated and compared using the two sets of processed meteorological data from these two methods as input data into the MELCOR Accident Consequence Code System 2 (MACCS2) code.
Date: April 25, 2007
Creator: (NOEMAIL), D
Item Type: Article

THERMAL EVALUATION OF CONTAMINATED LIQUID ONTO CELL FLOORS

Description: For the Salt Disposition Integration Project (SDIP), postulated events in the new Salt Waste Processing Facility (SWPF) can result in spilling liquids that contain Cs-137 and organics onto cell floors. The parameters of concern are the maximum temperature of the fluid following a spill and the time required for the maximum fluid temperature to be reached. Control volume models of the various process cells have been developed using standard conduction and natural convection relationships. The calculations are performed using the Mathcad modeling software. The results are being used in Consolidated Hazards Analysis Planning (CHAP) to determine the controls that may be needed to mitigate the potential impact of liquids containing Cs-137 and flammable organics that spill onto cell floors. Model development techniques and the ease of making model changes within the Mathcad environment are discussed. The results indicate that certain fluid spills result in overheating of the fluid, but the times to reach steady-state are several hundred hours. The long times allow time for spill clean up without the use of expensive mitigation controls.
Date: May 4, 2009
Creator: (NOEMAIL), J
Item Type: Article

SIMPLE TRANSIENT CALCULATIONS OF CELL FLAMMABLE GAS CONCENTRATIONS

Description: The Saltstone Facility at Savannah River Site (SRS) mixes low-level radiological liquid waste with grout for permanent disposal as cement in vault cells. The grout mixture is poured into each cell in approximately 17 batches (8 to 10 hours duration). The grout mixture contains ten flammable gases of concern that are released from the mixture into the cell. Prior to operations, simple parametric transient calculations were performed to develop batch parameters (including schedule of batch pours) to support operational efficiency while ensuring that a flammable gas mixture does not develop in the cell vapor space. The analysis demonstrated that a nonflammable vapor space environment can be achieved, with workable operational constraints, without crediting the ventilation flow as a safety system control. Isopar L was identified as the primary flammable gas of concern. The transient calculations balanced inflows of the flammable gases into the vapor space with credited outflows of diurnal breathing through vent holes and displacement from new grout pours and gases generated. Other important features of the analyses included identifying conditions that inhibited a well-mixed vapor space, the expected frequency and duration of such conditions, and the estimated level of stratification that could develop.
Date: May 6, 2009
Creator: (NOEMAIL), J; David Allison (NOEMAIL), D & John Mccord, J
Item Type: Article

PERSPECTIVES ON A DOE CONSEQUENCE INPUTS FOR ACCIDENT ANALYSIS APPLICATIONS

Description: Department of Energy (DOE) accident analysis for establishing the required control sets for nuclear facility safety applies a series of simplifying, reasonably conservative assumptions regarding inputs and methodologies for quantifying dose consequences. Most of the analytical practices are conservative, have a technical basis, and are based on regulatory precedent. However, others are judgmental and based on older understanding of phenomenology. The latter type of practices can be found in modeling hypothetical releases into the atmosphere and the subsequent exposure. Often the judgments applied are not based on current technical understanding but on work that has been superseded. The objective of this paper is to review the technical basis for the major inputs and assumptions in the quantification of consequence estimates supporting DOE accident analysis, and to identify those that could be reassessed in light of current understanding of atmospheric dispersion and radiological exposure. Inputs and assumptions of interest include: Meteorological data basis; Breathing rate; and Inhalation dose conversion factor. A simple dose calculation is provided to show the relative difference achieved by improving the technical bases.
Date: July 30, 2008
Creator: (NOEMAIL), K; Jonathan Lowrie, J; David Thoman (NOEMAIL), D & Austin Keller (NOEMAIL), A
Item Type: Article

SRS BEDROCK PROBABILISTIC SEISMIC HAZARD ANALYSIS (PSHA) DESIGN BASIS JUSTIFICATION (U)

Description: This represents an assessment of the available Savannah River Site (SRS) hard-rock probabilistic seismic hazard assessments (PSHAs), including PSHAs recently completed, for incorporation in the SRS seismic hazard update. The prior assessment of the SRS seismic design basis (WSRC, 1997) incorporated the results from two PSHAs that were published in 1988 and 1993. Because of the vintage of these studies, an assessment is necessary to establish the value of these PSHAs considering more recently collected data affecting seismic hazards and the availability of more recent PSHAs. This task is consistent with the Department of Energy (DOE) order, DOE O 420.1B and DOE guidance document DOE G 420.1-2. Following DOE guidance, the National Map Hazard was reviewed and incorporated in this assessment. In addition to the National Map hazard, alternative ground motion attenuation models (GMAMs) are used with the National Map source model to produce alternate hazard assessments for the SRS. These hazard assessments are the basis for the updated hard-rock hazard recommendation made in this report. The development and comparison of hazard based on the National Map models and PSHAs completed using alternate GMAMs provides increased confidence in this hazard recommendation. The alternate GMAMs are the EPRI (2004), USGS (2002) and a regional specific model (Silva et al., 2004). Weights of 0.6, 0.3 and 0.1 are recommended for EPRI (2004), USGS (2002) and Silva et al. (2004) respectively. This weighting gives cluster weights of .39, .29, .15, .17 for the 1-corner, 2-corner, hybrid, and Greens-function models, respectively. This assessment is judged to be conservative as compared to WSRC (1997) and incorporates the range of prevailing expert opinion pertinent to the development of seismic hazard at the SRS. The corresponding SRS hard-rock uniform hazard spectra are greater than the design spectra developed in WSRC (1997) that were based on the LLNL ...
Date: December 14, 2005
Creator: (NOEMAIL), R
Item Type: Report

Time-Resolved Hard X-Ray Spectrometer

Description: Wired array studies are being conducted at the SNL Z accelerator to maximize the x-ray generation for inertial confinement fusion targets and high energy density physics experiments. An integral component of these studies is the characterization of the time-resolved spectral content of the x-rays. Due to potential spatial anisotropy in the emitted radiation, it is also critical to diagnose the time-evolved spectral content in a space-resolved manner. To accomplish these two measurement goals, we developed an x-ray spectrometer using a set of high-speed detectors (silicon PIN diodes) with a collimated field-of-view that converged on a 1-cm-diameter spot at the pinch axis. Spectral discrimination is achieved by placing high Z absorbers in front of these detectors. We built two spectrometers to permit simultaneous different angular views of the emitted radiation. Spectral data have been acquired from recent Z shots for the radial and polar views. UNSPEC1 has been adapted to analyze and unfold the measured data to reconstruct the x-ray spectrum. The unfold operator code, UFO2, is being adapted for a more comprehensive spectral unfolding treatment.
Date: March 1, 2007
Creator: (NSTec), Kenneth Moya; (NSTec), Ian McKennaa; (NSTec), Thomas Keenana & (Sandia), Michael Cuneob
Item Type: Article

Large-Format X-Ray Pinhole Camera

Description: National Security Technologies, LLC, has successfully implemented many scientific and engineering innovations in the new Large-Format Pinhole Camera (LFPHC), which have dramatically increased the detection sensitivity and reliability of the camera in exotic locations, such as the Sandia National Laboratories Z-facility. Quality improvements of the LFPHC have been demonstrated in its fielding at Z, where high-quality images were recorded. A major improvement was the development of a new, user-friendly LFPHC camera back that would tolerate high radiation, electromagnetic interference, and mechanical shock. Key modifications resulted in improved detection sensitivity, spatial resolution, uniformity along the microchannel plate strip, and stability of the interframe timing and delay. Design considerations and improvements will be discussed.
Date: June 22, 2007
Creator: (NSTec), Nathan Joseph; (NSTec), Aric Tibbits; (NSTec), Ming Wu & (Sandia), Gordon Chandler
Item Type: Article

Understanding the dynamic performance of microchannel plates in pulsed mode

Description: The dynamic performance of a microchannel plate (MCP) is highly dependent on the high-voltage waveforms that are applied to it. Impedance mismatches in MCP detectors can significantly vary the waveforms on the MCP compared to the input pulses. High-voltage pulse waveforms launched onto surface coatings on the MCPs have historically been difficult and expensive to measure. Over the past few years, we have developed and tested techniques utilizing probes to measure the voltage propagation on the surface of MCPs. Square and Gaussian pulses with widths ranging from 200 ps to 2 ns have been applied. We have investigated the effects of coating thickness, microstrip width, and openended versus terminated strips. These data provide a wealth of knowledge that is enabling a better understanding of images recorded with these devices. This presentation discusses a method for measuring voltage profiles on the surface of the MCP and presents Monte Carlo simulations of the optical gate profiles based on the measured waveforms. Excellent agreement in the optical gate profiles have been achieved between the simulations and the experimental measurements using a short-pulse ultraviolet laser.
Date: June 22, 2007
Creator: (NSTec), Ray Thomas; (NSTec), Ming Wu; (NSTec), Nathan Joseph; (NSTec), Craig Kruschwitz & Laboratories), Gregroy A. Rochau (Sandia National
Item Type: Article