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DOE OSTI2014

SU-E-T-419: Workflow and FMEA in a New Proton Therapy (PT) Facility

Purpose: Workflow is an important component in the operational planning of a new proton facility. By integrating the concept of failure mode and effect analysis (FMEA) and traditional QA requirements, a workflow for a proton therapy treatment course is set up. This workflow serves as the blue print for the planning of computer hardware/software requirements and network flow. A slight modification of the workflow generates a process map(PM) for FMEA and the planning of QA program in PT. Methods: A flowchart is first developed outlining the sequence of processes involved in a PT treatment course. Each process consists of a number of sub-processes to encompass a broad scope of treatment and QA procedures. For each subprocess, the personnel involved, the equipment needed and the computer hardware/software as well as network requirements are defined by a team of clinical staff, administrators and IT personnel. Results: Eleven intermediate processes with a total of 70 sub-processes involved in a PT treatment course are identified. The number of sub-processes varies, ranging from 2-12. The sub-processes within each process are used for the operational planning. For example, in the CT-Sim process, there are 12 sub-processes: three involve data entry/retrieval from a record-and-verify system, two controlled by the CT computer, two require department/hospital network, and the other five are setup procedures. IT then decides the number of computers needed and the software and network requirement. By removing the traditional QA procedures from the workflow, a PM is generated for FMEA analysis to design a QA program for PT. Conclusion: Significant efforts are involved in the development of the workflow in a PT treatment course. Our hybrid model of combining FMEA and traditional QA program serves a duo purpose of efficient operational planning and designing of a QA program in PT.

07 ISOTOPE AND RADIATION SOURCES↗

DOE OSTI2014

WE-E-19A-01: Globalization of Medical Physics

Following successful 2012–2013 International Professional Symposiums as a part of Annual AAPM meetings, representatives of AAPM and International Organization of Medical Physics (IOMP) suggested to make this tradiational Symposium a permanent part of Annual AAPM meetings in future. Following the tradition, this session includes presentations of representatives of AAPM, IOMP, European Federation of Medical Physics (EFOMP), International Atomic Energy Agency (IAEA) and International Center for Theoretical Physics (ICTP). The speakers will cover various aspects of International collaboration such as educational, professional, and scientific issues, as well as help to developing countries. With further developments of medicine and technology and increased communication with our colleagues overseas, Medical Physics becomes more and more global profession. Use of the same technology, significant progress in medical physics research and developing practical regulations worldwide makes it increasingly useful to organize global collaboration of medical physicists. Several international organizations are tasked to promote such collaboration and provide help to developing countries. Not all AAPM members are fully aware of these international efforts. It is very useful for medical physicists to know about success of our profession in other countries. Different schools present different approaches to the same problem, which allows to find the best solution. By communicating with colleagues overseas, one can learn more than from just reading scientific publications. At this session the attendees will receive a glimpse of International Medical Physics activities. Learning Objectives: Understand the globalization of Medical Physics profession and advantages of collaboration with foreign colleagues. See what role AAPM is playing in establishing contacts with colleagues overseas. Understand the role of IOMP and main directions of its activity. Learn about IAEA and how it helps developing countries. Learn about activity of EFOMP and how can help the global development of Medical Physics. Find out about ICTP and its educational programs.

07 ISOTOPE AND RADIATION SOURCES↗

DOE OSTI2018

Hawthorne Nevada Deep Direct-Use Feasibility Study - References, Reports, Literature

The objective of this project is to use a multi-disciplinary, three-tiered approach to assess the geothermal resource and determine the feasibility of implementing a large-scale, direct-use facility for the Hawthorne Army Depot (HAD) and the various town and county facilities in Hawthorne, Nevada. This assessment directly targets a geothermal resource recently characterized by the Navy Geothermal Program Office (GPO) as part of a focused exploration and development campaign. Data includes: Zip folder containing information from Bjornstad. Includes isotope, temperature, water, well, and reports from 2002; Zip folder contains PDF and power point files of references for the Hawthorne Geothermal project; Zip folder containing PDF files of the literature cited in the proposal.

15 GEOTHERMAL ENERGY↗

DOE OSTI2021

Generation of Bright Soft X-ray Laser Beams (Final Report)

The project goal was to demonstrate new compact soft x-ray lasers emitting high energy ultrashort pulses at shorter wavelengths and increased repetition rates by amplification in atomic transitions in high density laser-created plasmas. To demonstrate these lasers we developed new high power solid state lasers. The project succeeded in demonstrating the shortest wavelength compact soft x-ray laser to date, 6.85 nm wavelength, and the highest repetition rate table-top soft x-ray laser, 400 Hz. We also applied these compact soft x-ray laser sources to determine the composition of materials with nanoscale resolution using a new technique that combines soft x-ray laser ablation with mass spectrometry, and we demonstrated that these lasers are capable of acquiring nanoscale resolution holograms with picosecond time resolution. The combination of an increased pumping efficiency with increased repetition rates can yield soft x-ray laser beams with an unprecedented average power on a table-top for applications demanding a high photon flux. We have demonstrated that the efficiency of plasma-based laser-pumped soft x-ray lasers can be significantly increased by detailed pulse shaping of the pump laser using a new pulse synthesizer. Results include the demonstration of 18.9 nm wavelength laser operation at a record 400 Hz repetition rate, and the extension of repetitive gain-saturated plasma-based table-top x-ray lasers to the shortest wavelength to date, 6.85 nm. Laser amplification was also observed at wavelengths as short at 5.8 nm by isolectronic scaling in Ni-like lanthanide ions. We have also conducted simulations to explore the possibility of demonstrating gain saturated atomic x-ray lasers near the carbon K-edge, in the “carbon window” for the first time. The work conducted under this program also includes the use of compact soft x-ray lasers in applications to problems of chemical interest, such as isotopic composition mapping of micron-size uranium particles with nanoscale resolution, and nanoscale resolution depth profiling analysis of CoNCN-coated electrodes for water oxidation catalysis. We also demonstrated single-shot high resolution soft x-ray Fourier transform holography over a broad 7 µm diameter field of view with ~ 5 ps temporal resolution.

74 ATOMIC AND MOLECULAR PHYSICS↗

DOE OSTI2022

Nuclear Forensics

Nuclear forensics is a key part of the nuclear security strategy for the United States and the international community. The NACS Division is central to the leadership role that LLNL has had in nuclear forensics over the past 25 years. Our current nuclear forensic program includes conducting R&D on provenance and attribution signatures, collaborating with international partners, training the next generation of nuclear forensic experts, developing test materials for verification and validation exercises, and providing expert advice to national and international policy makers. Key to our success in these areas has been the strong and continuing involvement in nuclear forensic casework obtained through law enforcement and intelligence channels as well as our outstanding analytical capabilities. NACS must continue to conduct forward-thinking R&D in nuclear forensics that supports operational programs and addresses intelligence gaps. To maintain leadership in nuclear forensics, we must attract, develop, and retain the best talent. The NNSA has a central leadership role in developing educational initiatives for nuclear forensics. In concert with the Glenn T. Seaborg Institute, the NACS Division will continue to participate in all nuclear forensic educational initiatives (undergraduate, graduate, postdoctoral) and incorporate LLNL’s D&I vision into its student and postdoc recruitment efforts. We will continue to build formal relationships with key academic partners and institutions with active and emerging nuclear forensic research interests. We will also strengthen relationships with NNSA DNN and SSAA funded university consortia (e.g. NSSC, ACE, CNEC, CVT, ETI, MTV), helping them conduct research of interest and relevance to nuclear forensics, while at the same time evaluating and recruiting promising talent from these programs.

07 ISOTOPE AND RADIATION SOURCES↗

DOE OSTI2025

Development of Large Bore Rabbit Capsules in Support of BWR Cladding Irradiations in HFIR

The High Flux Isotope Reactor (HFIR) is an ideal tool for materials irradiation testing because of its intense steady-state neutron flux. Many programs take advantage of HFIR’s central flux trap for irradiation experiments using capsules, also known as rabbits, to support advanced materials development and reactor design. The facility that makes up the HFIR flux trap has recently undergone a design change that increases the HFIR primary coolant volumetric flow rate by removing restrictions in the system. As a result, the usable cross-sectional area within the facility increased, opening the door to increase the cross-sectional area of the rabbit capsules that fill the facility. This report documents a new large-diameter rabbit housing that increases the usable volume within the rabbit capsule by 22.6%. However, challenges arise with increasing the capsule size, such as establishing a new maximum capsule operating pressure and determining the thermal-hydraulic characteristics. This report addresses those challenges with previously adopted HFIR safety methods. The rupture pressure of the rabbit housings is demonstrated while verifying that capsule swelling during and after rupture will not block coolant flow. Then, a safety factor is applied to ascertain an administrative operating pressure. Additionally, the thermal-hydraulic performance of the HFIR facility filled with large-diameter rabbit capsules is shown to not violate previously determined safety criteria. Next, heat transfer coefficients are determined for use in design calculations. Furthermore, this report gives an example of internal configurations for the new, larger rabbit capsules that use relevant boiling water reactor (BWR) cladding geometry. Finally, this report documents an example thermal design performance for a rabbit capsule containing six gauge-curved tensile tube specimens. The thermal performance gives predicted temperature distributions within the capsule and shows the expected temperature of the passive thermometers for post-irradiation temperature comparisons.

99 GENERAL AND MISCELLANEOUS↗

DOE OSTI2025

Development of Large Bore Rabbit Capsules in Support of BWR Cladding Irradiations in HFIR

11 NUCLEAR FUEL CYCLE AND FUEL MATERIALS↗

DOE OSTI2020

Actinide Mixing Optimization Solver

The Actinide Mixing Optimization Solver (AMOS) is a set of programs written in MATLAB that computes theoretical mixes of different uranium, plutonium, thorium, and other actinide materials given a list of isotopic reference materials. Constraints are applied depending on the desired product and a mixture is computed to meet the specified requirements. The optimal mixture consists of a product that uses the lowest possible number of initial actinide materials and has the lowest cost. AMOS is currently applied to particular reference material requests from the sponsoring agency (NNSA) on behalf of the IAEA.

Baldwin, Aaron Taylor↗

DOE OSTI2017

Status of a New Resonance Evaluation for Cerium to Support Nuclear Criticality Safety Applications

A new resonance evaluation is currently being carried out at Oak Ridge National Laboratory (ORNL) for isotopes of cerium. This new evaluation will provide a much-needed update of the resolved and unresolved resonance parameters for {sup 140}Ce and {sup 142}Ce based on new and existing experimental cross section data. The physics of the resolved resonance region will be greatly improved, and new resonance parameter covariance data will be generated. Cerium exists predominately as {sup 140}Ce and {sup 142}Ce and can be found in chemical processing streams because it is used commercially as a catalyst or additive in chemical applications (e.g., glass polishing powder). Cerium has neutron-absorbing properties that can influence the reactivity of systems with fissionable material. The need for improved cerium cross section data has been identified specifically for the Hanford Plutonium Finishing Plant as part of the Nuclear Criticality Safety Program (NCSP) nuclear data request. Furthermore, cerium is a high-yield fission product, making it relevant for reactor calculations. Currently, ENDF/B-VII.1 evaluations for cerium isotopes (described in Section II) do not include the covariance data needed to support sensitivity/uncertainty analyses of systems involving cerium. In addition, the available cerium resonance parameters in ENDF/B-VII.1 are based on parameters provided in the Atlas of Neutron Resonances: Resonance Parameters and Thermal Cross- Sections. Z = 1-100 by S. Mughabghab; hence, the 'evaluated' resonance parameters are not based on a detailed R-matrix analysis. Furthermore, differential measurements are needed in the resonance region to accurately predict the neutron resonances. ORNL has completed new differential measurements on natural samples of cerium, and measurements of an enriched {sup 142}Ce sample are planned. A corresponding resonance evaluation for {sup 140}Ce and {sup 142}Ce being conducted by ORNL will provide detailed cross section resonance parameters and corresponding evaluated covariance data in the resonance region in support of the NCSP. The target uncertainty requested by the NCSP is on the order of 1-2% for the total cross section and less than 6% for the capture cross section in the resolved resonance region. New cerium resonance evaluations will significantly improve radiation transport calculations for systems involving cerium in processes in the DOE Complex. Also, the new evaluations will provide much-needed evaluated covariance data to support sensitivity/ uncertainty analyses.

73 NUCLEAR PHYSICS AND RADIATION PHYSICS↗

DOE OSTI2016

A LIBS method for simultaneous monitoring of the impurities and the hydrogenic composition present in the wall of the TJ-II stellarator

The study of plasma-wall interactions and impurity transport in the plasma fusion devices is critical for the development of future fusion reactors. An experiment to perform laser induced breakdown spectroscopy, using minor modifications of our existing laser blow-off impurity injection system, has been set up thus making both experiments compatible. The radiation produced by the laser pulse focused at the TJ-II wall evaporates a surface layer of deposited impurities and the subsequent radiation produced by the laser-produced plasma is collected by two separate lens and fiber combinations into two spectrometers. The first spectrometer, with low spectral resolution, records a spectrum from 200 to 900 nm to give a survey of impurities present in the wall. The second one, with high resolution, is tuned to the wavelengths of the Hα and Dα lines in order to resolve them and quantify the hydrogen isotopic ratio present on the surface of the wall. The alignment, calibration, and spectral analysis method will be described in detail. First experimental results obtained with this setup will be shown and its relevance for the TJ-II experimental program discussed.

46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND ↗

DOE OSTI2016

Performance testing of a prototype Pd-Ag diffuser

The fusion fuel cycle has gained significant attention over the last decade as interest in fusion programs has increased. One of the critical components of the fusion process is the tritium fuel cycle. The tritium fuel cycle is designed to supply and recycle process tritium at a specific throughput rate. One of the most important processes within the tritium fuel cycle is the clean-up of the of the process tritium. This step will initially separate the hydrogen isotopes (H2, D2, and T2) from the rest of the process gas using Pd-Ag diffusers or permeators. The Pd-Ag diffuser is an integral component for any tritium purification system; whether part of the United States’ defense mission or fusion programs. Domestic manufacturers of Pd-Ag diffusers are extremely limited and only a few manufacturers exist. Johnson-Matthey (JM) Pd-Ag diffusers (permeators) have previously been evaluated for the separation of hydrogen isotopes from non-hydrogen gas species in the process. JM is no longer manufacturing Pd-Ag diffusers and a replacement vendor needs to be identified to support future needs. A prototype Pd-Ag diffuser has been manufactured by Power and Energy, and is considered a potential replacement for the JM diffuser for tritium service. New diffuser designs for a tritium facility for any fusion energy applications must be characterized by evaluating their operating envelope prior to installation in a tritium processing facility. The prototype Pd-Ag diffuser was characterized to determine the overall performance as a function of the permeation of hydrogen through the membrane. The tests described in this report consider the effects of feed gas compositions, feed flow rates, pump configuration and internal tube pressure on the permeation of H2 through the Pd-Ag tubes.

70 PLASMA PHYSICS AND FUSION TECHNOLOGY↗

DOE OSTI2022

Design of the High Rigidity Spectrometer at FRIB

A High Rigidity Spectrometer (HRS) has been designed for experiments at the Facility for Rare-Isotope Beams (FRIB) at Michigan State University (MSU). The HRS will allow experiments to be performed with the most exotic neutron-rich isotopes at high beam energies (≳100 MeV/u). The HRS consists of an analysis beamline called the High-Transmission Beamline (HTBL) and the spectrometer proper called the Spectrometer Section. Here, the maximum magnetic rigidity of the HRS is 8 Tm, which corresponds to the rigidities at which rare-isotope beams are optimally produced at FRIB. The resolving power, angular acceptance, and momentum acceptance are set to match the anticipated scientific program. An ion-optical design developed for the HRS is described in detail, along with the specifications of the associated magnet and detector systems.

73 NUCLEAR PHYSICS AND RADIATION PHYSICS↗

DOE OSTI2016

Status Report on NEAMS PROTEUS/ORIGEN Integration

The US Department of Energy’s Nuclear Energy Advanced Modeling and Simulation (NEAMS) Program has contributed significantly to the development of the PROTEUS neutron transport code at Argonne National Laboratory and to the Oak Ridge Isotope Generation and Depletion Code (ORIGEN) depletion/decay code at Oak Ridge National Laboratory. PROTEUS’s key capability is the efficient and scalable (up to hundreds of thousands of cores) neutron transport solver on general, unstructured, three-dimensional finite-element-type meshes. The scalability and mesh generality enable the transfer of neutron and power distributions to other codes in the NEAMS toolkit for advanced multiphysics analysis. Recently, ORIGEN has received considerable modernization to provide the high-performance depletion/decay capability within the NEAMS toolkit. This work presents a description of the initial integration of ORIGEN in PROTEUS, mainly performed during FY 2015, with minor updates in FY 2016.

22 GENERAL STUDIES OF NUCLEAR REACTORS↗

DOE OSTI2019

The Mk-18A Target Recovery Program: A Collaborative Effort - 19186

The National Nuclear Security Administration (NNSA) Office of Nuclear Materials Integration (OMNI) recently developed a strategy and subsequently developed a project scope for recovering valuable, indispensable radioactive isotopes from Mark-18A (Mk-18A) fuel targets currently stored at the Department of Energy's Savannah River Site. The Savannah River National Laboratory, the Oak Ridge National Laboratory, and OMNI in a joint effort with the Department of Energy-Savannah River Office and the Department of Energy-Office of Science developed a comprehensive plan for the Mk-18A fuel target recovery effort. The cooperation between the various organizations and the direction provided by OMNI allowed this effort to remain focused on the desired final deliverable while accomplishing the early goals both on schedule and within the budget constraints provided by OMNI. To date, specific hardware for the recovery effort has been manufactured, various flowsheets outlining the processing of the materials have been developed, and cooperation between the various organizations is remaining streamlined. The recovery and processing of these targets will provide valuable, unique isotopes for use by various organizations both within the DOE and outside of the DOE. (authors)

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗

DOE OSTI2017

The Los Alamos Neutron Science Center Spallation Neutron Sources

The Los Alamos Neutron Science Center (LANSCE) provides the scientific community with intense sources of neutrons, which can be used to perform experiments supporting civilian and national security research. These measurements include nuclear physics experiments for the defense program, basic science, and the radiation effect programs. This paper focuses on the radiation effects program, which involves mostly accelerated testing of semiconductor parts. When cosmic rays strike the earth's atmosphere, they cause nuclear reactions with elements in the air and produce a wide range of energetic particles. Because neutrons are uncharged, they can reach aircraft altitudes and sea level. These neutrons are thought to be the most important threat to semiconductor devices and integrated circuits. The best way to determine the failure rate due to these neutrons is to measure the failure rate in a neutron source that has the same spectrum as those produced by cosmic rays. Los Alamos has a high-energy and a low-energy neutron source for semiconductor testing. Both are driven by the 800-MeV proton beam from the LANSCE accelerator. The high-energy neutron source at the Weapons Neutron Research (WNR) facility uses a bare target that is designed to produce fast neutrons with energies from 100 keV to almost 800 MeV. The measured neutron energy distribution from WNR is very similar to that of the cosmic-ray-induced neutrons in the atmosphere. However, the flux provided at the WNR facility is typically 5×107 times more intense than the flux of the cosmic-ray-induced neutrons. This intense neutron flux allows testing at greatly accelerated rates. An irradiation test of less than an hour is equivalent to many years of neutron exposure due to cosmic-ray neutrons. The low-energy neutron source is located at the Lujan Neutron Scattering Center. It is based on a moderated source that provides useful neutrons from subthermal energies to ~100 keV. The characteristics of these sources, and ongoing industry program are described in this paper.

07 ISOTOPE AND RADIATION SOURCES↗

DOE OSTI2014

SU-E-I-04: A Mammography Phantom to Measure Mean Glandular Dose and Image Quality

Purpose: To evaluate mean glandular dose (MGD) and image quality in a selection of mammography systems using a novel phantom based on thermoluminescent dosemeters and the ACR wax insert. Methods: The phantom consists of two acrylic, 19 cm diameter, 4.5 cm thick, semicircular modules, used in sequence. The image quality module contains the ACR insert and is used to obtain a quality control image under automatic exposure conditions. The dosimetric module carries 15 TLD-100 chips, some under Al foils, to determine air kerma and half-value-layer. TL readings take place at our laboratory under controlled conditions. Calibration was performed using an ionization chamber and a Senographe 2000D unit for a variety of beam qualities, from 24 to 40 kV, Mo and Rh anodes and filters. Phantom MGD values agree, on the average, within 3% with ionization chamber data, and their precision is better than 10% (k=1). Results: MGD and image quality have been evaluated in a selection of mammography units currently used in Mexican health services. The sample includes analogic (screen/film), flexible digital (CR), and full-field digital image receptors. The highest MDG are associated to the CR technology. The most common image quality failure is due to artifacts (dust, intensifying screen scratches, and processor marks for film/screen, laser reader defects for CR). Conclusion: The developed phantom permits the MGD measurement without the need of a calibrated ionization chamber at the mammography site and can be used by a technician without the presence of a medical physicist. The results indicate the urgent need to establish quality control programs for mammography.

07 ISOTOPE AND RADIATION SOURCES↗

DOE OSTI2023

Characterization of Aluminum Metal Powders for Plutonium-238 Program

As part of radioisotope thermoelectric generator (RTG) production for power sources in deep space exploration, Oak Ridge National Laboratory (ORNL) produces plutonium-238 ( 238 Pu). To produce 238 Pu, neptunium-237 ( 237 Np) targets are fabricated at ORNL and subsequently irradiated at the High Flux Isotope Reactor (HFIR) at ORNL and the Advanced Test Reactor (ATR) at Idaho National Laboratory (INL). Specifically, current flowsheets utilize neptunium dioxide ( 237 NpO 2 ) targets. Aluminum (Al) powder is blended with 237 NpO 2 target material to improve thermal conductivity during irradiation. The current composition of 237 NpO 2 /Al pellets (i.e., cermets, or ceramic–metallics) is 20% 237 NpO 2 , 70% Al, and 10% void space. Al powders utilized by the 238 Pu program are high-fired under vacuum before blending into targets. The primary objective of this work is to measure the physical, chemical, and thermal properties of Al before and after the high-firing process. Properties of interest include the morphology, surface texture, particle size, crystal phase(s), and thermal conductivity of the material. These properties are measured with existing materials characterization equipment at ORNL, including powder x-ray diffraction (pXRD), scanning electron microscopy (SEM) with energy-dispersive spectroscopy (EDS), laser flash analysis (LFA), and thermogravimetric analysis (TGA). A secondary objective of this work is to compare the Al powders before and after the high-firing procedure to determine the effects of high-firing on chemical, physical, and thermal properties and to determine the efficacy of the high-firing process.

11 NUCLEAR FUEL CYCLE AND FUEL MATERIALS↗

DOE OSTI2018

The ARGUS Solution Reactor and Molybdenum Production: A Summary Report Based on Open Literature

The (Aqueous Homogeneous Reactor) AHR was conceptualized at Los Alamos for work in advancing weapon design with initial experiments completed at Los Alamos National Laboratory (LANL) and Oak Ridge National Laboratory (ORNL) in the early 1940s and 1950s. The reactor design was discovered to be an efficient mean of production for medical radio isotopes (e.g. molybdenum-99 and other fission products) due to its streamlined process of extracting target radioactive sources from the fissile solution via a separation system. As the demand for medical radioisotopes has increased so has the need for a safe and low cost isotope source, the most commonly used of which is technetium-99m (99m Tc), daughter product from molybdenum decay. Studies indicate solution reactors pose a significantly lower hazard to the workers, public and environment, compared to other modern reactors (International Atomic Energy Agency 2008). The inherent safety and ability to selectively extract radionuclides from its fuel solution make AHRs particularly well suited for medical isotope production. This discussion narrows its focus to one of the longest running aqueous homogeneous reactor systems, ARGUS. A study of the conversion of ARGUS to a low-enriched uranyl (LEU) sulfate fuel solution was part of the Global Threat Reduction Initiative (GTRI) program. The goal of this paper is to provide a summary of the ARGUS reactor system based on open literature available.

07 ISOTOPE AND RADIATION SOURCES↗