Improvements in the MGA Code Provide Flexibility and Better Error Analysis

The Multi-Group Analysis (MGA) code is widely used to determine nondestructively the relative isotopic abundances of plutonium by gamma-ray spectrometry. MGA users have expressed concern about the lack of flexibility and transparency in the code. Users often have to ask the code developers for modifications to the code to accommodate new measurement situations, such as additional peaks being present in the plutonium spectrum or expected peaks being absent. We are testing several new improvements to a prototype, general gamma-ray isotopic analysis tool with the intent of either revising or replacing the MGA code. These improvements will give the user the ability to modify, add, or delete the gamma- and x-ray energies and branching intensities used by the code in determining a more precise gain and in the determination of the relative detection efficiency. We have also fully integrated the determination of the relative isotopic abundances with the determination of the relative detection efficiency to provide a more accurate determination of the errors in the relative isotopic abundances. We provide details in this paper on these improvements and a comparison of results obtained with current versions of the MGA code

Lawrence Livermore National Laboratory Safeguards and Security quarterly progress report ending March 31, 1996

LLNL carries out safeguards and security activities for DOE Office of Safeguards and Security (OSS) and other organizations within and outside DOE. LLNL is supporting OSS in 6 areas: safeguards technology, safeguards and materials accountability, computer security--distributed systems, complex-wide access control, standardization of security systems, and information technology and security center. This report describes the activities in each of these areas

Design of standards for nondestructive assay of special nuclear material

Nondestructive assay (NDA) of special nuclear material (SNM) involves a variety of measurement techniques, instruments, and nuclear materials. High-quality measurements require well-characterized SNM standards that represent the expected range of mass, chemical composition, and physical properties of the SNM to be measured. Due to the very limited commercial availability of NDA standards, facilities must usually produce their own standards, both to meet their specific measurement needs and to comply with existing regulations. This paper will describe the current extent to which NDA standards are commercially available. The authors will further describe the types of NDA standards used to calibrate and verify the measurement techniques commonly used in the safeguards of SNM. Several types of NDA standards will be discussed in detail to illustrate the considerations that go into specifying and designing traceable, representative standards for materials accounting measurements

Lawrence Livermore National Laboratory safeguards and security quarterly progress report to the U.S. Department of Energy. Quarter ending September 30, 1996

The paper describes tasks undertaken in each of the following areas: Safeguards technology program (STP); Safeguards and material accountability (SMA); Computer security, distributed systems; Complex-wide access control system (CWAC); and Standardization of security systems (SSS). The STP develops advanced, nondestructive analysis technology for measurement of special nuclear materials. Work focuses on R and D relating to X- and gamma-ray spectrometry and to development of computer codes for interpreting the spectral data obtained by these techniques. The SMA is concerned with four areas: insider protection; material accountability; planning and evaluation; and information security. The Computer Security Technology Center provides expertise and solutions to the many information security problems present in today`s computer systems and networks. Incidents of intrusions, computer viruses, the purposeful replacement of legitimate software for illegal purposes, and similar acts are being addressed by the creation of security software, the delivery of incident response expertise, and research and development into secure systems. The purpose of the CWAC is to develop an approach that will allow visitors to use their DOE standard badge in access control systems throughout the DOE complex. The purpose of the SSS project is to support the standardization of security systems to meet DOE orders and requirements, and to support the DOE in offering relevant security technology and capabilities to Federal standardization efforts

Lawrence Livermore National Laboratory safeguards and security quarterly progress report to the U.S. Department of Energy. Quarter ending September 30, 1996

The paper describes tasks undertaken in each of the following areas: Safeguards technology program (STP); Safeguards and material accountability (SMA); Computer security, distributed systems; Complex-wide access control system (CWAC); and Standardization of security systems (SSS). The STP develops advanced, nondestructive analysis technology for measurement of special nuclear materials. Work focuses on R and D relating to X- and gamma-ray spectrometry and to development of computer codes for interpreting the spectral data obtained by these techniques. The SMA is concerned with four areas: insider protection; material accountability; planning and evaluation; and information security. The Computer Security Technology Center provides expertise and solutions to the many information security problems present in today`s computer systems and networks. Incidents of intrusions, computer viruses, the purposeful replacement of legitimate software for illegal purposes, and similar acts are being addressed by the creation of security software, the delivery of incident response expertise, and research and development into secure systems. The purpose of the CWAC is to develop an approach that will allow visitors to use their DOE standard badge in access control systems throughout the DOE complex. The purpose of the SSS project is to support the standardization of security systems to meet DOE orders and requirements, and to support the DOE in offering relevant security technology and capabilities to Federal standardization efforts

A portable medium-resolution gamma-ray spectrometer and analysis software

There is a strong need for portable radiometric instrumentation that can both accurately confirm the presence of nuclear materials and allow isotopic analysis of radionuclides in the field. To fulfill this need the Safeguards Technology Program at LLNL has developed a hand-held, non-cryogenic, low-power gamma-ray and x-ray measurements and analysis instrument that can both search for and then accurately verify the presence of nuclear materials. We will report on the use of cadmium zinc telluride (CZT) detectors, detector electronics, and the new field-portable instrument being developed. We will also describe the isotopic analysis that allows enrichment measurements to be made accurately in the field. These systems provide capability for safeguards inspection and verification applications and could find application in counter-smuggling operations

U.S./Russian lab-to-lab materials protection, control and accounting program efforts at the Institute of Inorganic Materials. Revision 1

The All-Russian Scientific Research Institute of Inorganic Materials (VNIINM) performs research in nuclear power reactor fuel, spent fuel reprocessing and waste management, materials science of fissionable and reactor structural materials, metallurgy, superconducting materials, and analytical sciences. VNIINM supports the Ministry of Atomic Energy of the Russian Federation (MINATOM) in technologies for fabrication and processing of nuclear fuel. As a participant in the US/Russian Lab-to-Lab nuclear materials protection, control and accounting (MPC and A) program, VNIINM is providing support for measurements of nuclear materials in bulk forms by developing specifications, test and evaluation, certification, and implementation of measurement methods for such materials. In 1996, VNIINM will be working with Brookhaven staff in developing and documenting material control and accounting requirements for nuclear materials in bulk form, Livermore and Los Alamos staff in testing and evaluating gamma-ray spectrometry methods for bulk materials, Los Alamos staff in test and evaluation of neutron-coincidence counting techniques, Oak Ridge staff in accounting of bulk materials with process instrumentation, and Pacific Northwest staff on automating VNIINM`s coulometric titration system. In addition, VNIINM will develop a computerized accounting system for nuclear material within VNIINM and their storage facility. The paper will describe the status of this work and anticipated progress in 1996

Portable microcomputer for the analysis of plutonium gamma-ray spectra. Volume I. Data analysis methodology and hardware description

A portable microcomputer has been developed and programmed for the International Atomic Energy Agency (IAEA) to perform in-field analysis of plutonium gamma-ray spectra. The unit includes a 16-bit LSI-11/2 microprocessor, 32-K words of memory, a 20-character display for user prompting, a numeric keyboard for user responses, and a 20-character thermal printer for hard-copy output of results. The unit weights 11 kg and had dimensions of 33.5 x 30.5 x 23.0 cm. This compactness allows the unit to be stored under an airline seat. Only the positions of the 148-keV /sup 241/Pu and 208-keV /sup 237/U peaks are required for spectral analysis that gives plutonium isotopic ratios and weight percent abundances. Volume I of this report provides a detailed description of the data analysis methodology, operation instructions, hardware, and maintenance and troubleshooting. Volume II describes the software and provides software listings

Quality management of gamma-ray isotopic measurements

Reliable knowledge of the quality or the accuracy and precision of a measurement is important for data evaluation and planning inspection strategies. The auditing of nuclear material accounts requires accepted performance information on the measurements used for the accounting data. It is also important to know what measurement equipment and conditions are necessary to achieve a certain level of quality in the measurement results. Information on the quality of gamma-ray isotopic measurements that can be obtained under various measurement conditions is obtained through inter-comparison exercises, laboratory or field measurement exercises, and tailored laboratory experiments. For these evaluations to be useful, the nuclear materials used in them must have well- characterized isotopic information. In this paper, we discuss measurement equipment and conditions required, reference material standards available and needed, and analysis modification procedures for managing the quality of gamma-ray isotopic measurements

Plutonium isotopic analysis system for plutonium samples enriched in {sup 238}Pu in EP 60/61 and fuel-clad containers. Volume 3, Part 2: Software listings

This software manual is addressed to the Westinghouse Hanford`s Radioisotope Power Systems Facility personnel (programmers and supervisors) who maintain the software on the Pu-238 isotopic analysis system. The document is divided into two parts. Part 1 describes the computer codes that control the system, analyze the spectral data, and determine the relative plutonium abundances. Part 2 contains the software listing of the analysis codes