Download or read book Uranium and Plutonium Isotopic Analysis Using MGA written by and published by . This book was released on 1998 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The Lawrence Livermore National Laboratory develops sophisticated gamma-ray analysis codes for the isotopic analysis of nuclear materials based on the principles used in the original MultiGroup Analysis (MGA) code. Over the years, the MGA methodology has been upgraded and expanded far beyond its original capabilities and is now comprised of a suite of codes known as MGA++. The early MGA code analyzed Pu gamma-ray data collected with high-purity germanium (HPGe) detectors to yield Pu isotopic ratios. While the original MGA code relied solely on the lower-energy gamma rays (around 100 keV), the most recent addition to the MGA++ code suite, MGAHI, analyzes Pu data using higher-energy gamma rays (200 keV and higher) and is particulatly useful for Pu samples - that are enclosed in thick-walled containers. The MGA++ suite also includes capabilities to perform U isotopic analysis on data collected with either HPGe or cadmium-zinc-tellutide (CZT) detectors. These codes are commercially available and are known as U235 and CZTU, respectively. A graphical user interface has also been developed for viewing the data and the fitting procedure. In addition, we are developing new codes that will integrate into the MGA++ suite. These will include Pu isotopic analysis capabilities for data collected with CZT detectors, U isotopic analysis with HPGe detectors which utilizes only higher energy gamma rays, and isotopic analyses on mixtures of Pu and U.

Download or read book Plutonium and Uranium Isotopic Analysis written by and published by . This book was released on 1999 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The Lawrence Livermore National Laboratory develops sophisticated gamma-ray analysis codes for isotopic determinations of nuclear materials based on the principles of the MultiGroup Analysis (MGA). MGA methodology has been upgraded and expanded and is now comprised of a suite of codes known as MGA++. A graphical user interface has also been developed for viewing the data and the fitting procedure. The code suite provides plutonium and uranium isotopic analysis for data collected with high-purity germanium planar and/or coaxial detector systems. The most recent addition to the MGA++ code suite, MGAHI, analyzes Pu data using higher-energy gamma rays (200 keV and higher) and is particularly useful for Pu samples that are enclosed in thick-walled containers. Additionally, the code suite can perform isotopic analysis of uranium spectra collected with cadmium-zinc-telluride (CZT) detectors. We are currently developing new codes with will integrate into the MGA++ suite. These will include Pu isotopic analysis capabilities for data collected with CZT detectors, and U isotopic analysis with high-purity germanium detectors, which utilizes only higher energy gamma rays. Future development of MGA++ will include a capability for isotopic analyses on mixtures of Pu and U.

Download or read book High resolution Gamma ray Isotopic Measurements of Uranium Plutonium Samples at IPPE in Support of Physical Inventory Taking Activities written by and published by . This book was released on 1999 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Measurement of various U and Pu samples by gamma-ray spectrometry were performed at the Institute of Physics and Power Engineering to support physical-inventory-taking activities under the Joint US-Russian MPC and A Program. The resulting data was analyzed by several different methods which included Canberra's MGA9.63 (Pu and MOX analysis) and MGAU (U analysis), EG and G Ortec's MGA++ (Pu and MOX analysis) and U235 (U analysis), and FRAM v2.2 (U and Pu analysis) provided by Los Alamos. The results indicate that all of these codes are capable of performing the isotopic analysis adequately. However, some additional modifications may be required to permit better measurement of some of the more unusual components in the Institute of Physics and Power Engineering (IPPE) inventory to meet the demands of inventory-taking activities.

Download or read book Achievements in Testing of the MGA and FRAM Isotopic Software Codes Under the DOE written by and published by . This book was released on 2009 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: DOE/NNSA and IRSN collaborated on a study of gamma-ray instruments and analysis methods used to perform isotopic measurements of special nuclear materials. The two agencies agreed to collaborate on the project in response to inconsistencies that were found in the various versions of software and hardware used to determine the isotopic abundances of uranium and plutonium. IRSN used software developed internally to test the MGA and FRAM isotopic analysis codes for criteria used to stop data acquisition. The stop-criterion test revealed several unusual behaviors in both the MGA and FRAM software codes.

Download or read book Measurement of Plutonium and Uranium Isotopic Abundances by Gamma ray Spectrometry written by and published by . This book was released on 1996 with total page 7 pages. Available in PDF, EPUB and Kindle. Book excerpt: The isotopic composition of plutonium and uranium is needed for purposes of sample confirmation, or for interpreting results from calorimeters or neutron-coincidence measurement instruments to determine nuclear material mass. The authors have developed measurement methods and computer codes utilizing high-resolution gamma-ray spectrometry to measure the relative isotopic abundances of plutonium and uranium in various forms nondestructively. The computer codes, known as MGA and MGAU, have unique analysis methodologies that the authors briefly describe in this paper.

Download or read book Full Range MGA Plutonium Isotopic Analysis Using Single Ge Detector written by and published by . This book was released on 2000 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The Gamma-Ray multi-group analysis code MGA developed at Lawrence Livermore National Laboratory has been widely used in the area of gamma-ray non-destructive plutonium assay. This plutonium isotopic analysis code de-convolutes the complicated, 100-keV x-ray and gamma-ray region to obtain the ratio of Pu isotopes. Calibration of the detector efficiency is not required, but is determined intrinsically from the measured spectra. The code can either analyze low-energy gamma-ray spectrum taken using a high-resolution HPGe detector for energies below 300 keV, or analyze the low-energy spectrum combined with a high-energy spectrum (up to 1 MeV) in the two-detector analysis mode. In the latter case, the use of two detectors has been mandated by the conflicting requirements: excellent resolution at low energies (characteristic of small planar detectors) with good high-energy efficiency (characteristic of coaxial detectors). Usually, a high-energy spectrum taken using a coaxial Ge detector will not provide sufficient energy resolution for 100-keV plutonium isotopic analysis, while the small planar used at low energies has inadequate high-energy efficiency. An optimized-geometry ORTEC HPGe detector has been developed which combines good energy resolution at 100 keV combined with acceptable high-energy ((almost equal to) 1 MeV) efficiency in a single detector. It has been used to gather spectra of both low- and high-energy regions of plutonium spectra simultaneously, for analysis by MGA in the two-detector mode. Five Pu gamma-ray calibration standard sources were used in this study of this special detector.

Download or read book Uranium Isotopic Analysis with the FRAM Isotopic Analysis Code written by and published by . This book was released on 1999 with total page 28 pages. Available in PDF, EPUB and Kindle. Book excerpt: FRAM is the acronym for Fixed-energy Response-function Analysis with Multiple efficiency. This software was developed at Los Alamos National Laboratory originally for plutonium isotopic analysis. Later, it was adapted for uranium isotopic analysis in addition to plutonium. It is a code based on a self-calibration using several gamma-ray peaks for determining the isotopic ratios. The versatile-parameter database structure governs all facets of the data analysis. User editing of the parameter sets allows great flexibility in handling data with different isotopic distributions, interfering isotopes, and different acquisition parameters such as energy calibration and detector type.

Download or read book Experience with a General Gamma Ray Isotopic Analysis Approach written by W. D. Ruhter and published by . This book was released on 2003 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The gamma-ray data analysis methodology originally developed for the MGA code to determine the relative detection efficiency curve may also be used to determine the relative amounts of the isotopes being measured. This analysis approach is based on the fact that the intensity of any given gamma ray from a sample is determined by the amount of the emitting isotope present in the sample, the emission probability for the gamma ray being measured, the sample self attenuation, the attenuation due to absorbers between the sample and detector, and the detector efficiency. An equation can be written that describes a measured gamma-ray peak intensity in terms of these parameters. By selecting appropriate gamma-ray peaks from the isotopes of interest, we can solve a set of equations for the values of the parameters in any particular measurement including the relative amounts of the selected isotopes. The equations representing the peak intensities are very nonlinear and require an iterative least squares method to solve. We have developed software to ensure that during the iterative process the parameters stay within their appropriate ranges and converge properly in solving the set of equations under various measurement conditions. We have utilized and reported on this approach for determining the plutonium isotopic abundances in samples enriched in Pu-238 and to determine the U-235 enrichment of uranium samples in thick-walled containers. Recently, we have used this approach to determine the plutonium isotopic abundances of plutonium samples in thick-walled containers. We will report on this most recent application, and how this general approach can be adapted quickly to any isotopic analysis problem.

Download or read book Isotopic Analysis of Plutonium and Uranium by Mass Spectrometer written by A. H. TURNBULL and published by . This book was released on 1958 with total page 4 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Determination of Uranium and Plutonium Concentrations and Isotopic Abundances written by B. F. Rider and published by . This book was released on 1964 with total page 60 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Modern Approaches to Isotopic Analysis of Uranium written by and published by . This book was released on 1957 with total page 188 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Improvements in the MGA Code Provide Flexibility and Better Error Analysis written by J. Kerr and published by . This book was released on 2005 with total page 8 pages. Available in PDF, EPUB and Kindle. Book excerpt: 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.

Download or read book Standard Reference Materials Uranium Isotopic Standard Reference Materials written by L. E. Garner and published by . This book was released on 1971 with total page 168 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book MGA Analysis of Low Quantity Samples of U and Pu on an Extended rage Gamma ray Detector written by and published by . This book was released on 2007 with total page 8 pages. Available in PDF, EPUB and Kindle. Book excerpt: The IAEA has expressed a need for improved determination of gamma emitting nuclides in environmental samples collected during inspections of nuclear facilities and to use the MGA++ to determine U and Pu concentrations and isotopic compositions when those elements are present in relatively high concentrations. We are addressing the IAEA needs by evaluating the applicability of extended-range germanium detectors (ERG). In this paper we used 1g U isotopic standards and 100ug Pu liquid standards (1) to determine the performance of MGA++ on this special detector and (2) to estimate the amount of U and Pu necessary in the sample for determination of the isotopics via MGA++ within reasonable accuracy for a week of counting time using this ERG detector.

Download or read book The Counting Method of Isotopic Analysis of Uranium written by D. C. Hull and published by . This book was released on 1946 with total page 4 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Evaluations of the 253U 238U Isotope Ratio Through Thick Walled Containers Using the 185 7 KeV and 1001 0 KeV Gamma Rays written by and published by . This book was released on 2001 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The non-destructive determination of isotope ratios (NDA) present in plutonium- and uranium-bearing materials is best accomplished with a MultiGroup Analysis methodology on spectral data obtained with high-resolution germanium detector systems. This methodology is currently employed in codes such as MGA, MGAU or U235. The MGA code, for example, works well on Pu samples and employs a number of isolated spectral lines in the analysis. The algorithm uses Gaussian and Lorentzian peak shapes that are empirically modified to account for various physical and instrumental effects. Additional effects due to external absorbers, sample self-attenuation and detector relative efficiency are also included. Uranium samples are analyzed with MGAU and U235 using a simpler but similar algorithm in the narrow energy range between 85- and 100-keV. Although the details can be complex, the problem described above is ultimately reduced to evaluating a simple ratio. Applied to uranium, for example, one evaluates where the subscripts A and B refer to quantities associated with 235U and 238U, respectively. Specifically, N{sub 235U}/N{sub 238U} is the isotope ratio 235U/238U, I is the measured gamma-ray peak intensity, and E is the counting efficiency, BR is the appropriate branching ratio, t is the appropriate half-life, [alpha]{sup Ab} is an external absorber correction (such as cadmium, iron, etc.) and [beta]{sup U} is a correction for sample self absorption. Indications of other isotopes can, of course, be determined from different ratios evaluated with data from other characteristic gamma rays that may be present in the spectrum.

Download or read book Determination of Pu 239 Th 232 and Natural Uranium Isotopic Concentrations in Biological Samples Using Photofission Track Analysis written by James Roswell Parry and published by . This book was released on 2005 with total page 308 pages. Available in PDF, EPUB and Kindle. Book excerpt: