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Determination of 243Am in 244Cm by Gamma Spectroscopy

Description: Gamma spectroscopy with a high resolution Ge(Li) detector is used to determine 243Am by its 74.7-keV gamma transition in solutions containing much higher specific activities of other actinides and fission products. The method is well suited for analytical control of curium process steps because of its simplicity, speed and reliability. This paper discusses the study results.
Date: August 29, 2001
Creator: Wakat, M.A.
Partner: UNT Libraries Government Documents Department

Radiation level assessment of the Dresden-1 decontamination pilot loop

Description: The radionuclide concentrations of the Dresden-1 decontamination pilot loop were determined by gamma spectroscopy. The General Electric Ge(Li)pipe gamma scanning system was utilized to take measurements at eight locations both before and after the pilot demonstration of decontamination process. Dose rate measrurements were taken with a portable gamma monitor at 30 additional locations. The percentage of Co-60 removed was calculated and the results were interpreted.
Date: May 1, 1978
Partner: UNT Libraries Government Documents Department

Gamma densitometer for measuring Pu density in fuel tubes

Description: A fuel-gamma-densitometer (FGD) has been developed to examine nondestructively the uniformity of plutonium in aluminum-clad fuel tubes at the Savannah River Plant (SRP). The monitoring technique is ..gamma..-ray spectroscopy with a lead-collimated Ge(Li) detector. Plutonium density is correlated with the measured intensity of the 208 keV ..gamma..-ray from /sup 237/U (7d) of the /sup 241/Pu (15y) decay chain. The FGD measures the plutonium density within 0.125- or 0.25-inch-diameter areas of the 0.133- to 0.183-inch-thick tube walls. Each measurement yields a density ratio that relates the plutonium density of the measured area to the plutonium density in normal regions of the tube. The technique was used to appraise a series of fuel tubes to be irradated in an SRP reactor. High-density plutonium areas were initially identified by x-ray methods and then examined quantitatively with the FGD. The FGD reliably tested fuel tubes and yielded density ratios over a range of 0.0 to 2.5. FGD measurements examined (1) nonuniform plutonium densities or hot spots, (2) uniform high-density patches, and (3) plutonium density distribution in thin cladding regions. Measurements for tubes with known plutonium density agreed with predictions to within 2%. Attenuation measurements of the 208-keV ..gamma..-ray passage through the tube walls agreed to within 2 to 3% of calculated predictions. Collimator leakage measurements agreed with model calculations that predicted less than a 1.5% effect on plutonium density ratios. Finally, FGD measurements correlated well with x-ray transmission and fluoroscopic measurements. The data analysis for density ratios involved a small correction of about 10% for ..gamma..-shielding within the fuel tube. For hot spot examinations, limited information for this correction dictated a density ratio uncertainty of 3 to 5%.
Date: January 1, 1982
Creator: Winn, W.G.
Partner: UNT Libraries Government Documents Department

Multiplicity and correlated energy of gamma rays emitted in the spontaneous fission of Californium-252

Description: An array of eight high-speed plastic scintillation detectors has been used to infer a mathematical model for the emission multipliciy of prompt gammas in the spontaneous fission of /sup 252/Cf. Exceptional time resolution and coincidence capability permitted the separation of gammas from fast neutrons over a flight path of approximately 10 cm. About 20 different distribution models were tested. The average energy of the prompt gammas is inversely related to the number emitted; however, this inverse relationship is not strong and the total gamma energy does increase with increasing gamma number. An extension of the experiment incorporated a lithium-drifted germanium gamma spectrometer that resolved nearly 100 discrete gammas associated with fission. Of these gammas, some were preferentially associated with fission in which few gammas were emitted. Certain others were more frequent when many gammas were emitted. Results are presented.
Date: June 1, 1982
Creator: Brunson, G.S. Jr.
Partner: UNT Libraries Government Documents Department

Computer-controlled on-line gamma analysis for krypton-85

Description: /sup 85/Kr will be evolved from spent nuclear fuel during both the voloxidation and dissolution processes, so a reliable method for on-line analysis of /sup 85/Kr in the off-gas system is needed. Tritium, /sup 14/C, and /sup 129/I were trapped, and the activity of /sup 85/Kr was then measured using a Li-drifted Ge detector. Equipment used to carry out this analysis is described; the PET computer is used. The /sup 85/Kr evolution rate was correlated with the fuel dissolution rate; the close correlation permits one to monitor the fuel dissolution process. 11 figures. (DLC)
Date: March 1, 1980
Creator: Canuette, R.P.
Partner: UNT Libraries Government Documents Department

Measurements of the PLT and PDX device activation

Description: Measurements of the activation levels around the PLT and PDX tokamaks have been made using a Ge(Li) gamma spectrometer and a Geiger counter. The activation results from radiation induced in the plasma by 14 MeV neutrons from the d(t,n)..cap alpha.. fusion reaction, 14.7 MeV protons from the d(/sup 3/He,p)..cap alpha.. fusion reaction, 10 ..-->.. 20 MeV hard x-rays from runaway electron induced bremmstrahlung, and 2.5 MeV neutrons from the d(d,n)/sup 3/He fusion reaction. The magnitude of the activation is compared to that predicted for PDX on the basis of one-dimensional activation codes.
Date: September 1, 1981
Creator: Stavely, J.; Barnes, C.W.; Chrien, R.E. & Strachan, J.D.
Partner: UNT Libraries Government Documents Department

Complete system for portable gamma spectroscopy

Description: The report described a system built around the Computing Gamma Spectrometer (PSA) LEA 74-008. The software primarily supports high-resolution gamma-ray spectroscopy using either a high-purity intrinsic germanium detector (HPGe) or a lithium-drifted germanium detector (Ge(Li)).
Date: November 15, 1978
Creator: Fuess, D.A.
Partner: UNT Libraries Government Documents Department

Fast neutron damage in germanium detectors

Description: The effects of fast neutron radiation damage on the performance of both Ge(Li) and Ge(HP) detectors have been studied during the past decade and will be summarized. A review of the interaction processes leading to the defect structures causing trapping will be made. The neutron energy dependence of observable damage effects will be considered in terms of interaction and defect production cross sections.
Date: October 1, 1979
Creator: Kraner, H.W.
Partner: UNT Libraries Government Documents Department

Basic studies of a gas-jet-coupled ion source for on-line isotope separation

Description: A hollow-cathode ion source was used in a gas-jet-coupled configuration to produce ion beams of fission products transported to it from a /sup 252/Cf fission source. Solid aerosols of NaCl and Ag were used effectively as activity carriers in the gas-jet system. Flat-plate skimmers provided an effective coupling of the ion source to the gas jet. Ge(Li) spectrometric measurements of the activity deposited on an ion-beam collector relative to that deposited on a pre-skimmer collector were used to obtain separation efficiencies ranging from 0.1% to > 1% for Sr, Y, Tc, Te, Cs, Ba, Ce, Pr, Nd and Sm. The use of CCl/sub 4/ as a support gas resulted in a significant enhancement of the alkaline-earth and rare-earth separation efficiencies.
Date: January 1, 1980
Creator: Anderl, R.A.; Novick, V.J. & Greenwood, R.C.
Partner: UNT Libraries Government Documents Department

High resolution gamma-ray spectroscopy applied to bulk sample analysis

Description: A high resolution Ge(Li) gamma-ray spectrometer has been installed and made operational for use in routine bulk sample analysis by the Bendix Field Engineering Corporation (BFEC) geochemical analysis department. The Ge(Li) spectrometer provides bulk sample analyses for potassium, uranium, and thorium that are superior to those obtained by the BFEC sodium iodide spectrometer. The near term analysis scheme permits a direct assay for uranium that corrects for bulk sample self-absorption effects and is independent of the uranium/radium disequilibrium condition of the sample. A more complete analysis scheme has been developed that fully utilizes the gamma-ray data provided by the Ge(Li) spectrometer and that more properly accounts for the sample self-absorption effect. This new analysis scheme should be implemented on the BFEC Ge(Li) spectrometer at the earliest date.
Date: January 1, 1980
Creator: Kosanke, K.L.; Koch, C.D. & Wilson, R.D.
Partner: UNT Libraries Government Documents Department

Irradiated-Microsphere Gamma Analyzer (IMGA): an integrated system for HTGR coated particle fuel performance assessment

Description: The Irradiated-Microsphere Gamma Analyzer (IMGA) System, designed and built at ORNL, provides the capability of making statistically accurate failure fraction measurements on irradiated HTGR coated particle fuel. The IMGA records the gamma-ray energy spectra from fuel particles and performs quantitative analyses on these spectra; then, using chemical and physical properties of the gamma emitters it makes a failed-nonfailed decision concerning the ability of the coatings to retain fission products. Actual retention characteristics for the coatings are determined by measuring activity ratios for certain gamma emitters such as /sup 137/Cs//sup 95/Zr and /sup 144/Ce//sup 95/Zr for metallic fission product retention and /sup 134/Cs//sup 137/Cs for an indirect measure of gaseous fission product retention. Data from IMGA (which can be put in the form of n failures observed in N examinations) can be accurately described by the binomial probability distribution model. Using this model, a mathematical relationship between IMGA data (n,N), failure fraction, and confidence level was developed. To determine failure fractions of less than or equal to 1% at confidence levels near 95%, this model dictates that from several hundred to several thousand particles must be examined. The automated particle handler of the IMGA system provides this capability. As a demonstration of failure fraction determination, fuel rod C-3-1 from the OF-2 irradiation capsule was analyzed and failure fraction statistics were applied. Results showed that at the 1% failure fraction level, with a 95% confidence level, the fissile particle batch could not meet requirements; however, the fertile particle exceeded these requirements for the given irradiation temperature and burnup.
Date: February 1, 1980
Creator: Kania, M.J. & Valentine, K.H.
Partner: UNT Libraries Government Documents Department

TPASS: a gamma-ray spectrum analysis and isotope identification computer code

Description: The gamma-ray spectral data-reduction and analysis computer code TPASS is described. This computer code is used to analyze complex Ge(Li) gamma-ray spectra to obtain peak areas corrected for detector efficiencies, from which are determined gamma-ray yields. These yields are compared with an isotope gamma-ray data file to determine the contributions to the observed spectrum from decay of specific radionuclides. A complete FORTRAN listing of the code and a complex test case are given.
Date: March 1, 1981
Creator: Dickens, J.K.
Partner: UNT Libraries Government Documents Department

Applications of in situ gamma-ray spectrometry. [Monitoring radionuclides in soil]

Description: Gamma-ray spectrometric methods using high-resolution Ge(Li) and high purity Ge detectors have been used to quantify the concentrations and external exposure rates of radionuclides in the soil. These in situ methods have been used to study radionuclide deposition around nuclear power stations, the distribution of radionuclides at the Nevada Test Site, biogeochemical cycling of radionuclides, and the fate and impact of fallout radionuclides. Portable gamma-ray spectrometer systems used for various kinds of in situ field measurements include: large-volume coaxial Ge(Li) detectors for terrestrial gamma-ray surveys at several sites including preoperational nuclear power plants and for real-time measurements of nuclear reactor plume isotopic exposure rates; and planar, high purity Ge detectors for mapping /sup 241/Am and /sup 239/Pu soil concentrations, particularly at the Nevada Test Site. These applications are discussed along with a brief description of the methodology and techniques associated with in situ gamma-ray spectrometry.
Date: April 18, 1978
Creator: Ragaini, R.C. & Kirby, J.A.
Partner: UNT Libraries Government Documents Department

Feasibility study for use of a germanium detector in the LOFT gamma-ray densitometer

Description: The primary aim of this study is to predict the performance of a gamma-ray densitometer system using computer modeling techniques. The system consists of a collimated /sup 137/Cs source, a pipe containing a variable amount of water absorber, and a shielded and collimated germanium detector system. The gamma-ray energy spectrum (number of photon counts as a function of energy) has been computed for several sources at the detector. The response for combined sourceconfigurations has been obtained by linear superposition. The signal essentially consists of the counts in an energy window centered on the /sup 137/Cs source at 662 keV that originate from this source. The noise is the background counts in the signal energy window that originate from /sup 16/N scatter radiation and direct and shield tank activation gammas. The detector signal has been computed for 0, 50, and 100 percent water in the pipe. (WHK)
Date: April 27, 1976
Creator: Swierkowski, S. P.
Partner: UNT Libraries Government Documents Department

SAMPO, A Fortran IV Program for Computer Analysis of Gamma Spectrafrom Ge(Li) Detectors, and for Other Spectra with Peaks

Description: SAMPO is a Fortran IV program written to perform the data- reduction analysis described by J. T. Routti and S. G. Prussin in Photopeak Method for the Computer Analysis of Gamma-Ray Spectra from Semiconductor Detectors, Nuclear Instruments and Methods 72, 125-142 (1969). The code has also been used to analyze other spectra with peaks and continua. Program SAMPO can be used for an automatic off-line or an interactive on-line analysis. It includes algorithms for line-shape, energy, and efficiency calibrations, and peak-search and peak-fitting routines. Different options are available to make the code applicable to accurate nuclear spectroscopic work as well as to routine data reduction. The mathematical methods and their coding are briefly described. Instructions for using the program and for preparing input data are given and the optimal strategies for running the code are discussed. Instructions are given for using the LRL program library version of SAMPO and for obtaining source decks.
Date: October 20, 1969
Creator: Routti, Jorma T.
Partner: UNT Libraries Government Documents Department