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Energy dependence of metallic-encapsulated thermoluminescent dosimeters. Annual report

Description: The gamma-ray energy responses of encapsulated /sup 7/LiF and CaF/sub 2/:Mn thermoluminescent dosimeters were measured and compred to calculated values. This study was performed in order to improve the accuracy of gamma-ray heating measurements made in polyenergetic gamma-ray fields such as Argonne National Laboratory's Zero Power Reactors. Equations used in the development of the TERC/III computer code and code input parameters are specified. A section on TLD precision is also included. Compar… more
Date: June 1980
Creator: Simons, G. G.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Radiological survey of the radioactive sands and residues at Lowman, Idaho

Description: No uranium ore milling was performed at the Lowman site, which is located approximately 0.8 km northeast of the town of Lowman, Idaho. Nevertheless, approximately 80,000 metric tons of radioactive sands and residues from upgrading of heavy minerals by physical processing methods remain on the site grounds. Measurements of external gamma radiation 1 m above the surface showed exposure rates up to 2.4 mR/hr on site, but the exposure rate off site quickly dropped to the background level in all dir… more
Date: August 1, 1980
Creator: Haywood, F. F.; Burden, J. E.; Ellis, B. S.; Loy, E. T. & Shinpaugh, W. H.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Weldon Spring quarry construction staging area and water treatment plant site remedial action characterization report for the Weldon Spring Site Remedial Action Project, Weldon Spring, Missouri

Description: The quarry construction staging area (QCSA) and water treatment plant (WTP) are located in the areas that border the western edge of the Weldon Spring quarry (WSQ). These facilities were constructed to support bulk waste removal from the WSQ. This area was contaminated with U-238, Ra-226, and Th-230 and was remediated prior to construction in order to allow release of the area for use without radiological restrictions. This report documents the methods of characterization, the remediation activ… more
Date: September 1, 1991
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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NDA technology for uranium resource evaluation. Progress report July 1-December 31, 1979. [Gamma spectra calculations; field prototype photoneutron logging probe]

Description: This report describes work performed during the time period from July 1, 1979 to December 31, 1979, on the contract for Nondestructive Nuclear Analysis (NDA) Technology for Uranium Resource Evaluation in Group Q-1. Calculational effort was focused on improving the accuracy with which detector response function maps can be generated for subsequent enfolding with ONETRAN angular flux data. Experimental effort was highlighted by a field test of the prototype photoneutron logging probe at the Grand… more
Date: August 1, 1980
Creator: Evans, M.L.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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A PINHOLE CAMERA AUTORADIOGRAPHIC TECHNIQUE FOR ENCAPSULATED IRRADIATED FUEL SPECIMENS

Description: A gamma pinhole camera was devised to permit a nondestructive examination of irradiated specimens while still in sealed capsules. The camera was designed such that a complete experiment may be withdrawn from an irradiation facility, the specimen autoradiographed, and the experiment then reinserted if so desired. The pinhole aperture is 0.020 in., and the source to pinhole block is 4 ft. The image-to-source sizes are a one-to-one ratio. The resolution of the image is 0.03 in. (auth)
Date: April 1, 1962
Creator: Beck, W.N.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Helium/solid powder O-ring leakage correlation experiments using a radiotracer

Description: UO/sub 2/ definitely leaked past the O-ring in three of the tests confirming the major results of the previous work. Continuous leakage at these levels may require additional precautions under present regulatory policies. The mechanism and the time and particle size dependence for the leakage are not known, but there is some indication leakage is more likely at low temperatures. It is possible leakage is due to movement of the O-ring during temperature or pressure cycling at the beginning or en… more
Date: January 1, 1984
Creator: Bild, R. W.; Leisher, W. B.; Weissman, S. H. & Seya, M.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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ION-1 technical manual

Description: The portable gamma-ray and neutron detector electronics (ION-1) gives a digital readout of the current-mode response produced by gamma rays in an ion chamber and of amplification and scaling of pulses received from a neutron detector. The primary application is the measurement of gamma-ray and neutron activity of irradiated reactor fuels stored at a reactor or at a storage pond away from a reactor. ION-1 is the first such instrument to use a design that allows communication of procedures, respo… more
Date: July 1, 1985
Creator: Halbig, J. K. & Caine, J. C.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Minimum detectable activities of contamination control survey equipment

Description: The Instrumentation External Dosimetry (I ED) Section of the Health Physics Department at the Pacific Northwest Laboratory (PNL) has performed a series of tests to determine the ability of portable survey instruments used at Hanford to detect radioactive contamination at levels required by DOE 5480.11. This semi-empirical study combines instrumental, statistical, and human factors as necessary to derive operational detection limits. These threshold detection values have been compared to existin… more
Date: August 1, 1991
Creator: Goles, R. W.; Baumann, B. L. & Johnson, M. L.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Determination of light elements in amalgam restorations. [Dental amalgam]

Description: Rutherford backscattering has been used to measure the major elemental compositions in the near-surface regions of freshly prepared and used samples of dental amalgam. A depletion from bulk stoichiometry of the major elements, which indicates an accumulation of lighter elements on the surface of the materials, has been observed. Increases in the F, Na, Cl, P, O, C, and N concentrations between freshly prepared samples and used samples were measured by observation of gamma rays produced by proto… more
Date: January 1, 1982
Creator: Hanson, A. L.; Jones, K. W.; Kraner, H. W.; Osborne, J. W. & Nelson, G. V.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Limited-angle imaging in positron cameras: theory and practice

Description: The principles of operation of planar positron camera systems made up of multiwire proportional chambers as detectors and electromagnetic delay lines for coordinate readout are discussed. Gamma converters are coupled to the wire chambers to increase detection efficiency and improve spatial resolution. The conversion efficiencies of these converters are calculated and the results compare favorably to the experimentally measured values.
Date: October 1, 1979
Creator: Tam, K.C.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Scintillator spent fuel monitor

Description: A monitor for rapidly measuring the gross gamma-ray flux immediately above spent fuel assemblies in underwater storage racks has been developed. It consists of a plastic scintillator, photomultiplier, collimator, and a small battery-powered electronics package. The crosstalk from an isolated fuel assembly to an adjacent void is only about 2%. The mean difference between the measured gamma-ray flux and the flux estimated from the declared burnup and cooling time with a simple formula is 22%.
Date: January 1, 1980
Creator: Moss, C. E.; Nixon, K. V. & Bernard, W.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Comparison of gamma densitometer detectors used in loss of coolant studies

Description: Ionization chamber type gamma detectors are used in water-steam density measurements in loss of coolant studies at Oak Ridge National Laboratory. Ionization chambers have replaced current-mode scintillation detectors to obtain stability and freedom from magnetic field interference. However, this change results in some loss of fast transient response. Results of studies comparing the transient response of ionization chamber detectors, plastic scintillation detectors, and sodium iodide (NaI) dete… more
Date: January 1, 1979
Creator: Shipp, R.L.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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A comparison of spent fuel assembly control instruments: The Cadarache PYTHON and the Los Alamos Fork

Description: Devices to monitor spent fuel assemblies while stored under water with nondestructive assay methods, have been developed in France and in the United States. Both devices are designed to verify operator's declared values of exposures and cooling-time but the applications and thus the designs of the systems differ. A study, whose results are presented in this paper, has been conducted to compare the features and the performances of the two instruments. 4 refs., 9 figs.
Date: January 1, 1991
Creator: Bignan, G.; Capsie, J.; Romeyer-Dherbey, J. (CEA Centre d'Etudes Nucleaires de Cadarache, 13 - Saint-Paul-lez-Durance (France). Direction des Reacteurs Nucleaires) & Rinard, P. (Los Alamos National Lab., NM (United States))
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Theoretical characterization of a dual-purpose gamma thermometer for local power-generation measurement in an LMFBR

Description: A preliminary analytical and computational study was performed to investigate the potential of a modified gamma thermometer (GT) as both a local power level monitor and a sodium flow blockage monitor for a Liquid Metal Fast Breeder Reactor. This study consisted of two fundamental parts: a radiation field characterization and a thermal-hydraulic analysis. The radiation transport analysis was performed to determine the volumetric heat source within the GT resulting from gamma and neutron heating.… more
Date: April 1, 1982
Creator: Johnson, J. O. & Burns, T. J.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Design and implementation of a fiber-optic gamma-measurement system

Description: The design and implementation of the downhole portion of a measuring system for gamma rays is presented. Included are three alternative designs for radiation-resistant collimating and condensing lenses, sample cells, turning mirrors, and fiber-optic termination techniques. Also discussed are mechanical mounts and positioners, shielding, alignment, test methods, and field installation. Some general design suggestions for optical systems in adverse environments are also presented.
Date: May 19, 1980
Creator: Reedy, R.P.; Crawford, D.W. & Roeske, F. Jr.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Cygnus Experiment at Los Alamos

Description: The Cygnus experiment at Los Alamos National Laboratory has been designed to study, with high angular accuracy, point sources of gamma rays of energy above 10/sup 14/ eV. The experimental detector consists of an air shower array to observe gamma-ray showers and a shielded, large-area track detector to study the muon content of the showers. In this paper we present preliminary data from the array and describe its performance. 9 refs., 3 figs.
Date: January 1, 1986
Creator: Dingus, B. L.; Goodman, J. A.; Gupta, S. K.; Talaga, R. L.; Chang, C. Y.; Yodh, G. B. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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A high-efficiency neutron coincidence counter for small samples

Description: The inventory sample coincidence counter (INVS) has been modified to enhance its performance. The new design is suitable for use with a glove box sample-well (in-line application) as well as for use in the standard at-line mode. The counter has been redesigned to count more efficiently and be less sensitive to variations in sample position. These factors lead to a higher degree of precision and accuracy in a given counting period and allow for the practical use of the INVS counter with gamma-ra… more
Date: January 1, 1991
Creator: Miller, M. C.; Menlove, H. O. & Russo, P. A.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Cerenkov radiators for photodiodes

Description: Several materials have been examined for use as Cerenkov converters in front of photodiodes in an effort to find a gamma detector system that has more sensitivity than a Compton detector but makes little sacrifice in bandwidth. Suprasil (fused silica) and UVT Lucite (acrylic) were 10-100 times more sensitive than a Compton detector and provided almost the same bandwidth. Barium fluoride provided almost 1000 times the sensitivity, but with a factor of 3 or 4 reduction in bandwidth. Relative sens… more
Date: January 1, 1982
Creator: Toevs, J. W.; Young, C. S.; Zagarino, P. A. & Seno, R. D.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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The GAMMASPHERE

Description: GAMMASPHERE is one of a new generation of gamma ray detector arrays. It consists of 100 Compton-suppressed large volume Ge detectors. The design goal is to achieve high efficiency and peak-to-total value for four to five fold coincidence experiments. Such high-fold coincidence capability will provide new physics opportunities in areas such as high spins, transfer reactions, giant resonances, and astrophysics. The design of the detector and shield has been developed through extensive simulation … more
Date: January 1, 1991
Creator: Lee, I-Yang.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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