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The transmission of differing energy beta particles through various materials

Description: The transmission of beta particles is frequently calculated in the same fashion as that of gamma rays, where the mass attenuation coefficient is defined by the slope of the exponential function. Numerous authors have used this approximation including Evans (1955), Loevinger (1952), and Chabot et. al. (1988). Recent work by McCarthy et. al. (1995) indicated that the exponential function seemed to fit well over a particular region of the transmission curve. Upon further investigation, the author decided to verify McCarthy`s results by the use of different absorber materials and attempt to reproduce the experiments. A theoretical method will be used to estimate the transmission of the beta particles through the three absorbers, aluminum, zirconium, and iron. An alternate Monte Carlo code, the Electron Gamma Shower version 4 code (EGS4) will also be used to verify that the experiment is approximating a pencil beam of beta particles. Although these two methods offer a good cross check for the experimental data, they pose a conflict in regards to the type of beam that is to be generated. The experimental lab setup uses a collimated beam of electrons that will impinge upon the absorber, while the codes are written using a pencil beam. A minor discrepancy is expected to be observed in the experimental results and is currently under investigation by McCarthy. The results of this project supported the theory that the beta mass attenuation coefficient was accurately represented by the slope of an exponential function, but only for that particular region of the transmission curve that has a minimal absorber thickness. By fitting the data beyond 50% of the beta particle range this theory does not hold true. The theory generated by McCarthy (1995) and the EGS4 Monte Carlo code indicated that the transmission curve for a pencil beam was not accurately ...
Date: April 1, 1996
Creator: Quayle, D.R.
Partner: UNT Libraries Government Documents Department

A Calculation of the Beta Energy Absorbed by Tritiated Gases in Spherical Vessels

Description: A calculation of tritium beta energy absorption in spherical bulbs filled with mixtures of tritium and other gases is ' carried out under the empirically substantiated assumption that the energy absorption per spherical shell surrounding a point tritium source is representable by a pure exponential function. Primary and successive backscattering at the wall of the vessel is taken into account by means of a very approximate calculation. The computed energy absorption function for hydrogen gas in a silvered bulb agrees within plus or minus 3% over a wide range of gas pressure with the one available set of spherical ionization chamber data. (auth)
Date: May 22, 1961
Creator: Mueller, M M
Partner: UNT Libraries Government Documents Department

HEAT RELEASE IN NUCLEAR REACTORS

Description: Discussions are included on energy sources and modes of local deposition of heat, fission fragment and BETA decay energy, neutron energy, energy release by BETA decay of activated nuclei, neutron flux distribution, gamma heating calculations, and integration of the gamma heating equation for simple cases. (M.H.R.)
Date: October 1, 1956
Creator: Alexander, L.G.
Partner: UNT Libraries Government Documents Department

SUMMARY REPORT ON THE STUDY OF BETA TREATMENT OF URANIUM

Description: A study was made on the effects of beta treatment variables on the texture, grain size, and distortion in unalloyed dingot and ingot uranium. The effects of delta heat treatment, various cooling regimes, recrystallization, etc., were studied. (D.L.C.)
Date: April 1, 1963
Creator: Russell, R.B. & Wolff, A.K.
Partner: UNT Libraries Government Documents Department

COUNTING METHODS FOR THE ASSAY OF RADIOACTIVE SAMPLES

Description: A guide is presented for problems involved in counting methods and techniques used in avoiding or correcting . them. Beta, alpha, and gamma counting is treated. Among the items discussed are the geometry factor, absorption, scattering, and background. A bibliography of 164 references is included. (D.J.C.)
Date: May 1, 1961
Creator: Steinberg, E.P.
Partner: UNT Libraries Government Documents Department

Half-Life for Double Beta-Decay

Description: Fireman(1) has reported the results of a rather difficult beta-particle coincidence counting experiment in which the decay of Sn{sup 124} by the simultaneous emission of two negative beta-particles, with a half-life between 0.4 x 10{sup 16} years and 0.9 x 10{sup 16} years, seems to have been observed. This note reports the results obtained from a different and somewhat simpler method of looking for the phenomenon of simultaneous emission of two beta-particles. These results are negative so far and show that this process is considerably less probable in the case chosen by us than in that reported by Fireman. The method consists of looking in uranium samples for 90-year Pu{sup 238} which would come from U{sup 238} by the double beta-particle mechanism since Np{sup 238} is heavier than U{sup 238}, which in turn is substantially heavier than Pu{sup 238}, in the isobaric triplet {sub 92}U{sup 238}-{sub 93}Np{sup 238}-{sub 94}Pu{sup 238}. This chemical method of investigation is particularly applicable to this isobaric triplet because there appears to be no other mechanisms to account for the Pu{sup 238} should it be found. The energetics of the situation are summarized in the following diagram, where the disintegration energies are derived from sources which may be traced through a recent compilation.
Date: October 21, 1949
Creator: Levine, C.A.; Ghiorso, A. & Seaborg, G.T.
Partner: UNT Libraries Government Documents Department

Studies with Colloids Containing Radioisotopes of Yttrium, Zirconium, Columbium, and Lanthanum: 1. The Chemical Principles and Methods Involved in Preparation of Colloids of Yttrium, Zirconium, Columbium, and Lanthanum

Description: For a number of investigations, including fundamental studies of radiation effects on living tissues and therapeutic utilization of radioisotopes, it is valuable to have methods for the selective localization of radioisotopes in certain tissues. Finely dispersed anhydrous chromic phosphate has been found useful by Jones, Wrobel, and Lyons in selectively irradiating the liver and spleen with p{sup 32} beta particles. The present studies, reported in this and the following communication, are concerned with methods for controlled selective localization of colloids (incorporating radioisotopes) in the liver, spleen, or bone marrow, and with an analysis of some of the factors involved in the phenomenon of localization.
Date: April 21, 1948
Creator: Gofman, John W.
Partner: UNT Libraries Government Documents Department

Acute skin lesions due to localized ``hot particle`` radiation exposures

Description: Purpose of the studies was to determine incidence and severity of lesions resulting from localized deposition of dose to the skin from small (<0.5 mm) discrete radioactive particles. Hanford mini-swine were exposed to localized doses from 0.2 to over 600 Gy (averaged over 1 cm{sup 2} at 70{mu}m depth) from isotopes having max beta particle energies from about 0.3-3 MeV. Incidence of erythema and scabs (indicating ulceration) were scored routinely for up to 71 days post-irradiation. Responses followed normal probability distributions, and thus, no true threshold could be defined. Ten and 50% incidence rates were deduced using probit analyses. Lowest dose producing 10% incidence was about 1 Gy for exposures to Yb-175 (0.5 MeV max energy) beta particles. Severity of lesions was estimated using diameters and persistence. From preliminary considerations of probability of induction, size, and persistence of acute lesions, a special limit for hot particle exposures in the range of 5-50 Gy may be reasonable, with an action level between about 1 Gy and the limit.
Date: June 1, 1996
Creator: Baum, J.W.; Carsten, A.L.; Kaurin, D.G.L. & Schaefer, C.W.
Partner: UNT Libraries Government Documents Department

Testing of the Eberline PCM-2

Description: The PCM-2 manufactured by Eberline Instruments is a whole body monitor that detects both alpha and beta contamination. The PCM-2 uses an IBM compatible personal computer for all software functions. The PCM-2 has 34 large area detectors which can cover approximately 40% of the body at a time. This requires two counting cycles to cover approximately 80% of the body. With the normal background seen at Rocky Flats, each count time takes approximately 15--20 seconds. There are a number of beta and gamma whole body monitors available from different manufacturers, but an alpha whole body monitor is a rarity. Because of the need for alpha whole body monitors at The Rocky Flats Environmental Technology Site, it was decided to do thorough testing on the PCM-2. A three month test was run in uranium building and a three month test in a plutonium building to verify the alpha capabilities of the PCM-2.
Date: December 23, 1994
Creator: Howe, K.L.
Partner: UNT Libraries Government Documents Department

Beta reduction factors for protective clothing at the Oak Ridge National Laboratory

Description: Beta reduction factors (f{sub {beta}}) for protective clothing (PC) at the Oak Ridge National Laboratory (ORNL) have been determined for a variety of protective clothing combinations. Data was collected to determine the experimental f{sub {beta}} for several combinations of PCs under laboratory conditions. Radiation dose rates were measured with an open window Bicron{reg_sign} RSO-5 ion chamber for two distinct beta energy groups (E{sub max} = 1.218 {times} 10{sup {minus}13} J(0.860 MeV) and 3.653 {times} 10{sup {minus}13} J (2.280 MeV)). Data points determined, as the ratio of unattenuated (no PCs) to attenuated (PCs), were used to derive a set of equations using the Microsoft{reg_sign} Excel Linet function. Field comparison tests were then conducted to determine the validity of these beta reduction factors. The f{sub {beta}} from the field tests were significantly less than the experimental f{sub {beta}}, indicating that these factors will yield conservative results.
Date: December 31, 1998
Creator: Franklin, G.L. & Gonzalez, P.L.
Partner: UNT Libraries Government Documents Department

B-Plant D-Filter detector system qualification test report

Description: This report summarizes the results of qualification testing of the B Plant D-Filter Detector System. The purpose of this test was to verify that the system meets the performance requirements and that the unit is ready for field deployment. Testing was performed in the test pit in the 306E Facility. This detector system will be deployed in the B Plant D-Filter to measure beta/gamma dose rates from the filter bank.
Date: August 23, 1996
Creator: Ritter, G.A., Westinghouse Hanford
Partner: UNT Libraries Government Documents Department

Measurement of radionuclides using ion chromatography and flow-cell scintillation counting with pulse shape discrimination

Description: A project has been initiated at Clemson Univ. to develop a HPLC/flow- cell system for analysis of non-gamma emitting radionuclides in environmental samples; an important component is development of a low background flow-cell detector that counts alpha and beta particles separately through pulse shape discrimination. Objective of the work presented here is to provide preliminary results of an evaluation of the following scintillators: CaF{sub 2}:Eu, scintillating glass, and BaF{sub 2}. Slightly acidic aqueous solutions of the alpha emitter {sup 233}U and the beta emitter {sup 45}Ca were used. Detection efficiencies and minimum detectable activities were determined.
Date: December 31, 1995
Creator: DeVol, T.A. & Fjeld, R.A.
Partner: UNT Libraries Government Documents Department

SMEAR STUDY OF D205 (CHEMICAL ENGINEERING BUILDING)

Description: The smear study shows that at least 80% of the floorsmear surveys which were made in a clear area of the Chemical Engineering Building during the course of this study indicated radioactivity equal to or less than 10 d/m/ ft/sup 2/ alpha and equal to or less than 200 d/m/ft/sup 2/ beta-gamma. The smear survey technique is excellent for use in a highhazard area, such as a Pu facility. It is capable of detecting as little as 10 d/m/ft/sup 2/ of alpha contamination with a high degree of confidence. The smear survey is also useful in determining whether the radioactivity on an item is low enough so that it may be removed from an active area. (auth)
Date: July 1, 1962
Creator: Marchetti, F.P.
Partner: UNT Libraries Government Documents Department