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Background and Derivation of ANS-5.4 Standard Fission Product Release Model

Description: This background report describes the technical basis for the newly proposed American Nuclear Society (ANS) 5.4 standard, Methods for Calculating the Fractional Release of Volatile Fission Products from Oxide Fuels. The proposed ANS 5.4 standard provides a methodology for determining the radioactive fission product releases from the fuel for use in assessing radiological consequences of postulated accidents that do not involve abrupt power transients. When coupled with isotopic yields, this meth… more
Date: January 29, 2010
Creator: Beyer, Carl E. & Turnbull, Andrew J.
Partner: UNT Libraries Government Documents Department
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Fission Fragment Energy Deposition Efficiency

Description: Technical report describing how to estimate the energy deposition efficiency of the kinetic energy of recoiling fragments from nuclear fission in a chemically reacting system. Since it is not always possible to directly measure the deposition the report describes how to estimate through the aid of fission fragment range data.
Date: March 1962
Creator: Steinberg, Meyer, 1924-
Partner: UNT Libraries Government Documents Department
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Spontaneous Fission of 48

Description: Report discussing an experiment to reinvestigate the spontaneous fission of 48 (Pu-238) in an effort to determine a more accurate value for the spontaneous fission constant that was found in a previous experiment.
Date: December 19, 1949
Creator: Jungerman, John A.
Partner: UNT Libraries Government Documents Department
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Event-by-event study of neutron observables in spontaneous and thermal fission

Description: The event-by-event fission model FREYA is extended to spontaneous fission of actinides and a variety of neutron observables are studied for spontaneous fission and fission induced by thermal neutrons with a view towards possible applications for SNM detection. We have shown that event-by-event models of fission, such as FREYA, provide a powerful tool for studying fission neutron correlations. Our results demonstrate that these correlations are significant and exhibit a dependence on the fission… more
Date: September 14, 2011
Creator: Vogt, R & Randrup, J
Partner: UNT Libraries Government Documents Department
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Event-by-Event Simulation of Induced Fission

Description: We are developing a novel code that treats induced fission by statistical (or Monte-Carlo) simulation of individual decay chains. After its initial excitation, the fissionable compound nucleus may either deexcite by evaporation or undergo binary fission into a large number of fission channels each with different energetics involving both energy dissipation and deformed scission prefragments. After separation and Coulomb acceleration, each fission fragment undergoes a succession of individual (n… more
Date: December 13, 2007
Creator: Vogt, R. & Randrup, J.
Partner: UNT Libraries Government Documents Department
open access

Dispersion of the Neutron Emission in U$sup 235$ Fission

Description: Equations are developed which allow the calculation of the average number of neutrons per U{sup 235} fission from experimental measurements. Experimental methods are described, the results of which give a value of (7.8{+-}0.6){sup 1/2} neutrons per U{sup 235} thermal fission. (D.E.B.)
Date: January 1, 1955
Creator: Feynman, R. P.; de Hoffmann, F. & Serber, R.
Partner: UNT Libraries Government Documents Department
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Fission product yield evaluation for the USA evaluated nuclear data files

Description: An evaluated set of fission product yields for use in calculation of decay heat curves with improved accuracy has been prepared. These evaluated yields are based on all known experimental data through 1992. Unmeasured fission product yields are calculated from charge distribution, pairing effects, and isomeric state models developed at Los Alamos National Laboratory. The current evaluation has been distributed as the ENDF/B-VI fission product yield data set.
Date: October 1, 1994
Creator: Rider, B. F. & England, T. R.
Partner: UNT Libraries Government Documents Department
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Spontaneous fission

Description: The spontaneous fission (SF) of the heaviest actinides and the transactinides is of particular interest because of the dramatic changes in properties observed in the region of the heavy fermion isotopes and for still heavier elements. The existing experimental information on SF properties including half-life systematics, fragment kinetic-energy and mass-yield distributions, prompt neutron emission, and gamma emission will be reviewed. Possibility for extending studies of SF properties to other … more
Date: September 1, 1993
Creator: Hoffman, D. C.
Partner: UNT Libraries Government Documents Department
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Final Progress Report

Description: In this project we have established guidelines for the design on organic chromophores suitable for producing high triplet yields via singlet fission. We have proven their utility by identifying a chromophore of a structural class that had never been examined for singlet fission before, 1,3-diphenylisobenzofuran, and demonstrating in two independent ways that a thin layer of this material produces a triplet yield of 200% within experimental error. We have also designed a second chromophore of a … more
Date: October 31, 2011
Creator: Michl, Josef
Partner: UNT Libraries Government Documents Department
open access

A Revised Version Of A Review Of Nuclear Fission. Part One - Fission Phenomena At Low Energy

Description: This revised version contains material published in the two years since the original report was issued in January 1960. The report covers the history of the discovery of fission, fission theory, and the probability of fission. It discusses the distribution of mass in fission, the distribution of nuclear charge in fission, kinetic energy of fission fragments, and the role of neutrons and gamma rays in fission.
Date: April 1962
Creator: Hyde, Earl K.
Partner: UNT Libraries Government Documents Department
open access

A SURVEY AND EVALUATION OF U$sup 233$ FISSION YIELD DATA

Description: A survey of the pertinent literature was made to ascertain the status of data on U/sup 233/ fission-product yields. The various experimental determinations were evaluated, and the most recent mass-spectrometric results were used as a basis for deriving a set of preferred yields. These yields were compared with values reported in two other recent compilations, and for yields >1%, the three setrs agreed with each other to an average precision of <5%. It was concluded that recent measurements have… more
Date: July 13, 1962
Creator: Ferguson, R.L. & O'Kelley, G.D.
Partner: UNT Libraries Government Documents Department
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EBR-2 Fisson-Product-Source Test No. 1

Description: A fission-product source (FPS) was irradiated in EBR-II to provide data for calibrating the facility's fuel-element rupture detector (FERD), which is a delayed-neutron monitor, and germanium-lithium argon-scanning system (GLASS), a fission-gas-activity monitor. A metal alloy source, Ni-3.2 wt.% uranium, provided quantitative recoil release of the fission-product nuclides. The source alloy, in tubular form, was irradiated as core-region segments of 18 capsules in the FPS subassembly. The irradia… more
Date: August 1978
Creator: Strain, R. V.; Fogle, G. L.; Thresh, H. R.; Heinrich, R. R.; Freyer, R. M.; So, B. Y. C. et al.
Partner: UNT Libraries Government Documents Department
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Report on the Possible Effects on the Surrounding Population of an Assumed Release of Fission Products into the Atmosphere from a 300 Megawatt Nuclear Reactor Located at Lagoona Beach, Michigan

Description: Report issued by the APDA over studies conducted on the release of radioactive particles near Lagoona Beach, Michigan in 1955. "The possible effects on the surrounding population of a release of fission products at the Lagoona Beach site" (p. 1) are discussed. This report includes tables, maps, and illustrations.
Date: July 1957
Creator: Gomberg, Henry J.; Bassett, Thomas; Velez, Carlos & Donnell, Alton P.
Partner: UNT Libraries Government Documents Department
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Theoretical Description of the Fission Process

Description: Advanced theoretical methods and high-performance computers may finally unlock the secrets of nuclear fission, a fundamental nuclear decay that is of great relevance to society. In this work, we studied the phenomenon of spontaneous fission using the symmetry-unrestricted nuclear density functional theory (DFT). Our results show that many observed properties of fissioning nuclei can be explained in terms of pathways in multidimensional collective space corresponding to different geometries of f… more
Date: October 25, 2009
Creator: Nazarewicz, Witold
Partner: UNT Libraries Government Documents Department
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Gamma-ray multiplicity measurement of the spontaneous fission decay of 252Cf in a segmented HPGe/BGO detector array

Description: Coincident {gamma} rays from a {sup 252}Cf source were measured using an array of six segmented high-purity germanium (HPGe) Clover detectors each enclosed by 16 bismuth-germanate (BGO) detectors. The detectors were arranged in a cubic pattern around a 1 {micro}Ci {sup 252}Cf source to cover a large solid angle for {gamma}-ray measurement with a reasonable reconstruction of the multiplicity. Neutron multiplicity was determined in certain cases by identifying the prompt {gamma} rays from individ… more
Date: April 23, 2008
Creator: Bleuel, D L; Bernstein, L A; Burke, J T; Gibelin, J; Heffner, M D; Mintz, J et al.
Partner: UNT Libraries Government Documents Department
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