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Source-jerk analysis using a semi-explicit inverse kinetic technique

Description: A method is proposed for measuring the effective reproduction factor, k, in subcritical systems. The method uses the transient response of a subcritical system to the sudden removal of an extraneous neutron source (i.e., a source jerk). The response is analyzed using an inverse kinetic technique that least-squares fits the exact analytical solution corresponding to a source-jerk transient as derived from the point-reactor model. It has been found that the technique can provide an accurate means… more
Date: January 1, 1985
Creator: Spriggs, G.D. & Pederson, R.A.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Measurement of energy deposited by charged-particle beams in composite targets

Description: We have measured the energy deposited in two types of composite targets by a number of charged-particle beams: targets made of /sup 238/U, Lucite, and polyethylene were exposed to 0.26-GeV protons and 0.33-GeV deuterons, and aluminum-Lucite composites were exposed to 0.5-GeV electrons. In addition, we measured neutrons and gamma rays emitted from solid targets of various materials (including /sup 238/U and iron) exposed to 0.26-GeV protons and 0.33-GeV deuterons. We used passive detectors (ther… more
Date: July 2, 1980
Creator: Farley, E.; Becker, J.; Crase, K.; Howe, R. & Selway, D.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Status of the translawrencium elements (Z > 103)

Description: As a result of conflicting claims to the discovery of the trans-lawrencium elements (Z > 103), IUPAC's Inorganic Chemistry Nomenclature Commission, (II.2), has been incapable of coming to a decision on rightful discoverer for these elements. In addition, the Atomic Weights Commission, (II.1), has from time to time been interested in the status of the search for the superheavy elements, i.e., those elements which might be found in the vicinity of the 'island of stability'. Theoretical studies ha… more
Date: January 1, 1985
Creator: Holden, Norman E.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Background radiation from fission pulses

Description: Extensive source terms for beta, gamma, and neutrons following fission pulses are presented in various tabular and graphical forms. Neutron results from a wide range of fissioning nuclides (42) are examined and detailed information is provided for four fuels: /sup 235/U, /sup 238/U, /sup 232/Th, and /sup 239/Pu; these bracket the range of the delayed spectra. Results at several cooling (decay) times are presented. For ..beta../sup -/ and ..gamma.. spectra, only /sup 235/U and /sup 239/Pu result… more
Date: May 1, 1988
Creator: England, T. R.; Arthur, E. D.; Brady, M. C. & LaBauve, R. J.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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2D PERT. A TWO-DIMENSIONAL PERTURBATION CODE

Description: Given multigroup fluxes and adjoint fluxes of any cylindrical R-Z configuration, 2D PERT may compute: the prompt-neutron lifetime; the relative worth of various delayed neutrons; the integrals of capture, fission, etc., of given materials over any given region; local perturbations, i.e., danger coefflcients; and integrated perturbations, i.e., reactivity effect of uniform variation in the cross sections affecting a whole region. 2D PERT is programmed for a 32K IBM-704 using 3 tape units. The co… more
Date: May 1, 1962
Creator: Chaumont, J. M. & Koerner, J. A.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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THE THEORY AND MEASUREMENT OF CRITICALITY

Description: ABS>The measurable properties of a critical assembly (e.g.. fission, capture, and leakage rates; neutron-per-fission ratios; bare/Cd-covered reaction rate of-atios; danger eoefficients; etc.), whose judicious use completely defines tbcneutron economy in the assembly, are discussed. Require ments regarding the internal consisteney of these of:deasured quantities are reviewed. lt is concluded that theoretical analysis of the assembly must both reproduce the gross experimental results and reflect … more
Date: January 1, 1962
Creator: Kelber, C.N.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Antiproton driven microfission-fusion on closer inspection

Description: A closer look at the energetics of antiproton annihilation in real systems, coupled to hydrodynamics, materials strength, particle transport, equations of state, and related interactions is necessary to assess ultimate viability. The systematics of antiproton microfission-fusion are the subject of this analysis, as well as technology constraints.
Date: January 1, 1992
Creator: Wienke, B.R.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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New fission-neutron-spectrum representation for ENDF

Description: A new representation of the prompt fission neutron spectrum is proposed for use in the Evaluated Nuclear Data File (ENDF). The proposal is made because a new theory exists by which the spectrum can be accurately predicted as a function of the fissioning nucleus and its excitation energy. Thus, prompt fission neutron spectra can be calculated for cases where no measurements exist or where measurements are not possible. The mathematical formalism necessary for application of the new theory within… more
Date: April 1, 1982
Creator: Madland, D.G.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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REACTIVITY CALIBRATIONS AND FISSION-RATE DISTRIBUTIONS IN AN UNMODERATED, UNREFLECTED URANIUM-MOLYBDENUM ALLOY RESEARCH PROGRAM

Description: Completion of zero-power critical experiments with the ORNL Health Physics Research Reactor is reported. A description is given concerning these experiments which were used to determine the critical size, fission-rate distributions, reactivity calibrations of its movable parts, the temperature coefficient of reactivity, and the reactivity effects of the presence of neutron- reflecting materials adjacent to the reactor. (J.R.D.)
Date: May 10, 1962
Creator: Mihalczo, J.T.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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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.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Actinide cross section program at ORELA

Description: The actinide cross section program at ORELA, the Oak Ridge Electron Linear Accelerator, is aimed at obtaining accurate neutron cross sections (primarily fission, capture, and total) for actinide nuclides which occur in fission reactors. Such cross sections, measured as a function of neutron energy over as wide a range of energies as feasible, comprise a data base that permits calculated predictions of the formation and removal of these nuclides in reactors. The present program is funded by the … more
Date: January 1, 1980
Creator: Dabbs, J. W. T.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Absolute measurement of anti. nu. for /sup 252/Cf

Description: Neutron yields were determined by measuring the activities produced in the INEL manganese bath. Of the three fission methods used, the neutron-fission coincidence method was found to be the most consistent and reliable. The value of /sup 252/Cf anti ..nu.. obtained by these measurements was 3.764. (RWR)
Date: January 1, 1980
Creator: Smith, J. R.; Reeder, S. D. & Gehrke, R. J.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Evaluated nuclear data file of Th-232

Description: An evaluated nuclear data file for thorium is described. The file extends over the energy range 0.049 (i.e., the inelastic-scattering threshold) to 20.0 MeV and is formulated within the framework of the ENDF system. The input data base, the evaluation procedures and judgments, and ancillary experiments carried out in conjunction with the evaluation are outlined. The file includes: neutron total cross sections, neutron scattering processes, neutron radiative capture cross sections, fission cross… more
Date: September 1, 1977
Creator: Meadows, J.; Poenitz, W.; Smith, A.; Smith, D.; Whalen, J. & Howerton, R.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Studies of heavy ion reactions and transuranic nuclei. Progress report, August 1, 1979-July 31, 1980. [Univ. of Rochester, New York, 8/1/79-7/31/80]

Description: The study of heavy-ion reaction mechanisms at the SuperHILAC and LAMPF is reported. Preprints of five articles and manuscripts of four recent conference papers are given, along with complete citations of publications and a list of personnel. Significant work was performed in the following areas: the bombarding energy dependence of the /sup 209/Bi + /sup 136/Xe reaction; the fragment yields for specific Z and A for projectile-like fragments produced in the reaction of 8.3-MeV/u /sup 56/Fe ions w… more
Date: July 1, 1980
Creator: Huizenga, J. R.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Average neutronic properties of prompt fission products

Description: Calculations of the average neutronic properties of the ensemble of fission products producted by fast-neutron fission of /sup 235/U and /sup 239/Pu, where the properties are determined before the first beta decay of any of the fragments, are described. For each case we approximate the ensemble by a weighted average over 10 selected nuclides, whose properties we calculate using nuclear-model parameters deduced from the systematic properties of other isotopes of the same elements as the fission … more
Date: February 1, 1982
Creator: Foster, Jr. D. G. & Arthur, E. D.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Nuclear-spectroscopy problems studied with neutrons

Description: Nuclear spectroscopy with neutrons continues to have a major impact on the progress of nuclear science. Neutrons, being uncharged, are particularly useful for the study of low energy reactions. Recent advances in time-of-flight spectroscopy, as well as in the gamma ray spectroscopy following neutron capture, have permitted precision studies of unbound and bound nuclear levels and related phenomena. By going to new energy domains, by using polarized beams and targets, through the invention of ne… more
Date: January 1, 1982
Creator: Raman, S.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Basic research needs in seven energy-related technologies, conservation, conversion, transmission and storage, environmental fission, fossil, geothermal, and solar

Description: This volume comprises seven studies performed by seven groups at seven national laboratories. The laboratories were selected because of their assigned lead roles in research pertaining to the respective technologies. Researches were requested to solicit views of other workers in the fields.
Date: July 1, 1980
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Critical Studies of Dilute Carbide Fast Reactor Core. ZPR-III Assembly 34

Description: Critical studies were made with a simulated, large, dilute power reactor having uranium carbide as fuel. The uranium in the core was 30.7% enriched, and the atomic ratio of uranium to carbon was 0.946. The critical mass was 503.01 kg U/sup 235/ and the critical volume 574.47 liters. Central reactivity coefficients, effective fission crosssection ratios, heterogeneity effects, reactivity worth of distributed materials, foil irradiations, and the average prompt neutron lifetime were measured. Mul… more
Date: May 1961
Creator: Hubert, R. J.; Long, J. K.; McVean, R. L. & Gasidlo, J. M.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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