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in subjects: "Fission"

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

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: Article

Partner: UNT Libraries Government Documents Department

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Status of the translawrencium elements (Z > 103)

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: Article

Partner: UNT Libraries Government Documents Department

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Background radiation from fission pulses

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: Report

Partner: UNT Libraries Government Documents Department

open access

Antiproton driven microfission-fusion on closer inspection

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: Article

Partner: UNT Libraries Government Documents Department

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Actinide cross section program at ORELA

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: Article

Partner: UNT Libraries Government Documents Department

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Absolute measurement of anti. nu. for /sup 252/Cf

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: Article

Partner: UNT Libraries Government Documents Department

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Evaluated nuclear data file of Th-232

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: 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]

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: Report

Partner: UNT Libraries Government Documents Department

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Nuclear-spectroscopy problems studied with neutrons

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: 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

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: Report

Partner: UNT Libraries Government Documents Department

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Potential capabilities at LAMPF to study nuclei far from stability

Feasibility studies have shown that a He-jet activity transport line, with a target chamber placed in the LAMPF main beam line, will provide access to short-lived isotopes of a number of elements that cannot be extracted efficiently for study at any other type of on-line facility. The He-jet technique requires targets thin enough to allow a large fraction of the reaction products to recoil out of the target foils; hence, a very intense incident beam current, such as that uniquely available at L… more

Date: January 1, 1985

Creator: Talbert, W. L. & Bunker, M. E.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Status of fission yield data

In this paper we summarize the current status of the recent US evaluation for 34 fissioning nuclides at one or more neutron incident energies and for spontaneous fission. Currently there are 50 yields sets, and for each we have independent and cumulative yields and uncertainties for approximately 1100 fission products. When finalized the recommended data will become part of Version VI of the US ENDF/B. Other major evaluations in progress that are included in a recently formed IAEA Coordinated R… more

Date: January 1, 1988

Creator: England, T. R. & Blachot, J.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Natural repository analogue program. Progress report, July 1-September 30, 1981

A report on the immobilization of uranium in the earth's crust has been completed. Techniques have been developed to do a comprehensive mass inventory of the Oklo reactor zones. These techniques were applied to a compilation of data from Oklo zones 2 and 3-4. The study shows large deficiencies of neodymium, ruthenium, and mass 99 elements (/sup 99/Tc or /sup 99/Ru) in the reactor zones. The extent of these deficiencies are correlated with the intensity of the nuclear reactions. Analyses of ores… more

Date: March 1, 1982

Creator: Curtis, D.B. (comp.)

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Fission-product energy release for times following thermal-neutron fission of /sup 235/U between 2 and 14000 seconds

Fission-product decay energy-releases rates were measured for thermal-neutron fission of /sup 235/U. Samples of mass 1 to 10 ..mu..g were irradiated for 1 to 100 sec by use of the fast pneumatic-tube facility at the Oak Ridge Research Reactor. The resulting beta- and gamma-ray emissions were counted for times-after-fission between 2 and 14,000 seconds. The data were obtained for beta and gamma rays separately as spectral distributions, N(E/sub ..gamma../) vs E/sub ..gamma../ and N(E/sub beta/) … more

Date: October 1, 1977

Creator: Dickens, J. K.; Emery, J. F.; Love, T. A.; McConnell, J. W.; Northcutt, K. J.; Peelle, R. W. et al.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

FITPULS: a code for obtaining analytic fits to aggregate fission-product decay-energy spectra. [In FORTRAN]

The operation and input to the FITPULS code, recently updated to utilize interactive graphics, are described. The code is designed to retrieve data from a library containing aggregate fine-group spectra (150 energy groups) from fission products, collapse the data to few groups (up to 25), and fit the resulting spectra along the cooling time axis with a linear combination of exponential functions. Also given in this report are useful results for aggregate gamma and beta spectra from the decay of… more

Date: March 1, 1980

Creator: LaBauve, R. J.; George, D. C. & England, T. R.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Evaluation of neutron cross sections for fissile and fertile nuclides in the keV range

Procedures for evaluation of radiative capture, elastic and inelastic processes, and fission in the keV region of neutron energies are described. The use of theoretical tools along with the available ENDF utility codes allows the evaluator to extend and expand upon the experimental data, which are often sparse or discrepant. A few problems with the utility codes are noted, and suggestions, made for improvement and extension. Some ENDF/B-V cross sections for important nuclei are plotted in detai… more

Date: January 1, 1980

Creator: Weston, L.W.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Lecture notes for introduction to nuclear engineering 101

The lecture notes for introductory nuclear engineering are provided for Department of Energy personnel that are recent graduates, transfers from non-nuclear industries, and people with minimum engineering training. The material assumes a knowledge of algebra and elementary calculus. These notes support and supplement a three-hour lecture. The reader is led into the subject from the familiar macroscopic world to the microscopic world of atoms and the parts of atoms called elementary particles. O… more

Date: March 1, 1992

Creator: Fullwood, R. & Cadwell, J.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Neutron multiplicity measurements of Cf and Fm isotopes

Prompt neutrons in coincidence with the two fission fragments from the SF of californium 250, 252, and 254, and fermium 256 and 257 were measured with a 75-cm-diameter, Gd-loaded liquid scintillation counter having a neutron-detection efficiency of about 80%. The kinetic energies of both fission fragments and the number of neutrons for each fission event were recorded. From these data, the fragment masses and kinetic energies, the average number of neutrons per fission, and the neutron multipli… more

Date: January 1, 1977

Creator: Hoffman, D. C.; Ford, G. P.; Balagna, J. P. & Veeser, L. R.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Quantum resonances in physical tunneling

It has recently been emphasized that the probability of quantum tunneling is a critical function of the shape of the potential. Applying this observation to physical systems, we point out that in principal information on potential surfaces can be obtained by studying tunneling rates. This is especially true in cases where only spectral data is known, since many potentials yield the same spectrum. 13 refs., 10 figs., 1 tab.

Date: January 1, 1985

Creator: Nieto, M. M. & Truax, D. R.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Total and spontaneous fission half-lives for americium and curium nuclides

The long-lived nuclides of the americium curium elements are of interest for their use in certain safeguard applications and for nuclear reactor burnup studies in waste management. Recommended values are presented for /sup 241,242m,243/Am, and for /sup 242,243,244,245,246,247,248,250/Cm. These values result from a consistent evaluation of all these half-lives. These preliminary estimates were presented earlier. The uncertainties are provided at the 95% confidence limit for each of the recommend… more

Date: January 1, 1985

Creator: Holden, Norman E.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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A comparison of dose and dose-rate conversion factors from the Soviet Union, United Kingdom, US Department of Energy, and the Idaho National Engineering Laboratory Fusion Safety Program

Several independent data sets of radiological dose and dose-rate conversion factors (DCF/DRCF) have been tabulated or developed by the international community both for fission and fusion safety purposes. This report compares sets from the US Department of Energy, the Soviet Union, and the United Kingdom with those calculated by the Idaho National Engineering Laboratory Fusion Safety Program. The objectives were to identify trends and potential outlying values for specific radionuclides and cont… more

Date: December 1, 1991

Creator: Rood, A.S. & Abbott, M.L.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Annual Report for 1981 to the DOE Office of the Assistant Secretary for Environmental Protection, Safety, and Emergency Preparedness. Part 2. Ecological Sciences. [Lead abstract]

Separate abstracts were prepared for the 38 reports for this Pacific Northwest Laboratory Annual Report for 1981 to the DOE Office of Energy Research. This part dealt with research conducted in the ecological sciences.

Date: February 1, 1982

Creator: Vaughan, B.E.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Actinide integral measurements in the CFRMF and integral tests for ENDF/B-V

Integral capture and/or fission rates have been reported earlier for several actinides irradiated in the fast neutron field of the Coupled Fast Reactivity Measurements Facility (CFRMF). These nuclides include /sup 232/Th, /sup 233/U, /sup 235/U, /sup 238/U, /sup 237/Np, /sup 239/Pu, /sup 240/Pu, /sup 242/Pu, /sup 241/Am and /sup 243/Am. This paper forucses on the utilization of these integral data for testing the respective cross sections on ENDF/B-V. Integral cross sections derived from the me… more

Date: January 1, 1982

Creator: Anderl, R. A.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Cooperation between the US and the USSR in the peaceful uses of atomic energy

The decade of the 1960's saw a marked expansion of cooperation between the United States and the Soviet Union for the peaceful uses of atomic energy. In my opinion, this development constituted one of the most encouraging elements in the international scene. Until 1955 contacts between American and Soviet nuclear scientists were virtually nonexistent, as indeed (after World War II) were US-USSR contacts in other fields except as required in formal intergovernmental relations. Then, in July 1955… more

Date: October 1, 1989

Creator: Seaborg, G. T.

Item Type: Article

Partner: UNT Libraries Government Documents Department