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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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Clonal theory of radiation carcinogenesis

Description: In some cases, usually involving high-LET radiations, the dose response at low doses follows a power function of dose with exponent less than one over a wide dose range. This type of response is of great interest since (a) it implies greater effect per unit dose at progressively smaller doses, and (b) it is not predicted by most models and theories of radiobiology. A theoretical framework is presented for responses having the above characteristics over a dose range extending over a factor of 10… more
Date: January 1, 1982
Creator: Baum, J.W.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Sensitivity of primary knock-on atom spectra and displacement per atom cross sections to different secondary neutron energy and angular distributions and ''in-group'' weighting schemes

Description: The sensitivity of primary knock-on atom (PKA) spectra and displacement per atom (DPA) cross sections to different secondary neutron energy and angular distributions and ''in-group'' weighting schemes is investigated. It is shown that the sensitivity of the PKA spectra and DPA cross sections for the (n,n' unresolved) and (n,2n) reactions in Fe to different angular distributions and the same secondary neutron spectrum is reasonably large (approximately 15%), whereas the … more
Date: January 1, 1978
Creator: Gabriel, T. A. & Bishop, B. L.
Item Type: Refine your search to only Report
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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The Advanced Neutron Source

Description: The Advanced Neutron Source (ANS) is a new user experimental facility planned to be operational at Oak Ridge in the late 1990's. The centerpiece of the ANS will be a steady-state research reactor of unprecedented thermal neutron flux ({phi}{sub th} {approx} 9{center dot}10{sup 19} m{sup -2}{center dot}s{sup -1}) accompanied by extensive and comprehensive equipment and facilities for neutron-based research. 5 refs., 5 figs.
Date: January 1, 1989
Creator: Hayter, J. B.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Feasibility of laser pumping with neutron fluxes from present-day large tokamaks

Description: The minimum fusion-neutron flux needed to observe nuclear-pumped lasing with tokamaks can be reduced substantially by optimizing neutron scattering into the laser cell, located between adjacent toroidal-field coils. The laser lines most readily pumped are probably the /sup 3/He-Ne lines at 0.633 ..mu.. and in the infrared, where the /sup 3/He-Ne gas is excited by energetic ions produced in the /sup 3/He(n,p)T reaction. These lines are expected to lase at the levels of D-T neutron flux foreseen … more
Date: August 1, 1986
Creator: Jassby, D. L.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Photodisintegration of /sup 3/H and /sup 3/He. [Threshold to 25 MeV]

Description: The photoneutron cross sections for /sup 3/H and /sup 3/He have been measured from threshold to approx. 25 MeV with monoenergetic photons from the annihilation in flight of fast positrons at the LLL Electron-Positron Linear Accelerator facility. These reactions include the two-body breakup of /sup 3/H and the three-body breakup of both /sup 3/H and /sup 3/He; these measurements for /sup 3/H are the first to span the energy region across the peaks of the cross sections. An efficient BF/sub 3/-tu… more
Date: September 1, 1980
Creator: Faul, D.D.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Radio chemistry as a diagnostic in laser fusion experiments

Description: Nuclear chemistry techniques have been employed in an attempt to measure the density of high compression laser fusion targets. Radioactive /sup 28/Al atoms formed in the /sup 28/Si(n,p)/sup 28/Al reaction arising from the interaction of the 14 MeV neutrons with the silicon atoms in the glass microsphere have been counted at Lawrence Livermore Laboratory using a ..beta..-..gamma.. coincidence method. The detection system that is employed allows activities corresponding to 100 aluminum atoms to b… more
Date: November 1, 1977
Creator: Campbell, E.M.; Hicks, H.G.; Mead, W.C.; Glaros, S.S.; Coleman, L.W. & Laird, W.B.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Particle production and spectra in E802 at BNL-AGS

Description: The production of {pi}, K, and protons measured in the E802 spectrometer are studied for p+A and Si+A collisions. Systematic properties of particle spectra and rapidity density distributions are discussed in terms of centrality and reaction system. A detailed comparison of the data to the RQMD model, which employs the experimental acceptance and cuts are presented. 8 refs., 6 figs.
Date: January 1, 1991
Creator: Videbaek, F.
Item Type: Refine your search to only Article
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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Physics Division Summary Report

Description: The use and operation of the 4.5-Mev Van de Graaff generator ts descrtbed. Sputtering experiments were conducted by bombarding single crystals of electrolytic copper wtth deuterons with energies of 0.8 to 2.5 Mev. The experimental results are discussed on the basis of existing sputtering theories. The kinetic-energy distribution and Boltzmann "temperatures" of most of the fragments of cyanogen under electron impact were determined. A lower limit of 0.05 ev for this temperature'' was also determ… more
Date: January 1, 1962
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Methods and techniques of NDA (nondestructive assay)

Description: Nondestructive assay (NDA) refers to techniques and instruments developed to measure nuclear materials in the many forms in which they occur throughout the fuel cycle. These techniques were first developed to support nuclear safeguards inspections and nuclear material accountability; they are also used extensively for process and quality control. Most accountability measurements are based on analytical chemistry and require that a sample be drawn and analyzed destructively. Destructive analysis… more
Date: January 1, 1988
Creator: Reilly, T. D.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Health physics aspects of nuclear radiations from deuterium beam injectors

Description: Estimations are made for X-ray generation from the accelerator column of various neutral beam injectors. For the case of deuterium beam operation where 2.5-MeV D-D neutrons pose a serious health physics concern, neutron and tritium production rates from beam targets are calculated for different beam energies. Biological doses from these radiations and shielding requirements are discussed.
Date: February 1, 1978
Creator: Kim, J.
Item Type: Refine your search to only Report
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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The Soviet American Gallium Experiment (SAGE)

Description: A radiochemical experiment using the reaction v/sub e/ = /sup 71/Ga + e/sup e/ to determine the integral flux of low-energy neutrinos from the sun is currently under preparation at the Baksan Neutrino Observatory in the USSR. Measurements are scheduled to commence by late 1988 using /approximately/30 tonnes of metallic gallium. With this amount of gallium it should be possible to obtain a fractional statistical accuracy of 12 to 15% after one year (assuming the standard solar model neutrino flu… more
Date: January 1, 1988
Creator: Abazov, A. I.; Abdurashitov, D. N.; Anosov, O. P.; Avdeyev, A. V.; Belousko, Yu. I.; Bychuk, O. V. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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New newtron time-of-flight (NTOF) facilities at the Brookhaven 200-MeV Linac

Description: The installation of a new beam chopper and radio-frequency quadrupole (RFQ) preinjector (750 keV) at the Brookhaven National Laboratory (BNL) 200-MeV Linac will enable single micropulse selection (pulse width <1 ns) with periods ranging from 400 ns to 10 ..mu..s. The standard micropulse intensity is 1.2 X 10/sup 9/ p..mu.. pulse with dc-average beam currents of 50 nA-1 ..mu..A routinely available. The NTOF facilities consists of 30-100 meter flight paths at angles of 0, 12, 30, 45, 90, and 135/… more
Date: January 1, 1988
Creator: Ward, T.E.; Alessi, J.; Brennan, J.; Grand, P.; Lankshear, R.; Snead, C.L. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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JACEE long duration balloon flights

Description: JACEE balloon-borne emulsion chamber detectors are used to observe the spectra and interactions of cosmic ray protons and nuclei in the energy range 1-100A TeV. Experience with long duration mid-latitude balloon flights and characteristics of the detector system that make it ideal for planned Antarctic balloon flights are discussed. 5 refs., 2 figs.
Date: January 1, 1989
Creator: Burnett, T.; Iwai, J.; Lord, J.J.; Strausz, S.; Wilkes, R.J. (Washington Univ., Seattle, WA (USA)); Dake, S. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Radiation standards and calibrations. FY-1981 annual report

Description: The research program encompasses: reviewing calibration standards, regulations, and handbooks; assuring that calibration procedures used are in agreement with technically accepted methods; maintaining basic radioactive sources and instruments that serve as radiological standards; and providing traceability to the National Bureau of Standards where possible. In addition, major efforts are being expended to upgrade the 318 calibration facility. This report focuses on major accomplishments during … more
Date: July 1, 1982
Creator: Roberson, P. L.; Yoder, R. C.; Fox, R. A.; Hooker, C. D.; Hogan, R. T.; Holbrook, K. L. et al.
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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Phonon dispersion relation of uranium nitrate above and below the Neel temperature

Description: Neutron coherent inelastic scattering measurements have been made of the phonon dispersion relation of uranium nitride both above and below the Neel temperature T/sub N/ = 50 K. Within the precision of the measurements, about 1% in frequency and 10% in line width and in scattered neutron intensity, no significant changes in these phonon properties were observed as a function of temperature other than those arising from population factor changes and a small stiffening of the lattice as the tempe… more
Date: January 1, 1977
Creator: Dolling, G; Holden, T M; Evensson, E C; Buyers, W J.L. & Lander, G H
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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Material Considerations in the Design of a Bulk Shield for the Fusion Engineering Device

Description: The FED bulk shield provides protection from high-energy neutrons and gamma rays and removes nuclear heat generated. Bulk shield optimization calculations were conducted using the Los Alamos ONEDANT discrete ordinates and the General Atomic PATH point kernel codes. Six candidate steel alloys were considered.
Date: January 1, 1981
Creator: Kirchner, J. & Engholm, B. A.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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