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SLAC measurement of the neutron spin structure function

Description: A measurement of the nucleon spin asymmetries from deep inelastic scattering of polarized electrons by polarized [sup 3]He has been performed. The neutron spin structure function g[sub 1][sup n] is extracted and used to test the Bjorken sum rule. The neutron integral assuming a simple Regge theory extrapolation at low x is [integral][sub 0][sup 1]g[sub 1][sup n](x)dx = [minus]0.022 [plus minus] 0.011. Combined with the EMC proton results, the Bjorken sum rule predicts a neutron integral of [int… more
Date: April 1, 1993
Creator: Hughes, E.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Investigation of the coherent synchrotron radiation spectrum as a probe of charge dynamics

Description: Coherent synchrotron, Cherenkov and transition radiation have generated and measured in the far infrared spectral region. This work represents the first identification and separation of the Cherenkov and transition radiation components with transition radiation producing the strongest signal. High-intensity picosecond pulses of radiation are observed for all three sources. The angular dependence in the mm wave region is not the same as that given by high-frequency radiation expressions since th… more
Date: February 1, 1993
Creator: Sievers, A.J. & Tigner, M.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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DNA Radiation Environments Program Spring 1991 2-meter box experiments and analyses. [DEfense Nuclear Agency (DNA)]

Description: This report summarizes the Spring 1991 2-m Box experiments that were performed at the Army Pulse Radiation Facility (APRF) at Aberdeen Proving Ground. These studies were sponsored by the Defense Nuclear Agency (DNA) under the Radiation Environments Program to obtain measured data for benchmarking the Adjoint Monte Carlo Code System, MASH, Version 1.0. The MASH code system was developed for the Department of Defense and NATO for calculating neutron and gamma-ray radiation fields and shielding pr… more
Date: March 1, 1993
Creator: Santoro, R. T. & Whitaker, S. Y.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Experimental studies of free defect generation during irradiation: Implications for reactor environments

Description: Over the past several years, systematic experiments have revealed that irradiations which generate energetically dense cascades are much less effective than light-ion, MeV electron, or thermal neutron irradiations at producing freely-migrating defects. In this paper, the systematic results on freely-migrating defect production from ion irradiation studies are briefly summarized. Difficulties with applying a simple extrapolation of the ion-irradiation results to neutron environments are discusse… more
Date: January 1, 1993
Creator: Rehn, L. E. & Birtcher, R. C.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Workshop on scientific applications of short wavelength coherent light sources

Description: This report contains paper on the following topics: A 2 to 4nm High Power FEL On the SLAC Linac; Atomic Physics with an X-ray Laser; High Resolution, Three Dimensional Soft X-ray Imaging; The Role of X-ray Induced Damage in Biological Micro-imaging; Prospects for X-ray Microscopy in Biology; Femtosecond Optical Pulses ; Research in Chemical Physics Surface Science, and Materials Science, with a Linear Accelerator Coherent Light Source; Application of 10 GeV Electron Driven X-ray Laser in Gamma-… more
Date: February 1, 1993
Creator: Spicer, W.; Arthur, J. & Winick, H.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Radiation hardening and radiation-induced chromium depletion effects on intergranular stress corrosion cracking of austenitic stainless steels

Description: Available data on neutron-irradiated materials have been analyzed and correlations developed between fluence, yield strength, grain boundary chromium concentration and cracking susceptibility in high-temperature water environments. Large heat-to-heat differences in critical fluence (0.2 to 2.5 n/cm[sup 2]) for IGSCC are documented.In many cases, this variability is consistent with yield strength differences among irradiated materials. IGSCC correlated better to yield strength than to fluence fo… more
Date: March 1, 1993
Creator: Bruemmer, S. M. & Simonen, E. P.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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EGS[underscore]Windows2: An enhanced graphical interface to EGS

Description: This report gives a general overview of the EGS[underscore]Windows2 program. The program is intended to be used to display individual particle histories of electrons, photons, and positrons generated by the EGS4 Code System. Much of this work is based on the earlier version of EGS[underscore]Windows2 from the Institute for National Measurement Standards at the National Research Council of Canada (NRCC). No attempt is made to modify their EGS subroutine WATCH, which is used to output the particl… more
Date: January 7, 1993
Creator: Chatterjee, S. (California Univ., Berkeley, CA (United States). Dept. of Electrical Engineering and Computer Science) & Donahue, R.J. (Lawrence Berkeley Lab., CA (United States))
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Nuclear structure studies via neutron interactions. [0 to 20 MeV, dispersive optical model approach]

Description: Comparison has been made between the empirical integrated strengths and external R-functions and the predictions of a dispersive optical model for the n-[sup 208]Pb system, for partial waves through f[sub 7/2]. Parameters of a constant geometry model give a fair representation of the experimental results. A hint of the need for a parity dependence in one of the model parameters is seen in the two data and in thetotal cross section in the low-energy region. Other research performed consisted of:… more
Date: March 1, 1993
Creator: Carlton, R.F.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Neutron sources for a neutron capture therapy facility

Description: Recent advances in the development of boron pharmaceuticals have reopened the possibility of using epithermal neutrons to treat brain tumors containing boron-10. This paper summarizes the approaches being used to generate the neutron sources and identifies specific areas where more research and development are needed.
Date: April 1, 1993
Creator: Lennox, A. J.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Detection of radiation-induced changes in electrochemical properties of austenitic stainless steels using miniaturized specimens and the single-loop electrochemical potentiokinetic reactivation method

Description: Single-loop electrochemical potentiokinetic reactivation testing of miniaturized (TEM) specimens can provide reliable data comparable to data obtained with larger specimens. Significant changes in electrochemical properties (increased reactivation current and Flade potential) were detected for PCA and type 316 stainless steels irradiated at 200--420[degrees]C up to 7--9 dpa. Irradiations in the FFTF Materials Open Test Assembly and in the Oak Ridge Research Reactor are reported on. 45 figs., 5 … more
Date: January 1, 1993
Creator: Inazumi, T.; Bell, G.E.C.; Kenik, E.A. & Kiuchi, K.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Thermophysical properties of saturated light and heavy water for advanced neutron source applications

Description: The Advanced Neutron Source is an experimental facility being developed by Oak Ridge National Laboratory. As a new nuclear fission research reactor of unprecedented flux, the Advanced Neutron Source Reactor will provide the most intense steady-state beams of neutrons in the world. The high heat fluxes generated in the reactor [303 MW(t) with an average power density of 4.5 MW/L] will be accommodated by a flow of heavy water through the core at high velocities. In support of this experimental an… more
Date: May 1, 1993
Creator: Crabtree, A. & Siman-Tov, M.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Design and implementation of low-Q diffractometers at spallation sources

Description: Low-Q diffractometers at spallation sources that use time of flight methods have been successfully implemented at several facilities, including the Los Alamos Neutron Scattering Center. The proposal to build new, more powerful, advanced spallation sources using advanced moderator concepts will provide luminosity greater than 20 times the brightest spallation source available today. These developments provide opportunity and challenge to expand the capabilities of present instruments with new de… more
Date: January 1, 1993
Creator: Seeger, P.A. & Hjelm, R.P.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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[Epithermal neutron capture therapy]

Description: Development of a 4 mA, 2.5 MeV Tandem Cascade Accelerator (TCA) for the production of neutrons via the [sup 7]Li(p,n)[sup 7]Be nuclear reaction is currently nearing completion at SRL. The TCA is a tandem electrostatic accelerator which uses a high current negative ion source in conjunction with a high current solid state cascade multiplier power supply to provide a compact, low cost, proton accelerator capable of supplying multi-milliampere currents at several million electron volts. The inhere… more
Date: January 1, 1993
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Beta and gamma decay heat measurements between 0. 1s--50,000s for neutron fission of [sup 235]U, [sup 238]U and [sup 239]Pu

Description: A helium-jet/tape-transport system is employed in the study of beta-particle and gamma-ray energy spectra of aggregate fission products as a function of time after fission. During the initial nine months of this project we have investigated the following areas: Design, assembly and characterization of a beta-particle spectrometer; Measurement of [sup 235]U(n[sub th]ff) beta spectra for delay times 0.2 s to 12,000 s; Assembly and characterization of a 5 [times] 5 Nal(Tl) gamma-ray spectrometer; … more
Date: January 1, 1993
Creator: Schier, W. A. & Couchell, G. P.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Hybrid S[sub N]/Monte Carlo research and results

Description: The neutral particle transport equation is solved by a hybrid method that iteratively couples regions where deterministic (S[sub N]) and stochastic (Monte Carlo) methods are applied. The Monte Carlo and S[sub N] regions are fully coupled in the sense that no assumption is made about geometrical separation or decoupling. The hybrid Monte Carlo/S[sub N] method provides a new means of solving problems involving both optically thick and optically thin regions that neither Monte Carlo nor S[sub N] i… more
Date: January 1, 1993
Creator: Baker, R.S.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Technical Progress Report: Exotic Atoms

Description: The experiments use a solid hydrogen layer to form muonic hydrogen isotopes that escape into vacuum. The method relies on transfer of the muon from protium to either a deuteron or a triton. The resulting muonic deuterium or muonic tritium will not immediately thermalize because of the very low elastic cross sections, and may be emitted from the surface of the layer. Measurements which detect decay electrons, muonic x-rays, and fusion products have been used to study the processes. A target has … more
Date: January 1, 1993
Creator: Kunselman, R.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Quasi-elastic neutron scattering studies of protein dynamics

Description: Results that shed new light on the study of protein dynamics were obtained by quasi-elastic neutron scattering. The triple axis instrument H-9 supplied by the cold source was used to perform a detailed study of the quasi-elastic spectrum and the Debye-Waller factor for trypsin in powder form, in solution, and in crystals. A preliminary study of myoglobin crystals was also done. A new way to view the results of quasi-elastic scattering experiments is sketched, and the data on trypsin are present… more
Date: May 25, 1993
Creator: Rorschach, H.E.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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TORT certification package

Description: The TORT code has been certified. TORT is a three-dimensional discrete ordinates transport theory code, than can solve neutron, photon, or coupled neutron/photon problems. The code will be used primarily for shielding and radiation field calculations SRS. As defined in this work, certification dies not imply validation. The code must be validated for a particular type of calculation before it can be used for critical applications.
Date: October 1, 1993
Creator: Frost, R. L.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Neutron-induced microstructural alteration of GlidCop{trademark} alloys at 415{degrees}C and high neutron exposure

Description: GlidCop{trademark} internally oxidized copper alloys remain the leading candidates for high heat flux applications in fusion reactor. This paper presents the microstructural changes incurred in three GlidCop{trademark} alloys exposed to long term, high temperature neutron irradiation. Irradiation at high temperature produced a microstructure containing a much lower dislocation density than the unirradiated specimens. Although 10--50 nm size triangular oxide particles were observed in areas with… more
Date: October 1, 1993
Creator: Edwards, D. J.; Garner, F. A.; Newkirk, J. W. & Nadkarni, A.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Microstructural development in irradiated vanadium alloys

Description: Three simple vanadium alloys, V-5Al, V-1Ni, and V-2Ti-1Ni have been examined to determine the effects of fast neutron irradiation on microstructural evolution. Specimens were irradiated in EBR II at temperatures in the range 425 to 600{degrees}C to doses of 15 and 31 dpa. Each alloy responded very differently to irradiation. All V-5Al specimens were generally void-free and contained high densities of coherent precipitates, and moderate densities of network dislocations. Swelling was much higher… more
Date: September 1, 1993
Creator: Gelles, D. S. & Stubbins, J. F.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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High sensitivity, low profile neutron detector for safeguards measurements

Description: A neutron detector has been constructed and tested at Pacific Northwest Laboratory (PNL) for the purpose of making fast, high sensitivity measurements of neutron emitters in portal applications. The system is based upon glass fiber optic scintillators loaded with lithium-6 and operated to detect thermal neutrons. Due to their compact size. physical flexibility, freedom from microphonic pickup, and complete lack of environmental and safety concerns, these fibers are very suitable for some applic… more
Date: December 1, 1993
Creator: Miley, H. S.; Abraham, J. R.; Thompson, R. C. & Sunberg, D. S.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Neutronics and safety characteristics of a 100% MOX fueled PWR using weapons grade plutonium

Description: Preliminary neutronics and safety studies, pertaining to the feasibility of using 100% weapons grade mixed-oxide (MOX) fuel in an advanced PWR Westinghouse design are presented in this paper. The preliminary results include information on boron concentration, power distribution, reactivity coefficients and xenon and control rode worth for the initial and the equilibrium cycle. Important safety issues related to rod ejection and steam line break accidents and shutdown margin requirements are als… more
Date: December 31, 1993
Creator: Biswas, D.; Rathbun, R.; Lee, Si Young & Rosenthal, P.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Preliminary detector design ST862-prototype neutron detector

Description: The detection of fast neutrons has been accomplished with commercially available liquid scintillators in detectors. Liquid scintillators discriminate fast neutrons from gamma radiation by discarding pulses with short decay constants. However, pulse-timing methods require expensive, bulky equipment and a high degree of technical sophistication in the user. Researchers at Pacific Northwest Laboratory have developed a new class of scintillating material, polymerizing crystals of CaF{sub 2}(Eu) and… more
Date: December 1, 1993
Creator: Miller, S. D.; Affinito, J. D. & Sisk, D. R.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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The NE11 experiment at SLAC and the neutron form factors

Description: The neutron electromagnetic form factors G{sub En} and G{sub Mn}, which reflect the charge and magnetization distributions within the neutron, are of fundamental importance for understanding nucleon structure, and are necessary for calculations of processes involving the electromagnetic interaction with complex nuclei. These quantities are functions of Q{sup 2}, the four-momentum transfer squared. SLAC experiment NE11 has measured these form factors out to a Q{sup 2} of 4.0 (GeV/c){sup 2} with … more
Date: May 1, 1993
Creator: Stuart, L. M.; Lung, A. & Bosted, P. E.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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