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in subjects: "Scattering"

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The multipulse Thomson scattering diagnostic on the DIII-D tokamak

This paper describes the design and operation of a 40-spatial channel Thomson scattering system that uses multiple 20 Hz Nd:YAG lasers to measure the electron temperature and density profiles periodically throughout an entire plasma discharge. Interference filter polychromators disperse the scattered light which is detected by silicon avalanche photodiodes. The measurable temperature range from 10 eV to 20 keV and the minimum detectable density is about 2 {times} 10{sup 18} m{sup {minus}3}. Las… more

Date: September 1, 1991

Creator: Carlstrom, T. N.; Campbell, G. L.; DeBoo, J. C.; Evanko, R. G.; Evans, J.; Greenfield, C. M. et al.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

/sup 16/O + /sup 40/Ca inelastic scattering and the elastic scattering wave function

The /sup 16/O + /sup 40/Ca inelastic scattering has been measured at 60-MeV incident energy, and evidence has been found in support of an explicit coupling between direct and elastic channels. The measurements were extended over a large angular range and in particular to very forward angles. The ratio of cross sections between extreme forward and backward angles proved very useful in studying the underlying reaction mechanism.

Date: January 1, 1977

Creator: Rehm, K.E.; Henning, W.; Erskine, J.R. & Kovar, D.G.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Fast-neutron total and scattering cross sections of elemental palladium

Neutron total cross sections of palladium are measured from approx. = 0.6 to 4.5 MeV with resolutions of approx. = 30 to 70 keV at intervals of less than or equal to 50 keV. Differential neutron elastic- and inelastic-scattering cross sections are measured from 1.4 to 3.85 MeV at intervals of 50 to 100 keV and at 10 to 20 scattering angles distributed between approx. = 20 and 160/sup 0/. The experimental results are compared with respective quantities given in ENDF/B-V and used to deduce an opt… more

Date: June 1, 1982

Creator: Smith, A. B.; Guenther, P. T. & Whalen, J. F.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Generation of radiation by intense plasma and e. m. undulators

This program involves the generation of short wavelength optical radiation by intense plasma and e.m. undulators. In this concept a relativistic electron beam is wiggled by either the oscillating electric field of an intense plasma wave, or by a laser beam causing it to radiate. For both types of undulators the designed parameters are a{sub w} > 0.1, N {approximately} 100 and {lambda}{sub w} = 100 {mu}m for plasma wave or 10.6 {mu}m for laser light. This progress report describes the work to-da… more

Date: January 1, 1988

Creator: Joshi, C.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Neutron scattering from solutions: the hydration of lanthanide and actinide ions

The neutron scattering difference method is described and applied to investigations of the aqua rare-earth ions, Nd/sup 3 +/ and Dy/sup 3 +/. Metal-water distances and hydration numbers have been unambiguously determined for these ions' inner coordination spheres. The values of the hydration number, n, of 8.5 +- 0.2 for Nd/sup 3 +/ and 7.4 +- 0.5 for Dy/sup 3 +/, directly support the claim of Spedding et al. that n decreases by one unit across the lanthanide series. The possible application of … more

Date: January 1, 1985

Creator: Hahn, R.L.; Narten, A.H. & Annis, B.K.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Fundamental theory of elastic wave scattering by defects in elastic materials: integral equation methods for application to ultrasonic flaw detection

The use of ultrasonic methods in nondestructive testing depends on the interpretation of the scattering of sound waves by flaws. The theory of elastic waves and their scattering in non-uniform media is developed in detail from first principles, and in generality. Both integral equation and differential methods are discussed, with emphasis on the former. General methods for defining scattering cross sections are presented, and conservation theorems are noted. The Born Approximation to the integr… more

Date: May 1, 1976

Creator: Gubernatis, J.E.; Domany, E.; Krumhansl, J.A. & Huberman, M.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Radiative corrections in SU/sub 2/ x U/sub 1/ LEP/SLC

We show the sensitivity of various experimental measurements to one-loop radiative corrections in SU/sub 2/ x U/sub 1/. Models considered are the standard GSW model as well as extensions of it which include extra quarks and leptons, SUSY and certain technicolor models. The observation of longitudinal polarization is a great help in seeing these effects in asymmetries in e/sup +/e/sup -/ ..-->.. ..mu../sup +/..mu../sup -/, tau/sup +/tau/sup -/ on Z/sup 0/ resonance. 25 refs., 22 figs., 10 tabs.

Date: June 1, 1985

Creator: Lynn, B. W.; Peskin, M. E. & Stuart, R. G.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Magnetic excitations in transition-metal ferromagnets. Recent progress and future prospects on neutron scattering experiments

A review is given on current neutron scattering experiments at Brookhaven National Laboratory on transition-metal ferromagnets Ni, Fe, Pd/sub 2/MnSn and MnSi. The scattering intensity in constant-energy scans, observed above T/sub c/ in all of these materials, exhibited a clear peak at finite momentum transfers. Using a simple scattering function with double-Lorentzian shape, we demonstrate that this peak is a manifestation of simple diffusive spin fluctuations. Experimental results of several … more

Date: January 1, 1984

Creator: Uemura, Y.J.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Investigations of CuInSe sub 2 Thin Films and Contacts

This report describes research into electrical contacts for copper indium diselenide (CuInSe{sub 2}) polycrystalline thin films used for solar cell applications. Molybdenum contacts have historically been the most promising for heterojunction solar cells. This program studied contact stability by investigating thermally induced bilayer reactions between molybdenum and copper, indium, and selenium. Because selenization is widely used to fabricate CuInSe{sub 2} thin films for photovoltaic cells, … more

Date: October 1, 1991

Creator: Nicolet, M. A.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Growth, preparation, and dielectric properties of monodomain single crystal PbTiO sub 3

A method is described for obtaining monodomain PbTiO{sub 3} single crystals with high electrical resistivity (10{sup 10}{Omega} cm) and low dielectric frequency dispersion. The single crystals of PbTiO{sub 3} were grown by flux solution method. Space charge related defects, which result in the large dielectric frequency dispersion, were eliminated by heat treatments. 90{degrees} domains were removed by applying a unidirectional compressive stress along the <100> crystallographic direction. The … more

Date: May 1, 1992

Creator: Li, Z.; Xu, X. Z.; Dai, X. H.; Lam, D. J. & Chan, S. K.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Electron heating and confinemet measurements in EBT-S using Thomson scattering

Thomson scattering of ruby laser light was used to measure electron temperatures and densities in the ELMO Bumpy Torus-Scale (EBT-S) at Oak Ridge National Laboratory. The measurements were made primarily during May 1980, although some were taken during January 1980. The scattering system, which was designed for very low electron density measurements, features a 14-J ruby laser, a high-throughput spectrometer, and 15% quantum efficiency photomultipliers. The measured electron densities lie in th… more

Date: September 1, 1980

Creator: Bighel, L. & Cobble, J. A.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Ceramic microstructures and their elucidation by imaging, diffraction and spectroscopic methods

The development and potential utilization of ceramic materials is dependent on a systematic effort involving processing, characterization and appropriate property measurements. The methods of characterization are numerous and it is important to employ the one that is appropriate to the problem both in terms of its information content and the achievable level of resolution. With the incorporation of fine probe forming capabilities in a transmission electron microscope and the development of rela… more

Date: February 1, 1992

Creator: Kirshnan, K.M.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Ab initio calculations on collisions of low energy electrons with polyatomic molecules

The Kohn variational method is one of simplest, and oldest, techniques for performing scattering calculations. Nevertheless, a number of formal problems, as well as practical difficulties associated with the computation of certain required matrix elements, delayed its application to electron--molecule scattering problems for many years. This paper will describe the recent theoretical and computational developments that have made the complex'' Kohn variational method a practical tool for carryin… more

Date: August 1, 1991

Creator: Rescigno, T. N.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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TRANSIENT RADIATION EFFECTS IN CAPACITORS AND DIELECTRIC MATERIALS

Measurements of dielectric leakage, capacitance, electric strength, andd charge scattering phenomena were performed at the Kukla and Godiva III critical assemblies for tantalum and aluminum electrolytic, wax- and oilimpregnated paper, mylar, mica, and ceramic capacitors, and for mylar and Vitamin B-impregnated paper. Leakage data indicate that gamma induced conductivity in capacitor dielectric varies directly with gamma DELTA , where gamma is the gamma radiation rate and DELTA is 0.9 for mylar,… more

Date: August 15, 1961

Creator: Wicklein, H. W. & Dickhaut, R. H.

Item Type: Book

Partner: UNT Libraries Government Documents Department

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Neutron diffraction study of magnetic order in the ternary superconductor ErMo/sub 6/Se/sub 8/

Synthesis of new classes of ternary superconducting materials has led to compounds which also show a strong tendency toward magnetic order when one of the constituent elements is a rare earth. Powder neutron diffraction data on superconducting (T/sub s/ approximately 6 K) samples of ErMo/sub 6/Se/sub 8/ taken in the temperature range 0.05 to 2.0 K show that magnetic Bragg peaks develop at T/sub M/ = 1.1 K, in agreement with specific heat studies. However, it is not possible to index these new r… more

Date: 1977~

Creator: Lynn, J. W.; Moncton, D. E.; Shirane, G.; Thomlinson, W.; Eckert, J. & Shelton, R. N.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Optical-scattering measurements from 1. 06-. mu. m, 0. 53-. mu. m, and 0. 35-. mu. m laser-heated disk targets

A discussion is presented on scattered light measurements relevant to three of the important parametric instabilities which occur in high intensity laser plasma interactions: stimulated Brillouin scattering (SBS), the two plasmon decay instability (2-..omega../sub pe/), and stimulated Raman scattering (SRS). Most of these experiments were carried out on the ARGUS facility. Its configuration is described for the multiple wavelength experiments, all of which were conducted with one beam illuminat… more

Date: January 1, 1982

Creator: Turner, R. E.; Campbell, E. M.; Phillion, D. W.; Mead, W. C.; Ze, F.; Max, C. et al.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Influence of compositional modifications on the corrosion of iron aluminides of molten nitrate salts

The corrosion of iron-aluminum alloys by molten nitrate salt as a function of aluminum, chromium, and other minor elements has been studied as part of an alloy design effort aimed at the development of a strong, ductile, corrosion-resistant FeAl type of aluminide. Short- term weight change data were used to examine the compositional dependence of the corrosion processes that occurred upon exposure of iron aluminides to highly oxidizing nitrate salts of 650{degrees}C. Corrosion resistance was fo… more

Date: January 1, 1991

Creator: Tortorelli, P. F. & Bishop, P. S.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Recent experimental studies on Hadron showers produced in high energy muon-nucleus interactions

The Fermilab Tevatron Muon Experiment has analyzed the hadron showers of events resulting from the scattering of a muon beam (< E{sub {mu}} > = 490 GeV) off H{sub 2}, D{sub 2} and Xenon targets. The topics which will be discussed are: (1) space-time evolution of the hadronization process; (2) leading hadron distributions in the shadowing region; (3) rates and characteristics of 3-jet events. 23 refs.

Date: May 1, 1992

Creator: Morfin, J.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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High beta capture and mirror confinement of laser produced plasmas. Semiannual report, April 1, 1977--September 30, 1977

The LITE research program is addressing two aspects of mirror confinement physics. ECRH heating of the confined LITE plasma is being investigated as a means for producing a local electrostatic well to trap cold ions within the plasma and provide DCLC stabilization without the energy drain effects obtained with a cold stabilizing stream. Concurrently, the heavy ion beam probe diagnostic being developed in LITE to experimentally measure the space potential within a minimum-B mirror plasma. During… more

Date: September 1, 1977

Creator: Haught, A.F.; Tomlinson, R.G. & Ard, W.B.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Physical characterization of magmatic liquids. [Ultrasonic and Brillouin Scattering Studies of Natural and Synthetic Silicates and Oxides]

This report describes a research project that was conducted from August 15, 1985 to February 28, 1992. The project was based on the ultrasonic studies of natural and synthetic silicate melts, and the study of Brillouin scattering of synthetic silicates and oxides. Measurements of the compressional wave velocity and attenuation can be established using the ultrasonic methods. Temperature dependences of silicates can be established by the Brillouin scattering. (MB)

Date: June 5, 1992

Creator: Manghnani, M.H.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Parity violation in polarized electron scattering

The weak forces are responsible for the decay of radioactive nuclei, and it was in these decay processes where parity non-conservation was first observed. Beta decay occurs through emission of e/sup +/ or e/sup -/ particles, indicating that the weak force can carry charge of both signs, and it was natural to speculate on the existence of a neutral component of the weak force. Even though weak neutral forces had not been observed it was conjectured that a neutral component of weak decay could ex… more

Date: October 1, 1980

Creator: Prescott, Charles Y.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Nonlinear optical properties of new KTiOPO sub 4 isostructures

The atomic structures of the nonlinear optical materials potassium titanyl phosphate (KTiOPO{sub 4}, or KTP) and potassium titanyl arsenate (KTiOAsO{sub 4}) feature one-dimensional channels through which the potassium ions are relatively free to migrate. Ion exchange results when these materials are immersed in molten salts containing alkali metal ions. Sodium, lithium and silver all exchange readily for K{sup +} single crystals of both KTP and KTA to yield the exchanged derivatives Na{sub .95}… more

Date: January 1, 1991

Creator: Phillips, M. L. F.; Harrison, W. T. A. & Stucky, G. D.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Fabrication of a 180/sup 0/ electron scattering facility. Final report, January 2, 1975--January 1, 1978

A system of four dipole magnets to be used for 180/sup 0/ electron scattering studies at the 400 MeV William F. Bates Electron Linear Accelerator of Middleton, Massachusetts was constructed and tested. The first three magnets through which the incident beam passes have similar pole shapes and serve only as beam transport elements. The fourth magnet directs the incident beam onto a target, and also receives and deflects the backscattered electrons into a large magnetic spectrometer operating in … more

Date: January 1, 1978

Creator: Peterson, G A

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Evaluation of an optical microscope method for coal-pyrite/marcasite differentiation

A reflected-polarized light microscope technique for coal marcasite-pyrite differentiation is detailed. Presence of the two minerals was verified by x-ray diffraction analysis. The optical technique produced marcasite content values that were consistently lower than those measured by x-ray diffraction. Although the optical technique produces data that are at best semi-quantitative, it can be used to approximate (+-20%) marcasite concentration in coal without a heavy mineral concentration step.

Date: May 1, 1980

Creator: Sanner, Jr, W. S. & Meteney, D. L.

Item Type: Report

Partner: UNT Libraries Government Documents Department