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Church & Synagogue Libraries, Volume XXII, Number 4, January/February 1989

Description: Bimonthly publication of the Church and Synagogue Library Association, containing news and events related to the organization and its members, reviews of books and other materials, and stories of interest to the management of congregational libraries. This issue covers January and February 1989.
Date: 1989-01/1989-02
Creator: Church and Synagogue Library Association
Partner: UNT Libraries Special Collections

Calculating coherent pair production with Monte Carlo methods

Description: We discuss calculations of the coherent electromagnetic pair production in ultra-relativistic hadron collisions. This type of production, in lowest order, is obtained from three diagrams which contain two virtual photons. We discuss simple Monte Carlo methods for evaluating these classes of diagrams without recourse to involved algebraic reduction schemes. 19 refs., 11 figs.
Date: January 1, 1989
Creator: Bottcher, C. & Strayer, M. R.
Partner: UNT Libraries Government Documents Department

High spin spectroscopy for odd-Z nuclei with A approx 160

Description: Experimental routhians, alignments, band crossing frequencies, and the B(M1)/B(E2) ratios of the N = 90 isotones and several light Lu (N = 90--96) isotopes are summarized and discussed in terms of shape changes. This systematic analysis shows a neutron- and proton-number dependent quadrupole and {gamma} deformations for these light rare earth nuclei. The stability of the nuclear deformation with respect to {beta} and {gamma} is also found to be particle-number dependent. Such particle-number dependent shapes can be attributed to the different locations of the proton and neutron Fermi levels in the Nilsson diagrams. Configurations dependent shapes are discussed specially concerning the deformation difference between the proton h{sub 9/2} {1/2}{sup {minus}}(541) and the high-K h{sub 11/2} configurations. The observed large neutron band crossing frequencies in the h{sub 9/2} {1/2}{sup {minus}}(541) configuration support the predicted large deformation of this configuration, but can be reproduced by the self-consistent cranked shell model calculation. Lifetime measurement for {sup 157}Ho, one of the nuclei that show such a large {h bar}{omega}{sub c} in the {1/2}{sup {minus}}(541) band, indicates that deformation difference can only account for 20% of such shift in {h bar}{omega}{sub c}. 55 refs., 12 figs.
Date: January 1, 1989
Creator: Yu, C.-H. (Niels Bohr Inst., Copenhagen (Denmark) Tennessee Univ., Knoxville, TN (USA). Dept. of Physics and Astronomy); Gascon, J.; Hagemann, G. B. (Niels Bohr Inst., Copenhagen (Denmark)) & Garrett, J. D. (Niels Bohr Inst., Copenhagen (Denmark) Oak Ridge National Lab., TN (USA))
Partner: UNT Libraries Government Documents Department

Symmetry violations and rare decays

Description: This constitutes the report of the working group on symmetry violations and rare decays. The next generation of CP violating kaon decay experiments (the 2{pi} and {pi}{sup 0}e{sup +}e{sup {minus}} modes) were considered at the Tevatron and at the proposed Main Injector, effectively building upon the work of the earlier Fermilab Workshop on Physics at the Main Injector. The optimizations for the electromagnetic calorimeter and for background rejection are treated in some detail. Very precise CPT tests in the 2{pi} decay modes are also treated. A sensitive experiment looking for flavor violation at the Main Injector (K{sub L} {yields} {mu}e) is discussed. The significant advantages of possible stretcher and prebooster rings are mentioned. 27 refs., 5 figs., 3 tabs.
Date: January 1, 1989
Creator: Coleman, R.; Bock, G.; Enagonio, J.; Hsiung, B.; Yamanaka, T. (Fermi National Accelerator Lab., Batavia, IL (USA)); Winstein, B. et al.
Partner: UNT Libraries Government Documents Department

BNL high energy heavy ion experiments

Description: This paper discusses the measurement of particle spectra and correlations with good particle identification and with various triggers, such as selection of charged multiplicity, neutral energy and forward energy.
Date: January 1, 1989
Creator: Miake, Yasuo.
Partner: UNT Libraries Government Documents Department

Pulsed electron beam precharger

Description: This is the fifth in a series of contracts and grants exploring the advanced particulate pollution control technology of electron beam precipitation. The chief goal of the current contract is to develop a laboratory scale electron beam precharger using a pulsed electric field to the proof-of-concept stage. Contract tasks leading to the achievement of this goal are generally divided up into two categories: tasks required to bring the Electron Beam Precipitator (EBP) test system up to an operational level for the contract work, and tasks concerning the actual experimental and analytical phase of the study. Not unexpectedly, the early portion of the contract duration will be devoted to the commissioning of the EBP and its many subsystems, while the latter portion will devote itself to testing the new pulsed electron beam precharger.
Date: January 1, 1989
Creator: Finney, W. C. (ed.) & Shelton, W. N.
Partner: UNT Libraries Government Documents Department

The kinetics of sulfation of calcium oxide

Description: Studies of the sulfation rate behavior show an initial fast rate followed by a rate decrease. It is generally agreed that product layer diffusion limitations are the explanation for this behavior. Many investigators tried to model this observed rate change, more or less successfully. No agreement has been reached, however, as to the value of the produce layer diffusivity. Hence, in this work we want to investigate the mechanism of this process. In addition to understanding the initial kinetics, two questions will be focused on. First, we should understand what is diffusing. It appears that the driving force for this diffusion phenomenon is not first order with the SO{sub 2} concentration in the gas. This would indicate that some other, intermediary step is occurring. The second question concerns the composition of the product layer. Different conditions at the start of the reaction were observed to produce different diffusion rates at a later stage. The microscopic appearance of the product layer also appeared to be different.
Date: January 1, 1989
Creator: Sarofim, A. F. & Longwell, J. P.
Partner: UNT Libraries Government Documents Department

Reactivity accidents: A reassessment of the design-basis events

Description: This paper summarizes a study of light water reactor event sequences which have been investigated for their potential to result in reactivity accidents with severe consequences. The study is an outgrowth of the concern which arose after the accident at Chernobyl and was recommended by the report of the US Nuclear Regulatory Commission (NRC) on the implications of that accident (NUREG-1251). The work was done for the NRC to reconfirm or bring into question previous judgments on reactivity events which must be analyzed for licensing. Event sequences were defined and then a probabilistic assessment was completed to estimate the frequency of the reactivity event and/or a deterministic calculation was completed to estimate the consequences to the fuel. Using the results of this analysis, analysis done by others, and a set of screening criteria developed within this study, judgments were made for each sequence as to its importance, and recommendations were made as to whether the NRC ought to be considering the important sequences as part of the design basis or for further, more detailed, investigation. 31 refs., 9 figs., 1 tab.
Date: January 1, 1989
Creator: Diamond, D. J.; Hsu, Chia-Jung; Fitzpatrick, R. & Mirkovic, D.
Partner: UNT Libraries Government Documents Department

The basis spline method and associated techniques

Description: We outline the Basis Spline and Collocation methods for the solution of Partial Differential Equations. Particular attention is paid to the theory of errors, and the handling of non-self-adjoint problems which are generated by the collocation method. We discuss applications to Poisson's equation, the Dirac equation, and the calculation of bound and continuum states of atomic and nuclear systems. 12 refs., 6 figs.
Date: January 1, 1989
Creator: Bottcher, C. & Strayer, M. R.
Partner: UNT Libraries Government Documents Department

Los Alamos LEDCOP Opacity Code

Description: The Los Alamos Light Element (Z {le} 30) Detailed Configuration Opacity Code (LEDCOP), used to calculate opacities in local thermodynamic equilibrium (LTE), has been rewritten to incorporate more detailed atomic physics input. This paper outlines the recent improvements in the code that will provide new Rosseland opacities and, more importantly, better group mean opacities for modern radiation-hydrodynamic codes. The first major area of improvement is the inclusion of a complete set of accurate and internally-consistent Hartree-Fock LS term energies and oscillator strengths for each element. While relatively unimportant for equation of state (EOS), this does provide an improved distribution of line energies and strengths for group mean opacities. Secondly, the code now used Hartree-Fock photoionization cross sections for all ground and excited configurations of all ionization stages. These new cross sections are consistent with the bound-bound oscillator strengths and in many cases their inclusion affects the opacity more than the new LS oscillator strengths. 11 refs., 16 figs.
Date: January 1, 1989
Creator: Magee, N. H. Jr. & Merts, A. L.
Partner: UNT Libraries Government Documents Department

sup 13 C and sup 31 P NMR (Nuclear Magnetic Resonance) studies of prostate tumor metabolism

Description: The current research on prostate cancer by NMR spectroscopy and microscopy will most significantly contribute to tumor diagnosis and characterization only if sound biochemical models of tumor metabolism are established and tested. Prior searches focused on universal markers of malignancy, have to date, revealed no universal markers by any method. It is unlikely that NMRS will succeed where other methods have failed, however, NMR spectroscopy does provide a non-invasive means to analyze multiple compounds simultaneously in vivo. In order to fully evaluate the ability of NMRS to differentiate non-malignant from malignant tissues it is necessary to determine sufficient multiple parameters from specific, well-diagnosed, histological tumor types that, in comparison to normal tissue and non-neoplastic, non-normal pathologies from which the given neoplasm must be differentiated, one has enough degrees of freedom to make a mathematically and statistically significant determination. Confounding factors may consist of tumor heterogeneity arising from regional variations in differentiation, ischemia, necrosis, hemorrhage, inflammation and the presence of intermingled normal tissue. One related aspect of our work is the development of {l brace}{sup 13}C{r brace}-{sup 1}H metabolic imaging of {sup 13}C for metabolic characterization, with enhanced spatial localization (46). This should markedly extend the range of potential clinical NMR uses because the spatial variation in prostate metabolism may prove to be just as important in tumor diagnoses as bulk (volume-averaged) properties themselves. It is our hope that NMRS and spectroscopic imaging will reveal a sound correlation between prostate metabolism and tumor properties that will be clinically straightforward and useful for diagnosis.
Date: January 1, 1989
Creator: Sillerud, L. O.; Halliday, K. R.; Freyer, J. P; Griffey, R. H. & Fenoglio-Preiser, C.
Partner: UNT Libraries Government Documents Department

Collective aspects of charged particle track structure

Description: A plasmon generated by a swift charged particle constitutes a coherent excitation about the particle track. We discuss the representation of collective modes in impact parameter space when created by a swift ion or a fast electron, and the decay of these modes into localized excitations. Several alternative spatial representations are considered. We show that the high spatial resolution found in secondary electron emission measurements with scanning electron microscopy is consistent with the existence of the plasmon as an intermediary between the fast incident electron and the measured secondary electrons. 24 refs., 6 figs.
Date: January 1, 1989
Creator: Basbas, G. (Physical Review Letters, Ridge, NY (USA)); Howie, A. (Cambridge Univ. (UK). Cavendish Lab.) & Ritchie, R. H. (Oak Ridge National Lab., TN (USA) Tennessee Univ., Knoxville, TN (USA). Dept. of Physics)
Partner: UNT Libraries Government Documents Department

Dynamical symmetries for fermions

Description: An introduction is given to the Fermion Dynamical Symmetry Model (FDSM). The analytical symmetry limits of the model are then applied to the calculation of physical quantities such as ground-state masses and B(E{sub 2}) values in heavy nuclei. These comparisons with data provide strong support for a new principle of collective motion, the Dynamical Pauli Effect, and suggest that dynamical symmetries which properly account for the pauli principle are much more persistent in nuclear structure than the corresponding boson symmetries. Finally, we present an assessment of criticisms which have been voiced concerning the FDSM, and a discussion of new phenomena and exotic spectroscopy'' which may be suggested by the model. 14 refs., 8 figs., 4 tabs.
Date: January 1, 1989
Creator: Guidry, M.
Partner: UNT Libraries Government Documents Department

Oxygen electrode in molten carbonate fuel cells

Description: The oxygen reduction reaction on a gold electrode in lithium carbonate melt was investigated to determine the influence of partial pressure of carbon dioxide and temperature on electrode kinetics and oxygen solubility by using cyclic Voltammetry and impedance analysis techniques. During this quarter, the impedance data were analyzed by a Complex Nonlinear Least Square (CNLS) Parameter estimation program to determine the kinetic and the mass transfer related parameters such as charge transfer resistance, double layer capacitance, solution resistance, and Warburg coefficient. The estimated parameters were used to obtain the C0{sub 2} reaction orders and apparent activation energies for the exchange current density and the mass transfer parameter (D{sub o}{sup {1/2}}C{sub o}*).
Date: January 1, 1989
Creator: Dave, B. B.; Srinivasan, S.; White, R. E. & Appleby, A. J.
Partner: UNT Libraries Government Documents Department

Applications of computer modeling to fusion research

Description: Progress achieved during this report period is presented on the following topics: Development and application of gyrokinetic particle codes to tokamak transport, development of techniques to take advantage of parallel computers; model dynamo and bootstrap current drive; and in general maintain our broad-based program in basic plasma physics and computer modeling.
Date: January 1, 1989
Creator: Dawson, J. M.
Partner: UNT Libraries Government Documents Department

Vegetation uptake from burial ground alpha waste trenches

Description: This study was conducted as part of an evaluation of the potential radiological consequences of reinhabiting the SRS burial ground. The objective was to determine the uptake of buried, low-level, transuranic waste from unlined earthen trenches by forest vegetation. Two tree plots were established in 1979. One plot was put over a trench containing alpha waste and the other in an area without trenches. When the tree seedlings were sampled during 1979 and 1980, and analysized for {sup 239}Pu and {sup 238}Pu, there was only a small difference in radionuclude concentration between trees planted over the trench and those planted on the control plot because of the limited root intrusion into the trench by the seedlings. However, when trees were sample in 1986, 1987, and 1988 and analyzed for {sup 241}Am, {sup 238}Pu, {sup 239}Pu, and {sup 237}Np activity, the average activity of all of these isotopes was significantly higher over the trenches than in the control plot. These measurements indicate that tree roots will extract transuranic isotopes from buried, low-level waste. The amount of radioisotopes moved from the trenches to the surface is small and the level in the trees is low enough that dose from exposure will be small. The long term effects of transport of radioisotopes from the trenches to the surface soil was evaluated by estimating the accumulation in the surface soil. Transuranic activity in selected food crops was calculated using the soil activity and the literature derived concentration factors. In all cases, the activity of the transuranic isotopes in the edible portion of the plants was quite low. The activity in the leaf tissue was much higher than in the seed. However, it should be noted that in only one case was the activity higher than the naturally occurring activity of {sup 40}K in the ...
Date: January 1, 1989
Creator: Murphy, C. E. Jr. & Tuckfield, R. C.
Partner: UNT Libraries Government Documents Department

Internal polarized targets

Description: Internal polarized targets offer a number of advantages over external targets. After a brief review of the basic motivation and principles behind internal polarized targets, the technical aspects of the atomic storage cell will be discussed in particular. Sources of depolarization and the means by which their effects can be ameliorated will be described, especially depolarization by the intense magnetic fields arising from the circulating particle beam. The experience of the Argonne Novosibirsk collaboration with the use of a storage cell in a 2 GeV electron storage ring will be the focus of this technical discussion. 17 refs., 11 figs.
Date: January 1, 1989
Creator: Kinney, E. R.; Coulter, K.; Gilman, R.; Holt, R. J.; Kowalczyk, R. S.; Napolitano, J. et al.
Partner: UNT Libraries Government Documents Department

Bose condensate in superfluid sup 4 He and momentum distributions by deep inelastic scattering

Description: There are several reasons for the high interest in the recent experimental and theoretical progress in understanding deep inelastic neutron scattering from liquid {sup 4}He: it tests the fundamental London hypothesis of a connection between superfluidity and Bose condensation; it provides a quantitative test of ab-initio calculational methods for all systems with strong correlations which are the focus of current quantum many-body research; and it establishes the range of validity of deep inelastic scattering as a method for measuring momentum distributions. In this paper we introduce the concepts of impulse approximation in more detail, we describe recent progress in the theory for final state corrections to the impulse approximation, we present quantitative predictions for neutron scattering experiments, we compare with recent high energy pulsed neutron source experiments on liquid {sup 4}He by P. Sokol and colleagues as well as other attempts to extract the Bose condensate fraction from the neutron scattering data, and we discuss the implications of this progress for future momentum distribution experiments in other systems such as liquid {sup 3}He and quasi-elastic electron nucleus scattering. 42 refs., 23 figs.
Date: January 1, 1989
Creator: Silver, R. N. (Los Alamos National Lab., NM (USA)) & Sokol, P. E. (Pennsylvania State Univ., University Park, PA (USA). Dept. of Physics)
Partner: UNT Libraries Government Documents Department

Bulletin: An authoring and change control tool

Description: The Computer Documentation Group at Los Alamos National Laboratory plays an important role in the monthly change control process by documenting network component changes in a publication called the ICN Change Bulletin. BULLETIN is a menu-driven utility used by programmers and computer documentation writers to create articles for the ICN Change Bulletin, which is published in both hardcopy (printed) and softcopy (electronic) forms. BULLETIN also provides information used by other change control software tools. This paper describes the BULLETIN utility and its evolution from a single-purpose authoring tool to a complex, multipurpose authoring and change control tool. 4 refs., 4 figs.
Date: January 1, 1989
Creator: Sanders, C. E. (Los Alamos National Lab., NM (USA))
Partner: UNT Libraries Government Documents Department

Vacuum ultraviolet electronic properties of liquids

Description: The principal aim of this program has been to study the electronic structure of insulating liquids of biological interest over a broad energy range from 0 to 30 eV. The studies basically consist of measuring the reflectance, transmittance, photoemission and photoionization of dielectric liquids in the vacuum ultraviolet spectral region as a function of angle of incidence and energy. these in turn may be interpreted in terms of the electronic structure of each liquid as it is excited by the passage of a charged particle. Optical data provides indirect evidence that collective effects occur in liquids. Direct observation of their existence is substantiated in studies of the energy distribution of electrons specularly scattered from the liquid surface.
Date: January 1, 1989
Creator: Painter, L. R.
Partner: UNT Libraries Government Documents Department

Searching for existing nuclear data

Description: As an example of finding existing data useful for high energy and heavy ion materials analysis the Nuclear Structure References of Brookhaven National Laboratory's National Nuclear Data Center was searched. The search was limited to incident ions of mass {le} 7 amu (excluding alphas) with energies under 100 MeV, and the target nuclei were limited to mass {le} 30 amu. Ease of use, time necessary for retrieval as well as pertinence was explored. Examples of applicable data found during the search are presented. 8 refs., 1 tab.
Date: January 1, 1989
Creator: Tesmer, J. R. (Los Alamos National Lab., NM (USA)); Cokal, H. & Maggiore, C. J. (National Bureau of Standards, Washington, DC (USA). Center for Materials Science)
Partner: UNT Libraries Government Documents Department