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Angular distributions of very low energy recoil ions (open access)

Angular distributions of very low energy recoil ions

We present the first measurements of the angular distribution of recoil ions near 90/sup 0/ with respect to the incident projectile direction. Beams of 22.5 and 33 MeV chlorine ions (incident charge states q =4,5,8) have been used as ''hammer'' beams incident on Ne atoms. We confirm the long standing assumption that these recoil ions are ejected preferentially at angles near 90/sup 0/ with respect to the primary beam direction and with energies typically less than 5 eV. Recoil ions ejected around 90/sup 0/ have an energy distribution appreciably wider than those ejected at either larger or smaller angles. 9 refs., 6 figs.
Date: January 1, 1986
Creator: Gonzalez Lepera, C. E.; Breinig, M.; Burgdoerfer, J.; DeSerio, R.; Elston, S. B.; Gibbons, J. P. et al.
System: The UNT Digital Library
ANL advanced accelerator test facility. Progress report (open access)

ANL advanced accelerator test facility. Progress report

A facility is presently being constructed which can measure transverse and longitudinal wake fields in structures and media. Initial experiments with cavities and plasma are being directed at systems which could be applied to a high energy linear collider, although other experiments should be possible. The facility will eventually operate as a user facility.
Date: January 1, 1986
Creator: Konecny, R.; MacLachlan, J.; Norem, J.; Ruggiero, A. G.; Schoessow, P. & Simpson, J.
System: The UNT Digital Library
ANL computer controlled target storage system: Status report (open access)

ANL computer controlled target storage system: Status report

Design and operation of an isotopic target storage system is described. Due to the cost and effort associated with nuclear target production, it is necessary to protect them. The storage system described was designed to protect up to 90 hydroscopic and readily oxidizing targets under vacuum of 10/sup -6/ torr. The computer controller maintains system integrity during normal use and emergency situations. (JDH)
Date: January 1, 1986
Creator: Klimczak, G.W.; Nardi, B.G. & Travis, D.J.
System: The UNT Digital Library
The ANL experiment for a wake field accelerator using an rf structure (open access)

The ANL experiment for a wake field accelerator using an rf structure

Experiments are planned at ANL to study a new accelerating concept that has been developed during the last few years named the WAKEATRON. This requires a very special, simple configuration of the beams and of the rf structure involved. The basic concepts are explained. Like most proposed experimental work, this too was initiated by a considerable amount of computational work, both analytical and numerical, on which we would like to report. We will then describe details of the planned experiments we will carry out at ANL to check some of our predictions for this concept. These experiments concentrate on beam and cavity geometry applicable to the Wakeatron.
Date: August 27, 1986
Creator: Ruggiero, A. G.; Schoessow, P. & Simpson, J.
System: The UNT Digital Library
ANL High-Resolution Injector (open access)

ANL High-Resolution Injector

The ANL (Argonne National Laboratory) high-resolution injector has been installed to obtain higher mass resolution and higher preacceleration, and to utilize effectively the full mass range of ATLAS (Argonne tandem linac accelerator system). Preliminary results of the first beam test are reported briefly. The design and performance, in particular a high-mass-resolution magnet with aberration compensation, are discussed.
Date: May 1, 1986
Creator: Minehara, E.; Kutschera, W.; Hartog, P. D.; Billquist, P. & Liu, Z.
System: The UNT Digital Library
Annealing of cold worked hypostoichiometric Ni/sub 3/Al alloys using positron lifetime spectroscopy (open access)

Annealing of cold worked hypostoichiometric Ni/sub 3/Al alloys using positron lifetime spectroscopy

Hypostoichiometric Ni/sub 3/Al alloys of composition 76.2 Ni:23.8 Al containing impurity levels of boron and hafnium were either cold rolled or pressed. Rolled and pressed samples were deformed by 20% and 10% thickness reductions, respectively. Samples were annealed isochronally at approximately 50/sup 0/C intervals up to 1050/sup 0/C. Two major annealing stages were apparent in all three alloys studied. These could be attributed to vacancy migration to sinks and annealing of dislocations and(or) recrystallization. The onset of vacancy migration occurred at approximately 200/sup 0/C in all three alloys. Annealing of dislocations started at 650/sup 0/C to 700/sup 0/C and was complete at 1000/sup 0/C for alloys which contained boron and or hafnium impurities. In the pure alloy the onset of dislocation annealing occurred at 800/sup 0/C and was incomplete at the highest (1050/sup 0/C) annealing temperatures reached.
Date: December 1, 1986
Creator: Usmar, S.G. & Lynn, K.G.
System: The UNT Digital Library
Anomalous dimensions of multiquark bound states (open access)

Anomalous dimensions of multiquark bound states

The evolution of six-quark color-singlet state distribution amplitudes is formulated as an application of perturbative quantum chromodynamics to nuclear wave functions. We present a general method of solving the evolution equation for multiquark bound states and predict the asymptotic Q/sup 2/ slope for the deuteron charge form factor as a result.
Date: July 1, 1986
Creator: Ji, Cheung-Ryong
System: The UNT Digital Library
Anomalous low field magnetization in fine filament NbTi conductors (open access)

Anomalous low field magnetization in fine filament NbTi conductors

The first cable conductors for SSC were made with NbTi filaments whose diameters were in the 18 to 23 micron range. In an effort to reduce the magnetization effects in accelerator dipoles resulting from these large filaments, second generation conductors are now being manufactured with much smaller filaments. As part of this development a series of NbTi conductors were made with filament diameters ranging from 8.0 to 2.8 ..mu..m and having an average interfilament spacing of approximately 12% of filament diameter. Measurements at 4.3 K show that as the filament spacing decreases below a certain critical value the low field magnetization increases rapidly. This increase is seen to be strong function of interfilament distance, magnetic field and temperature. Details of these measurements and its implication for practical high current SSC wire design are discussed.
Date: October 1, 1986
Creator: Ghosh, A.K.; Sampson, W.B.; Gregory, E. & Kreilick, T.S.
System: The UNT Digital Library
Anti p-nucleus interaction (open access)

Anti p-nucleus interaction

Status and future prospects of antiproton-nucleus scattering experiments are presented. These scattering experiments were conducted at antiproton beam momentums of 300 and 600 MeV/c on target nuclei of /sup 6/Li, /sup 12/C, /sup 16/O, /sup 18/O, /sup 40/Ca, /sup 48/Ca, and /sup 208/Pb. Antiproton-proton reactions investigated antiproton-nucleus bound or resonant states in antiproton reactions with d, /sup 6/Li, /sup 12/C, /sup 63/Cu, and /sup 209/Bi. Inelastic scattering experiments investigated the spin-isospin dependence of the NN interactions. 19 refs., 1 fig., 1 tab. (DWL)
Date: May 1, 1986
Creator: Peng, J.C.
System: The UNT Digital Library
Anti pp searches for quark-gluon plasma at TeV I (open access)

Anti pp searches for quark-gluon plasma at TeV I

Three experiments that have been approved to run at TeV I are discussed from the viewpoint of their capability to search for evidence of the QCD phase transition in proton-antiproton collisions at 1.6 TeV. One of these experiments, E-735, was proposed as a dedicated search for quark-gluon plasma effects with a detector designed to study large total E/sub T/, low P/sub T/ individual particles. The other two, E-741 (CDF) and E-740 (DO), embody general purpose four-pi detectors designed primarily to study the physics of W and Z bosons and other large P/sub T/ phenomena. The detectors and their quark-gluon plasma signals are compared. 8 refs., 6 figs., 4 tabs. (LEW)
Date: June 1986
Creator: Turkot, Frank
System: The UNT Digital Library
Antiferromagnetic spin fluctuations and the heavy fermion system UPt/sub 3/ (open access)

Antiferromagnetic spin fluctuations and the heavy fermion system UPt/sub 3/

We review the results of inelastic polarized and unpolarized magnetic neutron scattering measurements on the heavy fermion superconductor UPt/sub 3/. Below T/sub chi/ = 18K, we find evidence for antiferromagnetic spin fluctuations with a modulation vector along the c-axis of the hexagonal lattice. This contradicts the analogy often made between UPt/sub 3/ and liquid /sup 3/He, and may have important consequences for the pairing mechanism responsible for superconductivity in this system.
Date: January 1, 1986
Creator: Goldman, A. I.; Shirane, G.; Aeppli, G.; Bucher, E. & Hufnagl, J.
System: The UNT Digital Library
Antimatter clusters from hadronizing quark-gluon plasma (open access)

Antimatter clusters from hadronizing quark-gluon plasma

A realistic model is used for the phase transition between the color deconfining quark-gluon plasma phase and the color confining hadronic gas phase of nuclear matter to discuss the question how quarks and antiquarks hadronize in an expanding quark-gluon plasma. Particular attention is given to the problem associated with the latent heat and latent entropy set free in the hadronization process. Assuming a specific space-time scenario for the phase transition, relative abundances are computed for different hadronic particles and resonances produced during hadronization, showing that in particular antinucleons and light antinuclei are enhanced above their equilibrium abundances in a hadron gas of similar density and temperature. This enhancement is interpreted as a possible signature for the existence of a transient quark-gluon plasma phase in relativistic heavy-ion collisions which can complement the widely discussed strangeness signal. However, detailed dynamical studies of the hadronization process are necessary in order to definitevely settle questions about the quantitative yields. 21 refs., 8 figs.
Date: January 1, 1986
Creator: Heinz, U.
System: The UNT Digital Library
Antinucleon physics (open access)

Antinucleon physics

Some of the recent data from LEAR, Brookhaven, and KEK on low and medium energy interactions of antinucleons (anti N) with nucleons (N) are reviewed and interpreted. Emphasis is on elastic and charge exchange scattering, total cross sections, and studies of anti NN annihilation, with particular focus on the emerging evidence for broad resonances and/or bound states of the anti NN system and the selection rules which reveal the quuark-gluon dynamics of the annihilation process. 69 refs., 8 figs.
Date: January 1, 1986
Creator: Dover, C. B.
System: The UNT Digital Library
Antiproton-hydrogen atom rearrangement-annihilation cross section (open access)

Antiproton-hydrogen atom rearrangement-annihilation cross section

For antiproton energies of several eV or less, annihilation in matter occurs through atomic rearrangement processes in which the antiproton becomes bound to a nucleus prior to annihilation. Existing calculations of the antiproton-hydrogen atom rearrangement cross section are semiclassical and employ the Born-Oppenheimer approximation. They also employ various arguments in regard to the behavior of the system when the Born-Oppenheimer approximation breaks down at small antiproton-proton separations. These arguments indicate that rearrangement is essentially irreversible. In the present study, a detailed investigation was made of the antiproton-hydrogen atom system when the Born-Oppenheimer approximation breaks down. The results of this study indicate that the previous arguments were approximately correct, but that there is a significant probability for rearrangement reversing prior to annihilation. This probability is estimated to be about 20%. 8 refs., 4 figs., 2 tabs.
Date: August 22, 1986
Creator: Morgan, D.L. Jr.
System: The UNT Digital Library
Antiproton proton searches for quark-gluon plasma at the Fermilab collider (open access)

Antiproton proton searches for quark-gluon plasma at the Fermilab collider

The Fermilab Tevatron antiproton-proton collider will begin operation late 1986. A brief description of experiments with the capability for detecting the formation of quark-gluon plasma is presented.
Date: September 1, 1986
Creator: Hojvat, C.
System: The UNT Digital Library
Application of a laser-induced breakdown time-of-flight technique in a flow diagnostic in a CO/sub 2/ free-jet expansion (open access)

Application of a laser-induced breakdown time-of-flight technique in a flow diagnostic in a CO/sub 2/ free-jet expansion

A time-of-flight velocity technique utilizing ions formed by the process of laser-induced (1.064 ..mu..m) breakdown has been used to measure axial flow speeds in a CO/sub 2/ free-jet expansion. For the nozzle stagnation pressure and temperature employed (p0 approx. = 200 torr, T0 approx. = 298K), the axial flow speed is on the order of 630 m/s. 5 refs., 3 figs., 1 tab.
Date: January 1, 1986
Creator: Wantuck, P.J. & Hof, D.E.
System: The UNT Digital Library
The application of angular resolved scatter to the documentation of damage to smooth mirrors (open access)

The application of angular resolved scatter to the documentation of damage to smooth mirrors

Mirrors designed to survive exposure to damaging radiation are being irradiated and then measured to determine the mechanisms of failure and to improve the ability of analysis codes to predict an exposure damage threshold. The differences between survival and catastrophic failure are easily recognized and recorded by macro photography. However, the coal of this project is to quantify the onset of mirror degradation utilizing non contact methods that have good measurement sensitivity to small changes in reflectivity (material properties) and light scatter (roughness). A new angular resolved scatterometer is described that has an extended dynamic range and integrated analysis capable of displaying the surface power spectral density (PSD) over large bandwidths of surface spatial frequencies. Graphical displays of the scattered light power before and after exposure to the radiation are compared and integrated over equivalent spatial bandwidths of sensitivity for other instruments to compare calculated RMS roughness values.
Date: October 30, 1986
Creator: Gillespie, C. H.; Edwards, David F. & Stover, John C.
System: The UNT Digital Library
Application of atomic vapor laser isotope separation to the enrichment of mercury (open access)

Application of atomic vapor laser isotope separation to the enrichment of mercury

Workers at GTE/Sylvania have shown that the efficiency of fluorescent lighting may be markedly improved using mercury that has been enriched in the /sup 196/Hg isotope. A 5% improvement in the efficiency of fluorescent lighting in the United States could provide a savings of approx. 1 billion dollars in the corresponding reduction of electrical power consumption. We will discuss the results of recent work done at our laboratory to develop a process for enriching mercury. The discussion will center around the results of spectroscopic measurements of excited state lifetimes, photoionization cross sections and isotope shifts. In addition, we will discuss the mercury separator and supporting laser mesurements of the flow properties of mercury vapor. We will describe the laser system which will provide the photoionization and finally discuss the economic details of producing enriched mercury at a cost that would be attractive to the lighting industry.
Date: September 1, 1986
Creator: Crane, J. K.; Erbert, G. V.; Paisner, J. A.; Chen, H. L.; Chiba, Z.; Beeler, R.G. et al.
System: The UNT Digital Library
Application of atomic vapor laser isotope separation to the enrichment of mercury (open access)

Application of atomic vapor laser isotope separation to the enrichment of mercury

Workers at GTE/Sylvania have shown that the efficiency of fluorescent lighting may be markedly improved using mercury that has been enriched in the /sup 196/Hg isotope. A 5% improvement in the efficiency of fluorescent lighting in the United States could provide a savings of $450 million dollars in the corresponding reduction of electrical power consumption. We discuss the results of recent work done at our laboratory to develop a process for enriching mercury. The discussion centers around the results of spectroscopic measurements of excited-state lifetimes, photoionization cross sections, and isotope shifts.
Date: September 1, 1986
Creator: Crane, J.; Erbert, G.; Paisner, J.; Chen, H.; Chiba, Z.; Beeler, R. et al.
System: The UNT Digital Library
Application of Bar Codes to the Automation of Analytical Sample Data Collection (open access)

Application of Bar Codes to the Automation of Analytical Sample Data Collection

The Health Protection Department at the Savannah River Plant collects 500 urine samples per day for tritium analyses. Prior to automation, all sample information was compiled manually. Bar code technology was chosen for automating this program because it provides a more accurate, efficient, and inexpensive method for data entry. The system has three major functions: sample labeling is accomplished at remote bar code label stations composed of an Intermec 8220 (Intermec Corp.) interfaced to an IBM-PC, data collection is done on a central VAX 11/730 (Digital Equipment Corp.). Bar code readers are used to log-in samples to be analyzed on liquid scintillation counters. The VAX 11/730 processes the data and generates reports, data storage is on the VAX 11/730 and backed up on the plant's central computer. A brief description of several other bar code applications at the Savannah River Plant is also presented.
Date: January 1, 1986
Creator: Jurgensen, H. A.
System: The UNT Digital Library
Application of borehole geophysics to fracture identification and characterization in low porosity limestones and dolostones (open access)

Application of borehole geophysics to fracture identification and characterization in low porosity limestones and dolostones

Geophysical logging was conducted in exploratory core holes drilled for geohydrological investigations at three sites used for waste disposal on the US Department of Energy's Oak Ridge Reservation. Geophysical log response was calibrated to borehole geology using the drill core. Subsequently, the logs were used to identify fractures and fractured zones and to characterize the hydrologic activity of such zones. Results of the study were used to identify zones of ground water movement and to select targets for subsequent piezometer and monitoring well installation. Neutron porosity, long- and short-normal resistivity, and density logs exhibit anomalies only adjacent to pervasively fractured zones and rarely exhibit anomalies adjacent to individual fractures, suggesting that such logs have insufficient resolution to detect individual fractures. Spontaneous potential, single point resistance, acoustic velocity, and acoustic variable density logs, however, typically exhibit anomalies adjacent to both individual fractures and fracture zones. Correlation is excellent between fracture density logs prepared from the examination of drill core and fractures identified by the analysis of a suite of geophysical logs that have differing spatial resolution characteristics. Results of the study demonstrate the importance of (1) calibrating geophysical log response to drill core from a site, and (2) running a comprehensive …
Date: January 1, 1986
Creator: Haase, C. S. & King, H. L.
System: The UNT Digital Library
Application of channeling in bent crystals to charged particle beams (open access)

Application of channeling in bent crystals to charged particle beams

The process of channeling of charged particle beams in bent crystals is described, including the effects of angular acceptance, spatial acceptance, normal dechanneling, bending dechanneling, and surface acceptance. Some bending applications that have been tried and future possibilities are reviewed. 29 refs., 30 figs. (LEW)
Date: March 1, 1986
Creator: Carrigan, R. A., Jr.
System: The UNT Digital Library
Application of diagnostics to determine motor-operated valve operational readiness (open access)

Application of diagnostics to determine motor-operated valve operational readiness

ORNL has been carrying out an aging assessment of motor-operated valves (MOVs) with the primary objective of recommending diagnostic methods for detecting and trending aging. As a result of experimental investigations at ORNL, it was discovered that the motor current during a valve stroke was a very useful diagnostic parameter for detecting and trending many MOV drive train load variations. The motor curent signatures were analyzed at four levels: mean value for a stroke, gross trends during a stroke, transients, and noise frequency spectra. Examples illustrating the use of this technique are presented. The use of motor current signature analysis was also shown to apply to other electric motor driven equipment. Future work includes developing a data base of MOV diagnostics, including criteria for determining the extent of degradation and application of the technique to other LWR motor driven safety equipment.
Date: January 1, 1986
Creator: Eissenberg, D.M.
System: The UNT Digital Library
Application of DYNA3D in large scale crashworthiness calculations (open access)

Application of DYNA3D in large scale crashworthiness calculations

This paper presents an example of an automobile crashworthiness calculation. Based on our experiences with the example calculation, we make recommendations to those interested in performing crashworthiness calculations. The example presented in this paper was supplied by Suzuki Motor Co., Ltd., and provided a significant shakedown for the new large deformation shell capability of the DYNA3D code. 15 refs., 3 figs.
Date: January 1, 1986
Creator: Benson, D.J.; Hallquist, J.O.; Igarashi, M.; Shimomaki, K. & Mizuno, M.
System: The UNT Digital Library