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Detectors for high resolution dynamic pet

Description: This report reviews the motivation for high spatial resolution in dynamic positron emission tomography of the head and the technical problems in realizing this objective. We present recent progress in using small silicon photodiodes to measure the energy deposited by 511 keV photons in small BGO crystals with an energy resolution of 9.4% full-width at half-maximum. In conjunction with a suitable phototube coupled to a group of crystals, the photodiode signal to noise ratio is sufficient for the… more
Date: May 1, 1983
Creator: Derenzo, S.E.; Budinger, T.F. & Huesman, R.H.
Partner: UNT Libraries Government Documents Department
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Conceptual design summary for modifying Doublet III to a large dee-shaped configuration

Description: The Doublet III tokamak is to be reconfigured by replacing its indented (doublet) vacuum vessel with a larger one of a dee-shaped cross section. This change will permit significantly larger elongated plasmas than is presently possible and will allow higher plasma current (up to 5 MA) and anticipated longer confinement time. Reactor relevant values of stable beta and plasma pressure are predicted. This modification, while resulting in a significant change in capability, utilizes most of the exis… more
Date: May 1, 1983
Creator: Davis, L. G.; Gallix, R.; Luxon, J. L.; Mahdavi, M. A.; Puhn, F. A.; Rock, P. J. et al.
Partner: UNT Libraries Government Documents Department
open access

NOVANET: communications network for a control system

Description: NOVANET is a control system oriented fiber optic local area network that was designed to meet the unique and often conflicting requirements of the Nova laser control system which will begin operation in 1984. The computers and data acquisition devices that form the distributed control system for a large laser fusion research facility need reliable, high speed communications. Both control/status messages and experimental data must be handled. A subset of NOVANET is currently operating on the two… more
Date: May 23, 1983
Creator: Hill, J.R.; Severyn, J.R. & VanArsdall, P.J.
Partner: UNT Libraries Government Documents Department
open access

Addendum to material selection guidelines for geothermal energy-utilization systems. Part I. Extension of the field experience data base. Part II. Proceedings of the geothermal engineering and materials (GEM) program conference (San Diego, CA, 6-8 October 1982)

Description: The extension of the field experience data base includes the following: key corrosive species, updated field experiences, corrosion of secondary loop components or geothermal binary power plants, and suitability of conventional water-source heat pump evaporator materials for geothermal heat pump service. Twenty-four conference papers are included. Three were abstracted previously for EDB. Separate abstracts were prepared for twenty-one. (MHR)
Date: May 1, 1983
Creator: Smith, C. S. & Ellis, P. F., II
Partner: UNT Libraries Government Documents Department
open access

Ultra-relativistic heavy ions and cosmic rays

Description: The collisions of ultra-relativistic heavy ions, E/sub /N/ greater than or equal to 1 TeV/nucleon are most interesting, since, at these energies, matter is produced at sufficiently high energy density that a quark-gluon plasma has a good chance to form. Very heavy ions are also most interesting since the matter forms in a larger volume than for light ions, and the matter is at a somewhat higher energy density. At very high energies with very heavy ions there is great flexibility in the experime… more
Date: May 1, 1983
Creator: McLerran, L.
Partner: UNT Libraries Government Documents Department
open access

NATURAL CONVECTIONIN SHALLOW ENCLOSURES WITH DIFFERENTIALLY HEATED END WALLS AND NONADIABATIC HORIZONTAL WALLS

Description: Numerical studies of laminar natural convection at high Ra numbers in shallow enclosures are reported. In these studies the working fluid is allowed to interact with the horizontal walls. It is shown that even a small amount of heat loss from these walls can lead to a flow structure qualitatively different from the more commonly studied situation where the horizontal walls are adiabatic. This is particularly important in applications where the mass transfer and flow structure are of interest. T… more
Date: May 1, 1983
Creator: Gadgil, A. & Shiralkar, G.
Partner: UNT Libraries Government Documents Department
open access

Diffraction: What Do We Know; What Can We Learn

Description: High energy diffractive scattering is reviewed. We first summarize experimental results and information gleaned from geometric and optical models. We then discuss dynamics from the perspectives of hadron structure and Pomeron structure. Particular emphasis is placed on investigating hadron structure using a simple model of the Pomeron. 58 references.
Date: May 1, 1983
Creator: Randa, J.
Partner: UNT Libraries Government Documents Department
open access

Radiation-effects limits on copper in superconducting magnets

Description: The determination of the response of copper stabilizers to neutron irradiation in fusion-reactor superconducting magnets requires information in four areas: (1) neutron flux and spectrum determination, (2) resistivity changes at zero field, (3) resistivity changes at field, and (4) the cyclic irradiation and annealing. Applications of our current understanding of the limits of copper stabilizers in fusion-reactor designs are explored in two examples. Recommendations for future additions to the … more
Date: May 25, 1983
Creator: Guinan, M.W.
Partner: UNT Libraries Government Documents Department
open access

Consistent linearization method for finite-element analysis of viscoelastic materials

Description: A method of formulating material models for viscoelastic analysis using the finite-element method is presented. The method, named consistent linearization, includes the influence of creep in the material stiffness in a theoretically ideal manner. This method has been applied to the linear viscoelastic analysis of graphite subject to irradiation. Previously, using the initial strain method, short time steps had been required to avoid a numerical instability associated with the rapid transient cr… more
Date: May 1, 1983
Creator: Smith, P.D. & Pelessone, D.
Partner: UNT Libraries Government Documents Department
open access

Applications of simultaneous ion backscattering and ion-induced x-ray emission

Description: Simultaneous ion backscattering and ion-induced x-ray emission (E/sub x/greater than or equal to 300 eV) analyses have been performed using helium ions as probes of the first few hundred nanometers of various materials. These studies serve as a demonstration of the complementary nature of the two types of information obtained. Uncertainties associated with each of the individual techniques were reduced by performing both analyses. The principal advantages of simultaneous analyses over sequentia… more
Date: May 1, 1983
Creator: Musket, R.G.
Partner: UNT Libraries Government Documents Department
open access

Damping beam displacements through phase mixing: an illustrative model

Description: We develop a simple model of a beam transported in a hard wall channel (an idealized very-high-order magnetic-multipole channel). The extremely anharmonic nature of the potential leads to damping of coherent transverse displacements of the beam via phase mixing. For the case of small uniform displacements of the beam we can write down by inspection the analytical form of the motion of the beam centroid. The same technique allows us to evaluate the effects of focussing and scattering elements in… more
Date: May 27, 1983
Creator: Barletta, W. A. & Briggs, R. J.
Partner: UNT Libraries Government Documents Department
open access

Pulse power for the RAPIER B Amplifier KrF laser system

Description: The RAPIER B Amplifier electron beam system has been completed and produces 36kJ of 450 keV electrons in a 150 ns pulse to be used for pumping a KrF laser amplifier. The operating characteristics of the system have been studied. The efficiency of conversion of energy stored in the Marx generator to electron beam output is 72 +- 3% including an 89% designed transfer efficiency. The system is triggered electrically with a 150 ns delay from the command trigger to machine output. The rms jitter for… more
Date: May 25, 1983
Creator: Schlitt, L. G.
Partner: UNT Libraries Government Documents Department
open access

BNL AGS - a context for kaon factories

Description: Figure 1 shows the Brookhaven site with the AGS-CBA complex highlighted. In this photograph the AGS is dwarfed by CBA and indeed during the past few years future plans for particle physics at BNL have been dominated by this enormous project. However, very recently interest in future physics use of the AGS has undergone a strong revival. Indeed, since the beginning of this year, two projects for augmenting the AGS have been proposed. Such projects could keep the AGS viable as a research machine … more
Date: May 1, 1983
Creator: Littenberg, L. S.
Partner: UNT Libraries Government Documents Department
open access

Intense positron beams: linacs - preworkshop copy

Description: Beams of monoenergetic positrons with energies of a few eV to many keV have been used in experiments in atomic physics, solid-state physics and materials science. The production of positron beams from a new source, an electron linac, is described. Intense, pulsed beams of low-energy positrons have been produced by a high-energy beam from an electron linac. The production efficiency, moderator geometry, beam spot size and other positron beam parameters have been determined for electrons with ene… more
Date: May 1, 1983
Creator: Howell, R. H.; Alvarez, R. A.; Woodle, K. A.; Dhawan, S.; Egan, P. O.; Hughes, V. W. et al.
Partner: UNT Libraries Government Documents Department
open access

e+e- collisions in the multi-TeV region

Description: A leading role in the elucidation of the Standard Model during the last few years has been played by e+e- colliding beam experiments. The e+e- discoveries have been made possible by the cleanliness of the experimental conditions and the ability to tune the centre-of-mass energy with precision to the desired value, thus avoiding less interesting background events. We expect history to repeat itself in the next step of elucidating physics beyond the Standard Model. Just as past e+e- machines such… more
Date: May 1, 1983
Creator: Ellis, J.
Partner: UNT Libraries Government Documents Department
open access

Aspects of data on the breakup of highly excited nuclei

Description: There is an awakening of theoretical interest in the mechanisms by which nuclear fragments (4 less than or equal to A less than or equal to 150) are produced in violent collisions of heavy ions. With this in mind we review some aspects of the available experimental data and point out some challenging features against which to test the models. The concept of evaporation is tremendously powerful when applied to pieces of nuclei of low excitation (1 or 2 MeV/u). Current interest focuses on higher … more
Date: May 1, 1983
Creator: Warwick, A. I.; Wieman, H. H.; Gutbrod, H. H.; Ritter, H. G.; Stelzer, H.; Weik, F. et al.
Partner: UNT Libraries Government Documents Department
open access

Physics with polarized beams in e+e/sup -/ colliders

Description: The spin structure of the standard model of electroweak interactions is described, with emphasis on the relevance to polarized beam phenomena. The polarization dependence of the cross section, charge asymmetries, and examples of experimental measurements using longitudinal polarization are given. Longitudinal beam polarization is discussed in some detail, including electroweak radiative corrections. Applications to testing the standard model and looking beyond for additional gauge bosons are co… more
Date: May 1, 1983
Creator: Prescott, Charles Y.
Partner: UNT Libraries Government Documents Department
open access

Critical look at studies of radionuclide migration in fractured granite cores

Description: A series of laboratory experiments studying radionuclide migration were conducted on eleven fractured granite cores from the Climax Stock at the Nevada Test Site. Failor et al (1982) discuss the equipment used, the preparation of the core, the experimental procedure, the data reduction, and the experimental results. They give estimates of the average fracture apertures, retardation values of /sup 85/Sr, /sup 95m/Tc, and /sup 137/Cs relative to /sup 3/H, and the percentage of each radionuclide r… more
Date: May 1, 1983
Creator: Isherwood, D. & Failor, R.
Partner: UNT Libraries Government Documents Department
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Hydrogen sulfide, trace element and sulfur hexafluoride tracer treatment from the Geysers-Calistoga Geothermal Resource Area based on aircraft and surface sampling

Description: This four-day study has provided initial data regarding the short-range transport of pollutants from The Geysers geothermal operations. The initial analysis of the data has shown that a measureable plume of gaseous sulfur (H{sub 2}S) is emitted from the Geysers and transported by surface and upper-level winds to distances beyond 20 km. Only one day had concentrations above 30 ppB and on this day H{sub 2}S was detected as a distinct odor at 1500 m (m.s.1.) at 4 km or more from the Geysers. The i… more
Date: May 1, 1983
Creator: Orgill, M. M.; Lee, R. N.; Nickola, P. W. & Schreck, R. C.
Partner: UNT Libraries Government Documents Department
open access

New heavy-ion-fusion accelerator research program

Description: This paper will briefly summarize the concepts of Heavy Ion Fusion (HIF), especially those aspects that are important to its potential for generating electrical power. It will also note highlights of the various HIF programs throughout the world. Especially significant is that the US Department of Energy (DOE) plans a program, beginning in 1984, aimed at determining the feasibility of using heavy ion accelerators as drivers for Inertial Confinement Fusion (ICF). The new program concentrates on … more
Date: May 1, 1983
Creator: Herrmannsfeldt, W.B.
Partner: UNT Libraries Government Documents Department
open access

Application of alpha spectrometry to the discovery of new elements by heavy-ion-beam bombardment

Description: Starting with polonium in 1898, ..cap alpha..-spectrometry has played a decisive role in the discovery of new, heavy elements. For even-even nuclei, ..cap alpha..-spectra have proved simple to interpret and exhibit systematic trends that allow extrapolation to unknown isotopes. The early discovery of the natural ..cap alpha..-decay series led to the very powerful method of genetically linking the decay of new elements to the well-established ..cap alpha..-emission of daughter and granddaughter … more
Date: May 1, 1983
Creator: Nitschke, J.M.
Partner: UNT Libraries Government Documents Department
open access

Assessment of the performance potential of the martensitic alloy HT-9 for liquid-metal fast-breeder-reactor applications

Description: Martensitic stainless steels appear to provide attractive alternatives to austenitic stainless steels for liquid metal fast breeder reactors (LMFBR). The United States National Cladding/Duct (NCD) Materials Development Program has selected Sandvik alloy HT-9 (12CrMoW) as one of six prime candidate alloys for advanced in-core structural materials having very high peak burnup capabilities. The NCD program, since 1974, has been accumulating engineering data for HT-9. Properties include swelling, i… more
Date: May 1, 1983
Creator: Straalsund, J. L. & Gelles, D. S.
Partner: UNT Libraries Government Documents Department
open access

Design of a high-temperature first wall/blanket for a d-d compact Reversed-Field-Pinch reactor (CRFPR)

Description: A high-temperature first wall/blanket which would take full advantage of the absence of tritium breeding in a d-d reactor was designed. This design which produces steam at p = 7 MPa and T = 538/sup 0/C at the blanket exit eliminates the requirement for a separate steam generator. A steam cycle with steam-to-steam reheat yielding about 37.5 percent efficiency is compatible with this design.
Date: May 1, 1983
Creator: Dabiri, A. E. & Glancy, J. E.
Partner: UNT Libraries Government Documents Department
open access

4. pi. data of relativistic nuclear collisions. [Plastic ball]

Description: During the past two years, complete events of relativistic nuclear collisions are being studied with the Plastic Ball, the first electronic nonmagnetic particle-identifying 4..pi.. spectrometer. It is well suited to handle the large multiplicities in these reactions and allows collection of data at a rate sufficient to make further software selections to look at rare events. The analysis of the data follows various lines covering topics like thermalization, stopping or transparency, cluster-pro… more
Date: May 1, 1983
Creator: Gutbrod, H.H.; Gustafsson, H.A. & Kolb, B.
Partner: UNT Libraries Government Documents Department
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