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The Emittances and Brightnesses of High-Intensity Negative Ion Sources

Description: The emittances of high-intensity ion beams extracted from cesium sputter negative ion sources equipped with cylindrical and ellipsoidal solid tungsten and spiral-wound tantalum (General Ionex Corporation, Model 860), and cesium surface ionizers have been measured for several ion species, including /sup 12/C/sup -/, /sup 28/Si/sup -/, /sup 58/Ni/sup -/, and /sup 197/Au/sup -/. While certain sets of data from the ellipsoidal and cylindrical geometry ionizer sources suggest a moderate growth in em… more
Date: January 1, 1987
Creator: Alton, G. D. & McConnell, J. W.
Partner: UNT Libraries Government Documents Department
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History of Proton Linear Accelerators

Description: Some personal recollections are presented that relate to the author's experience developing linear accelerators, particularly for protons. (LEW)
Date: January 1, 1987
Creator: Alvarez, L.W.
Partner: UNT Libraries Government Documents Department
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High-precision hyperfine structure measurement in slow atomic ion beams by collinear laser-rf double resonance

Description: A new collinear laser-ion beam apparatus for slow ions (1 to 1.5 keV) has been built for measuring the hyperfine structure of metastable levels of ions with laser-rf double resonance technique. Narrow linewidths of approx.60 kHz (FWHM) have been observed for the first time in such systems. As a first application the hyperfine structure of the 4f/sup 7/(/sup 8/S/sup 0/)5d /sup 9/D/sub J//sup 0/ metastable levels of /sup 151,153/Eu/sup +/ has been measured with high precision. 10 refs., 8 figs.
Date: January 1, 1987
Creator: Amarjit Sen, Childs, W.J. & Goodman, L. S.
Partner: UNT Libraries Government Documents Department
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Linear Water Influx of an Infinite Aquifer Through a Partially Communicating Fault

Description: This paper presents a linear flow water influx analysis method where the aquifer is separated from the reservoir by a partially communicating fault. Transient pressure distributions are considered both in the reservoir and in the aquifer. Cases where the leaky fault is located within the aquifer can be analyzed with this model given a superposition of constant rate flow periods at the oil-water interface. Constant production rate is specified at the inner boundary, without inner boundary storag… more
Date: January 20, 1987
Creator: Ambastha, Anil K. & Sageev, Abraham
Partner: UNT Libraries Government Documents Department
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Angular resolution in underground detectors and a status report of the Soudan II nucleon decay detector

Description: This paper is a status report of the Soudan II honeycomb drift chamber project. It reports on the physics goals, present progress and future schedule of our experiment. It also includes a discussion of the angular resolution of cosmic ray muons which can be achieved in underground detectors, and in particular how to calibrate the resolution using the moon's shadow in cosmic rays. This last point has relevance in trying to understand the angular distributions in the reported observations of unde… more
Date: January 1, 1987
Creator: Ambats, I.; Ayres, D.; Barrett, W.; Barron, K.; Dawson, J.; Fields, T. et al.
Partner: UNT Libraries Government Documents Department
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Performance of the Soudan II honeycomb drift chambers

Description: The Soudan II nucleon decay project is in the process of building 260 identical 5-ton fine grained calorimeter modules for the study of nucleon decay and cosmic ray physics in the Soudan Iron Mine in Minnesota. Several of these modules have been studied on a cosmic ray test stand on the surface at Argonne National Lab. Several have been installed on location in the mine, 700 m under the surface (2200 mwe overburden). In addition, many studies of trigger efficiency, pattern recognition and backg… more
Date: January 1, 1987
Creator: Ambats, I.; Ayres, D.; Barrett, W.; Dawson, J.; Fields, T.; Goodman, M.C. et al.
Partner: UNT Libraries Government Documents Department
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Initial results from the Soudan II experiment

Description: This paper reports on progress in the construction, installation and operation of the Soudan II nucleon decay detector.
Date: January 1, 1987
Creator: Ambats, I.; Ayres, D.; Courant, H.; DasGupta, U.; Allison, W.; Barr, G. et al.
Partner: UNT Libraries Government Documents Department
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The KIVA-II computer program for transient multidimensional chemically reactive flows with sprays

Description: Since its public release in 1985, the KIVA computer program has been utilized for the time dependent analysis of chemically reacting flows with sprays in two and three space dimensions. This paper describes some of the improvements to the original version that have been made since that time. The new code called KIVA-II is planned for public release in early 1988. KIVA-II improves the earlier version in the accuracy and efficiency of the computational procedure, the accuracy of the physics submo… more
Date: January 1, 1987
Creator: Amsden, A. A.; Butler, T. D. & O'Rourke, P. J.
Partner: UNT Libraries Government Documents Department
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Implementation and optimization of portable standard LISP for the Cray

Description: Portable Standard LISP (PSL), a dialect of LISP developed at the University of Utah, has been implemented on the CRAY-1s and CRAY X-MPs at the Los Alamos National Laboratory and at the National Magnetic Fusion Energy Computer Center at Lawrence Livermore National Laboratory. This implementation was developed using a highly portable model and then tuned for the Cray architecture. The speed of the resulting system is quite impressive, and the environment is very good for symbolic processing. 5 re… more
Date: January 1, 1987
Creator: Anderson, J.W.; Kessler, R.R. & Galway, W.F.
Partner: UNT Libraries Government Documents Department
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Interaction of biological systems with static and ELF electric and magnetic fields

Description: Although background levels of atmospheric electric and geomagnetic field levels are extremely low, over the past several decades, human beings and other life forms on this planet have been subjected to a dramatically changing electromagnetic milieu. An exponential increase in exposure to electromagnetic fields has occurred, largely because of such technological advances as the growth of electrical power generation and transmission systems, the increased use of wireless communications, and the u… more
Date: January 1, 1987
Creator: Anderson, L.E.; Kelman, B.J. & Weigel, R.J. (eds.)
Partner: UNT Libraries Government Documents Department
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Where does CBT (computer-based training) fit in, now that we know so much. A front end analysis study

Description: Computer-based training (CBT) has now been in existence for over two decades. It has been implemented in both the private sector and government organizations at an exponential rate. Nevertheless, many institutions, particularly educational institutions, have not yet introduced CBT. Our knowledge of what works and what does not, as well as hardware and software advances, has greatly increased in the past few years. This paper addresses many management considerations with respect to CBT. First, w… more
Date: January 1, 1987
Creator: Andrews, A. E. & Trainor, M. S.
Partner: UNT Libraries Government Documents Department
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Atmospheric Releases From Severe Nuclear Accidents: Environmental Transport and Pathways to Man: Modelling of Radiation Doses to Man From Chernobyl Releases

Description: The Chernobyl accident released a large amount of highly fractionated radioactive debris, including approximately 89 PBq of /sup 137/Cs. We calculated the resulting collective dose commitment to the Northern Hemisphere via the pathways of external exposure and ingestion of radionuclides withd food. We developed a rural/urban model of external dose and we used the PATHWAY model for ingestion. The results are a collective dose commitment of 630,000 person-Gy over the first year and 1,200,000 pers… more
Date: January 1, 1987
Creator: Anspaugh, L. R.; Goldman, M. & Catlin, R. J.
Partner: UNT Libraries Government Documents Department
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Fundamental noise processes in a laser excited optical filter

Description: A rubidium narrow bandwidth optical filter is being investigated as a device for detecting weak narrow bandwidth radiation. In our configuration, the optical filter is actively pumped (or laser excited, i.e., LEOF). This configuration has a major inherent advantage over a passive optical filter, namely, wavelength versatility. One possible limitation to the Rb LEOF is due to an intrinsic noise source caused by the energy pooling of Rb 5p atoms which are produced by the pump laser. This process,… more
Date: January 1, 1987
Creator: Apel, E. C.; Gosnell, T. R.; Shay, T. M. & Samadani, R.
Partner: UNT Libraries Government Documents Department
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Alteration of National Glass in Radioactive Waste Repository Host Rocks: A Conceptional Review

Description: The storage of high-level radioactive wastes in host rocks containing natural glass has potential chemical advantages, especially if the initial waste temperatures are as high as 250/sup 0/C. However, it is not certain how natural glasses will decompose when exposed to an aqueous phase in a repository environment. The hydration and devitrification of both rhyolitic and natural basaltic natural glasses are reviewed in the context of hypothetical thermodynamic phase relations, infrared spectrosco… more
Date: January 1, 1987
Creator: Apps, J. A.
Partner: UNT Libraries Government Documents Department
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Thermal-hydraulic modeling of porous bed reactors

Description: Optimum design of nuclear reactor core requires an iterative approach between the thermal-hydraulic, neutronic and operational analysis. This paper concentrates on the thermal-hydraulic behavior of a hydrogen cooled, small particle bed reactor (PBR). The PBR core, modeled here, consists of a hexagonal array of fuel elements embedded in a moderator matrix. The fuel elements are annular packed beds of fuel particles held between two porous cylindrical frits. These particles, 500 to 600 ..mu..m in… more
Date: January 1, 1987
Creator: Araj, K. J. & Nourbakhsh, H. P.
Partner: UNT Libraries Government Documents Department
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Ultra-high temperature direct propulsion

Description: Potential advantages of ultra-high exhaust temperature (3000 K - 4000 K) direct propulsion nuclear rockets are explored. Modifications to the Particle Bed Reactor (PBR) to achieve these temperatures are described. Benefits of ultra-high temperature propulsion are discussed for two missions - orbit transfer (..delta..V = 5546 m/s) and interplanetary exploration (..delta..V = 20000 m/s). For such missions ultra-high temperatures appear to be worth the additional complexity. Thrust levels are redu… more
Date: January 1, 1987
Creator: Araj, K. J.; Slovik, G.; Powell, J. R. & Ludewig, H.
Partner: UNT Libraries Government Documents Department
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Plasmon resonance absorption in layered structures of silver with periodic corrugation

Description: Plasmon resonance absorption in periodically corrugated layered structures of silver was studied by the photoacoustic method. The layered structures were self-supporting and corrugated with a period of 1888 nm and amplitude varying from 6 to 12 nm, depending on the thickness. Experimental results of resonance absorption of 633-nm photons were analyzed in terms of the propagation and damping constants of coupled modes of surface plasmons. The coupling efficiency of incident photons to these mode… more
Date: January 1, 1987
Creator: Arakawa, E.T.; Inagaki, T. & Goudonnet, J.P.
Partner: UNT Libraries Government Documents Department
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Point vortex dynamics: Recent results and open problems

Description: The concept of point vortex motion, a classical model in the theory of two-dimensional, incompressible fluid mechanics, was introduced by Helmholtz in 1858. Exploration of the solutions to these equations has made fitful progress since that time as the point vortex model has been brought to bear on various physical situations: atomic structure, large-scale weather patterns, ''vortex street'' wakes, vortex lattices in superfluids and superconductors, etc. The point vortex equations also provide … more
Date: January 1, 1987
Creator: Aref, H.; Kadtke, J. B.; Zawadzki, I.; Campbell, L. J. & Eckhardt, B.
Partner: UNT Libraries Government Documents Department
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Design of a transuranic VUV spectrometer

Description: Most of our present knowledge about the physics of 5f systems derives from studies of uranium and its compounds. This is particularly true in the case of photoemission measurements where the intense radioactivity has prevented studies at synchrotron sources. The development of a transuranic VUV spectrometer capable of safe operation at a synchrotron source would represent a giant step in 5f research. This paper describes the conceptual design of such a spectrometer.
Date: January 1, 1987
Creator: Arko, A. J.
Partner: UNT Libraries Government Documents Department
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Microwave-induced air breakdown in a free air geometry

Description: We report on trial experiments, using an open geometry, to measure the breakdown behavior of short, intense microwave pulses in low pressure air.
Date: January 1, 1987
Creator: Armstrong, William T.; Roussel-Dupre, Robert T.; Karl, Robert; Buchwald, Melvin I. & Graham, Gerry
Partner: UNT Libraries Government Documents Department
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Scientific considerations in the design of the Mars observer gamma-ray spectrometer

Description: Cosmic-ray primary and secondary particles induce characteristic gamma-ray and neutron emissions from condensed bodies in our solar system. These characteristic emissions can be used to obtain qualitative and quantitative elemental analyses of planetary surfaces from orbital altitudes. Remote sensing gamma-ray spectroscopy has been successfully used to obtain elemental composition of the Moon and Mars during United States Apollo 15 and 16 missions and the Soviet Luna and Mars missions. A remote… more
Date: January 1, 1987
Creator: Arnold, J. R.; Boynton, W. V.; Englert, P.; Feldman, W. C.; Metzger, A. E.; Reedy, R. C. et al.
Partner: UNT Libraries Government Documents Department
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Non-resonant field generation

Description: Production of fields for particle acceleration by pulse technology is reviewed. Special attention is focussed on several recently proposed schemes for generation of very high gradients, both in metallic structures and plasmas. Ongoing and planned experimental activities in these areas are discussed. 24 refs., 6 figs., 5 tabs.
Date: January 1, 1987
Creator: Aronson, S.H.
Partner: UNT Libraries Government Documents Department
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Preparation and benchmarking of ANSL-V cross sections for advanced neutron source reactor studies

Description: Validity of selected data from the fine-group neutron library was satisfactorily tested in performance parameter calculations for the BAPL-1, TRX-1, and ZEEP-1 thermal lattice benchmarks. BAPL-2 is an H/sub 2/O moderated, uranium oxide lattice; TRX-1 is an H/sub 2/O moderated, 1.31 weight percent enriched uranium metal lattice; ZEEP-1 is a D/sub 2/O-moderated, natural uranium lattice. 26 refs., 1 tab.
Date: January 1, 1987
Creator: Arwood, J. W.; Ford, W. E., III; Greene, N. M.; Primm, R. T., III; Waddell, M. W.; Webster, C. C. et al.
Partner: UNT Libraries Government Documents Department
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Response of propellant to hypervelocity attack

Description: This study was undertaken to examine the behavior of heterogeneous gun propellants when they are impacted by shaped-charge jets. In the immediate area surrounding the impact point, the pressure is believed to be above the detonation pressure of the full-density propellant. However, a detonation does not necessarily occur, and if it does, the detonation does not necessarily propagate. This is a function of grain size, web, perf pattern, jet diameter, propellant failure diameter, and composition.… more
Date: January 1, 1987
Creator: Asay, B.W.; Ramsay, J.B. & Campbell, A.W.
Partner: UNT Libraries Government Documents Department
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