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Measurements of the dependence of damage thresholds on laser wavelength, pulse duration and film thickness

Description: Results of three experiments will be described. We used 351-nm and 355-nm pulses with durations of 0.6, 1, 5 and 9 ns measure thresholds for a variety of anti-reflectance and high reflectance coatings. The functional form t/sup m/, with t the pulse duration, was used to scale fluence thresholds measured at 0.6 ns to those measured at 9.0 ns. Values of the coefficient m ranged from 0.10 to 0.51. The average value was 0.30. In the second experiment, we measured thresholds at 1064 nm, 527 nm and 3… more
Date: March 1, 1984
Creator: Rainer, F.; Vercimak, C.L.; Milam, D.; Carniglia, C.K. & Tuttle Hart, T.
Partner: UNT Libraries Government Documents Department
open access

Nuclear mass formula with a neutron skin degree of freedom and finite-range model for the surface energy

Description: We study the possibility of extending the model used by Moeller and Nix in 1980 to calculate nuclear masses and fission barriers for nuclei throughout the periodic system, to describe compressibility effects and the existence of a neutron skin. 9 references. (WHK)
Date: March 1, 1984
Creator: Moeller, P. & Myers, W.D.
Partner: UNT Libraries Government Documents Department
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Recent results of studies of acceleration of compact toroids

Description: The observed gross stability and self-contained structure of compact toroids (CT's) give rise to the possibility, unique among magnetically confined plasmas, of translating CT's from their point of origin over distances many times their own length. This feature has led us to consider magnetic acceleration of CT's to directed kinetic energies much greater than their stored magnetic and thermal energies. A CT accelerator falls in the very broad gap between traditional particle accelerators at one… more
Date: March 2, 1984
Creator: Hammer, J. H.; Hartman, C. W. & Eddleman, J.
Partner: UNT Libraries Government Documents Department
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Novel, convenient, and nonpersistent radiotracer for environmental and energy applications

Description: A newly-available radioisotopic system, /sup 172/Hf-/sup 172/Lu, has excellent potential for tracer applications in which nuclear data acquisition must be accomplished in real time. The 6.7-day half-life of /sup 172/Lu is sufficient for a large fraction of tracer experiments, and should allow the direct incorporation of /sup 172/Lu into tests that have traditionally utilized much longer-lived radionuclides. Since /sup 172/Lu is the daughter component of a radioisotope generator, however, its ef… more
Date: March 12, 1984
Creator: Grant, P.M.
Partner: UNT Libraries Government Documents Department
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Large area spark counter with fine time and position resolution

Description: The key properties of spark counters include their capability of precision timing (at the sub 100 ps level) and of measuring the position of the charged particle to high accuracy. At SLAC we have undertaken a program to develop these devices for use in high energy physics experiments involving large detectors. A spark counter of size 1.2 m x 0.1 m has been constructed and has been operating continuously in our test setup for several months. Some details of its construction and its properties as… more
Date: March 1, 1984
Creator: Ogawa, A.; Fujiwara, N.; Pestov, Yu.N. & Sugahara, R.
Partner: UNT Libraries Government Documents Department
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ECRH and ICRH in the TMX-U Tandem Mirror

Description: In the Tandem Mirror Experiment Upgrade (TMX-U), the formation of a thermal barrier and the potential plugging of ion end loss were achieved at central-cell densities up to 2 x 10/sup 12/ cm/sup -3/. The presence of a thermal barrier was confirmed by direct measurement, and ion axial-confinement times in the range 50 to 100 ms were measured. The ECRH in the end cells (a) initiates plasma startup, (b) generates hot, mirror-confined electrons to form thermal barriers, and (c) creates the plugging… more
Date: March 15, 1984
Creator: Stallard, B. W.; Cummins, W. F.; Molvik, A. W.; Poulsen, P.; Simonen, T. C.; Falabella, S. et al.
Partner: UNT Libraries Government Documents Department
open access

Calibration of a neutron log in partially saturated media IV: effects of sonde-wall gap

Description: A gap between a neutron sonde and the wall of a borehole can have a significant effect on the observed count rate. This effect was determined experimentally to be linear with gaps as large as 2.5 cm. The count rate is given by N/sub N/ = K/sub 0/ + K/sub 1/g where K/sub 0/ is the count rate that would be observed at zero gap, and g is the gap. The parameters K/sub 0/ and K/sub 1/ are dependent on both water (ie. hydrogen) content and bulk density. In many situations failure to correct the count… more
Date: March 8, 1984
Creator: Axelrod, M. C. & Hearst, J. R.
Partner: UNT Libraries Government Documents Department
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Physical protection system using activated barriers

Description: The Argonne National Laboratory has recently installed an activated barrier, the Access Denial System, to upgrade its security. The technology of this system was developed in the late 70's by Sandia National Laboratory-Albuquerque. The Argonne National Laboratory is the first Department of Energy facility to use this device. Recent advancements in electronic components provide the total system support that makes the use of an activated barrier viable and desirable. The premise of an activated b… more
Date: March 1, 1984
Creator: Timm, R. E.; Zinneman, T. E.; Haumann, J. R.; Flaugher, H. A. & Reigle, D. L.
Partner: UNT Libraries Government Documents Department
open access

Performance of a large-scale melter off-gas system utilizing simulated SRP DWPF waste

Description: The Department of Energy and the DuPont Company have begun construction of a Defense Waste Processing Facility to immobilize radioactive waste now stored as liquids at the Department of Energy's Savannah River Plant. The immobilization process solidifies waste sludge by vitrification into a leach-resistant borosilicate glass. Development of the process has been the responsibility of the Savannah River Laboratory. As part of the development, two large-scale glass melter systems have been de… more
Date: March 1, 1984
Creator: Kessler, J L & Randall, C T
Partner: UNT Libraries Government Documents Department
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Sensitive dependence to parameters, fat fractals, and universal strange attractors

Description: There are many nonlinear differential equations for which two different types of behavior, such as chaos and periodicity, are interwoven in a complex and intricate manner, so that the bifurcation parameters form a ''fat fractal''. The result is that statistical averages vary wildly with parameters and, strictly speaking, prediction becomes impossible even in the statistical sense. (For example, climate, as well as weather, is unpredictable.) There is, however, order in this unpredictable behavi… more
Date: March 1, 1984
Creator: Farmer, J.D.
Partner: UNT Libraries Government Documents Department
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Workshop on borehole measurements and interpretation in scientific drilling - identification of problems and proposals for their solution: proceedings

Description: Critical instrumentation needs for borehole-oriented, geoscience research were identified in a program consisting of formal presentations, psoter sessions and a workshop. The proceedings include results of the workshops, abstracts of the papers and poster sessions, and the attendance list. Details of any of the presentations should be obtained from the individual authors. Separate entries were prepared for individual presentations.
Date: March 1, 1984
Creator: Cooper, D. L. & Traeger, R. K.
Partner: UNT Libraries Government Documents Department
open access

High-spin gamma-ray spectroscopy

Description: Nuclei can carry angular momentum by single-particle alignments and by collective motion, as has been well illustrated in discrete-line spectroscopy. From continuum ..gamma..-ray studies in still higher spin regions, it appears that these modes both continue. In favorable cases in rare-earth nuclei, particle alignments from the valence shell separate from proton alignments from the next higher shell. A new generation of Compton-suppressed Ge detector arrays will greatly enhance high-spin studie… more
Date: March 1, 1984
Creator: Diamond, R. M.
Partner: UNT Libraries Government Documents Department
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Low level signal data acquisition for the MFTF-B superconducting magnet system

Description: Acquisition of low level signals from sensors mounted on the superconducting magnets in the Tandem Mirror Fusion Test Facility (MFTF-B) impose very strict requirements on the magnet signal conditioning and data acquisition system. Of the various types of sensors required, thermocouples and strain gages produce very low level outputs. These low level outputs must be accurately measured in the harsh environment of slowly varying magnetic fields, cryogenic temperatures, high vacuum, 80 kV pulse po… more
Date: March 28, 1984
Creator: Montoya, C.R.
Partner: UNT Libraries Government Documents Department
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Evaluation of the radiation resistance of high-density polyethylene. [Gamma Rays]

Description: Mechanical tests following gamma irradiation and creep tests during irradiation have been conducted on high-density polyethylene (HDPE) to provide data to help assess the adequacy of this material for use in high integrity containers (HICs). Two types of HDPE, a highly cross-linked rotationally molded material and a non-cross-linked blow molded material, were used in these tests. Gamma-ray irradiations were performed at several dose rates in environments of air, Barnwell and Hanford backfill so… more
Date: March 1, 1984
Creator: Dougherty, D. R.; Adams, J. W. & Barletta, R. R.
Partner: UNT Libraries Government Documents Department
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Coherent vuv and soft x-ray radiation from undulators in modern storage rings

Description: Magnetic structures in modern storage rings provide an assured route to fundamentally new opportunities for extending coherent radiation experiments to the vacuum ultraviolet and soft x-ray spectral regions. Coherent power levels of order 10 milliwatts are anticipated, in a fully spatially coherent beam, with a longitudinal coherence length of order 1 ..mu..m. In addition to broad tuneability and polarization control, the radiation would occur in 20 psec pulses, at 500 MHz repetition rate.
Date: March 1, 1984
Creator: Kim, K. J.; Halbach, K. & Attwood, D.
Partner: UNT Libraries Government Documents Department
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ICRF Heating in the Tandem Mirror Experiment-Upgrade (TMX-U)

Description: Central cell plasma in Tandem Mirror Experiment-Upgrade (TMX-U) are heated with 100 kW of ICRF transmitter power to ion temperatures of 1.5 keV at densities of 2 x 10/sup 12/ cm/sup -3/. We have used two Faraday-shielded antennas: the first had one 90/sup 0/ loop; and the second, in current use, has two 170/sup 0/ loops connected in an m = 1 configuration. We are also installing a slot antenna. Optimum heating for wave launching occus below the cyclotron frequency, consistent with slow wave hea… more
Date: March 1, 1984
Creator: Molvik, A. W.; Cummins, W. F.; Falabella, S.; Poulsen, P.; Barter, J.; Dimonte, G. et al.
Partner: UNT Libraries Government Documents Department
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Analysis of complex vessel experiments using the Hybrid Lagrangian-Eulerian containment code ALICE-II

Description: This paper describes the ALICE-II analysis of and comparison with complex vessel experiments. Tests SM-2 through SM-5 were performed by SRI International in 1978 in studying the structural response of 1/20 scale models of the Clinch River Breeder Reactor to a simulated hypothetical core-disruptive accident. These experiments provided quality data for validating treatments of the nonlinear fluid-structure interactions and many complex excursion phenomena, such as flow through perforated structur… more
Date: March 1, 1984
Creator: Wang, C. Y.; Ku, J. L. & Zeuch, W. R.
Partner: UNT Libraries Government Documents Department
open access

Perspective on demonstrations of compliance for high-level waste disposal

Description: This paper discusses a perspective which we have developed on the problem of demonstrating compliance of high-level waste repositories with system performance standards. Our viewpoint arises from two primary concerns - first, that the US Environmental Protection Agency's proposed environmental standard for high-level waste disposal appears to require demonstrations of compliance which are incompatible with scientific knowledge, and, second, that the federal agencies involved in the licensing pr… more
Date: March 15, 1984
Creator: Kocher, D. C.; Smith, E. D.; O'Kelly, G. D. & Sjoreen, A. L.
Partner: UNT Libraries Government Documents Department
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Search for neutral, penetrating, metastable particles produced in the SLAC beam dump

Description: A search was made for neutral objects which might be produced by 20 GeV electrons incident on the SLAC beam dump, penetrate the downstream natural shielding, and decay upstream of an electromagnetic shower calorimeter. With about 30 coulombs of electrons dumped, no candidate events were found above an energy of approx. 2 GeV. Preliminary analysis implies the 95% confidence level limit on the product of mass and lifetime of light axion-like bosons decaying primarily into two photons to be greate… more
Date: March 1, 1984
Creator: Bjorken, J.
Partner: UNT Libraries Government Documents Department
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Nova laser alignment control system

Description: Alignment of the Nova laser requires control of hundreds of optical components in the ten beam paths. Extensive application of computer technology makes daily alignment practical. The control system is designed in a manner which provides both centralized and local manual operator controls integrated with automatic closed loop alignment. Menudriven operator consoles using high resolution color graphics displays overlaid with transport touch panels allow laser personnel to interact efficiently wi… more
Date: March 29, 1984
Creator: Van Arsdall, P.J.; Holloway, F.W.; McGuigan, D.L. & Shelton, R.T.
Partner: UNT Libraries Government Documents Department
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Beam experiment programs in the USA

Description: It has been demonstrated that an intense beam with the space charge defocussing force as large as the average focussing forces of the channel can be transported over many lattice periods without losing either the current or the optical quality. This conclusion, which is consistent with the PIC code results, has an important implication in designing a linear induction accelerator driver for inertial confinement fusion.
Date: March 1, 1984
Creator: Kim, C.
Partner: UNT Libraries Government Documents Department
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Soft x-ray laser experiments at Novette Laser Facility

Description: We discuss the results of and future plans for experiments to study the possibility of producing an x-ray laser. The schemes we have investigated are all pumped by the Novette Laser, operated at short pulse (tau/sub L/ approx. 100 psec) and an incident wavelength of lambda /sub L/ approx. 0.53 ..mu..m. We have studied the possibility of lasing at 53.6, 68.0 to 72.0, 119.0, and 153.0 eV, using the inversion methods of resonant photo-excitation, collisional excitation, and three-body recombinatio… more
Date: March 5, 1984
Creator: Matthews, D.; Hagelstein, P.; Rosen, M.; Kauffman, R.; Lee, R.; Wang, C. et al.
Partner: UNT Libraries Government Documents Department
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Finite element method for solving neutron transport problems

Description: A finite element method is introduced for solving the neutron transport equations. Our method falls into the category of Petrov-Galerkin solution, since the trial space differs from the test space. The close relationship between this method and the discrete ordinate method is discussed, and the methods are compared for simple test problems.
Date: March 21, 1984
Creator: Ferguson, J.M. & Greenbaum, A.
Partner: UNT Libraries Government Documents Department
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X-ray microprobe characterization of materials: the case for undulators on advanced storage rings

Description: The unique properties of X rays offer many advantages over electrons and other charged particles for the microcharacterization of materials. X rays are more efficient in exciting characteristic X-ray fluorescence and produce higher fluorescent signals to backgrounds than obtained with electrons. Detectable limits for X rays are a few parts per billion and are 10/sup -3/ to 10/sup -5/ less than for electrons. Energy deposition in the sample by X rays is 10/sup -3/ to 10/sup -4/ less than for ele… more
Date: March 17, 1984
Creator: Sparks, C.J. Jr.
Partner: UNT Libraries Government Documents Department
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