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Pion correlations as a function of atomic mass in heavy ion collisions

Description: The method of two pion interferometry was used to obtain source-size and lifetime parameters for the pions produced in heavy ion collisions. The systems used were 1.70 {center dot} A GeV {sup 56}Fe + Fe, 1.82 {center dot} A GeV {sup 40}Ar + KCl and 1.54 {center dot} A GeV {sup 93}Nb + Nb, allowing for a search for dependences on the atomic number. Two acceptances (centered, in the lab., at {approximately} 0{degrees} and 45{degrees}) were used for each system, allowing a search for dependences o… more
Date: November 26, 1989
Creator: Chacon, A.D.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Profile modification by the ponderomotive force in spherical targets

Description: Experiments have been performed by LLL which indicate a definite density profile steepening. One possible mechanism for this effect is the ponderomotive force. LASNEX has been modified to include the light momentum deposition in the form rho dv/dt = -nabla P - nabla(radical epsilon + radical 1/epsilon) I/2c. Results will be presented from numerical simulations on spherical glass targets at laser intensities from 10/sup 14/ to 10/sup 16/ watts/cm/sup 2/. Emphasis is placed on the nature of the d… more
Date: October 26, 1977
Creator: Larsen, J. T. & Harte, J.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Development of superconductors for applications in high-field, high-current-density magnets for fusion research

Description: The development of large-bore, high-field magnets for fusion energy applications requires a system approach to both magnet and conductor design. At Lawrence Livermore National Laboratory (LLNL), the criteria used to choose superconductors include: strain tolerance, radiation tolerance, heat removal, stability, fabricability, and cost. We report on the performance of industrially produced, prototype, Ti-modified Nb/sub 3/Sn wires developed with LLNL support. Wire performance characteristics eval… more
Date: September 26, 1986
Creator: Summers, L. T. & Miller, J. R.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Exploding pusher targets for the SHIVA laser system

Description: The first targets for the 20 TW SHIVA laser system were designed. They are simple glass micro-balloons, approximately 300 ..mu..m in diameter and 2 ..mu..m thick, filled with D-T gas. Using LASNEX, whose model physics was utilized successfully for ARGUS targets, we optimize for both gain and yield. The target behaves as an exploding pusher. Different simple analytic models for the physics of this mode are presented, and are tested by comparing their scaling predictions, at constant absorbed pow… more
Date: September 26, 1977
Creator: Rosen, M. D.; Larsen, J. T. & Nuckolls, J. H.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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The q q meson states with J sup PC = 2 sup ++ and 0 sup ++

Description: The lowest mesons made up of a light quark and a strange quark produced from a K beam show a good agreement with expectations of the quark model. This good agreement leads to the prediction of the light isoscalar and isovector states and the isoscalar s{bar s} states. Except for one mystery The X(1590) the 2{sup ++} states seems to be well described by the expected ideally mixed q{bar q} states up to 2. 0 GeV. Above 2.0 GeV a new degree of freedom seems to be excited with respect to the breakdo… more
Date: September 26, 1991
Creator: Longacre, R. S.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Atom-in-jellium models

Description: The author describes in this paper the atom-in-jellium calculations he has been doing over the last ten years. He tries to emphasize reasons for doing this sort of calculations and why he devised a model which is different in some respects from others.
Date: April 26, 1985
Creator: Liberman, D.A.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Fundamental studies of fusion plasmas

Description: The major portion of this program is devoted to critical ICH phenomena. The topics include edge physics, fast wave propagation, ICH induced high frequency instabilities, and a preliminary antenna design for Ignitor. This research was strongly coordinated with the world's experimental and design teams at JET, Culham, ORNL, and Ignitor. The results have been widely publicized at both general scientific meetings and topical workshops including the speciality workshop on ICRF design and physics spo… more
Date: May 26, 1992
Creator: Aamodt, R. E.; Catto, P. J.; D'Ippolito, D. A.; Myra, J. R. & Russell, D. A.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Interferometric measurements of multilayer and double shell inertial fusion targets

Description: Optical interference microscopy plays an important role in the measurement of targets for inertial confinement fusion experiments. We describe how these techniques are applied to the measurement of thickness and refractive index of multilayer films on both flat substrates and microsphere targets. We also discuss procedures for manipulating and examining microsphere targets to measure defects and wall thickness variations anywhere on the target. Finally, we describe the use of optical interferom… more
Date: August 26, 1980
Creator: Weinstein, B.W.; Weir, J.T. & Willenborg, D.L.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Use of molecular beams to support microspheres during plasma coating

Description: Spherical laser fusion targets can be levitated on beams of Ar or other gas atoms. This is an especially useful and reliable technique for supporting microspheres during plasma coating or plasma etching. The reliability of this technique is principally the result of two things: the success of a special centering device which provides a lateral, stabilizing force on the levitated microspheres; and a gas handling system which is capable of controlling levitation gas flow in the microtorr liter/se… more
Date: August 26, 1980
Creator: Crane, J. K.; Smith, R. D.; Johnson, W. L.; Letts, S. A.; Korbel, G. R. & Krenick, R. M.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Structural Changes Observed in (Mo /sub 6/Ru /sub 4/)/sub x/B/sub 1-x/ Amorphous Alloys Observed with Positron Annihilation

Description: Changes in the structure of (Mo /sub 6/Ru /sub 4/)/sub x/B/sub 1-x/ amorphous alloys were observed in positron annihilation analysis using both positron lifetime and Doppler broadening techniques. The changes were introduced into the alloy either by varying the boron fraction or by neutron irradiation. Similar results were observed both in the irradiated alloys and those with vacant boron sites. The positron annihilation data suggest that the modified structure contains regions of open volume a… more
Date: March 26, 1982
Creator: Howell, R. H. & Johnson, W. L.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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THE CONTRIBUTION OF THE INDIVIDUAL RESONANCES TO THE RESONANCE INTEGRALS IN URANIUM AND THORIUM

Description: Information is presented in tabular form on the contributions of the individual resonances to the resonance integrals in U and Th. The cases considered are for isolated cylindrical rods and involve U/sup 238/, U/sup 238/O/ sub 2/, Th/ sup 232/, and Th/sup 232/O/sub 2/ (M.C.G.)
Date: October 26, 1961
Creator: Nordheim, L.W.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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[Bifurcations and Patterns in Nonlinear Dissifative Systems]

Description: This report discusses the following topics: Rayleigh-Benard convection with an imposed horizontal flow; Rayleigh-Benard convection in a gas under non-boussinesq conditions; electro- convection in a nematic liquid crystal; and Rayleigh-Benard convection in a nematic liquid crystal. (LSP)
Date: February 26, 1992
Creator: Ahlers, G. & Cannell, D. S.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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The DIII-D summary contribution to the final INTOR workshop

Description: In SIII-D, good H-mode confinement has been obtained with up to 6 MW of neutral-beam injection (NBI). In this report we summarize the essential features of divertor operation for DIII-D H-mode plasma. Briefly, our measurements show that: Large edge density and temperarture gradients are obtained with scale lengths of a few cm at the midplane; In the steady state, approximately 10-20% of the input power is deposited on the divertor plates in a region that is peaked on the separatrix and extends … more
Date: February 26, 1988
Creator: Hill, D. N.; Allen, S. L.; Brooks, N. H.; Content, D.; DeBoo, J. C.; Gohil, P. et al.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Biomodal spontaneous fission

Description: Investigations of mass and kinetic-energy distributions from spontaneous fission have been extended in recent years to an isotope of element 104 and, for half-lives, to an isotope of element 108. The results have been surprising in that spontaneous fission half-lives have turned out to be much longer than expected and mass and kinetic- energy distributions were found to abruptly shift away from those of the lighter actinides, showing two modes of fission. These new developments have caused a re… more
Date: September 26, 1989
Creator: Hulet, E.K. (Lawrence Livermore National Lab., CA (USA))
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Fabrication of a Set of Realistic Torso Phantoms for Calibration of Transuranic Nuclide Lung Counting Facilities

Description: A set of 16 tissue equivalent torso phantoms has been fabricated for use by major laboratories involved in counting transuranic nuclides in the lung. These phantoms, which have bone equivalent plastic rib cages, duplicate the performance of the DOE Realistic Phantom set. The new phantoms (and their successors) provide the user laboratories with a highly realistic calibration tool. Moreover, use of these phantoms will allow participating laboratories to intercompare calibration information, both… more
Date: October 26, 1983
Creator: Griffith, R. V.; Anderson, A. L.; Sundbeck, C. W. & Alderson, S. W.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Control of gas input and background pressure in the end plug regions of the TMX-U thermal barrier experiment

Description: Rate equations for the plasma species in a thermal barrier end plug establish an upper bound on the neutral pressure (P) external to the plasma. For the Tandem Mirror Experiment-Upgrade (TMX-U), this bound is P less than or equal to 0.5 - 1.0 x 10/sup -6/ Torr. Initially TMX-U did not satisfy this criterion, and axial end plugging of plasma losses seemed limited by the excessive pressure. Subsequently, we modified the machine to improve the vacuum conditions, decreasing P to the desired range. … more
Date: October 26, 1983
Creator: Turner, W. C.; Nexsen, W. E.; Allen, S. L.; Hooper, E. B.; Hunt, A. L.; Lang, D. D. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Positron-annihilation studies of molybdenum irradiated by protons, neutrons, or electrons

Description: Annealed molybdenum was irradiated at room temperature by energetic protons or neutrons and the fluence and recoil energy dependence of two traps was measured. Comparison of trapping rates with calculations of damage energy correlates high energy recoils with the short lifetime trap and low energy recoils with the longer lifetime.
Date: March 26, 1982
Creator: Howell, R.H.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Mechanical design criteria for continuously operating neutral beams

Description: A schematic of a neutral beam injector is shown. Neutral gas is injected into the ion source, where a discharge ionizes the gas. The ions are drawn from the source by an extractor grid and then accelerated to full energy by the accel grids. After acceleration the ions pass through the neutralizer cell. Once through the neutralizer cell, the beam consists of neutrals and ions. The ions traveling with the beam are space charge neutralized by background electrons. The grid which precedes the direc… more
Date: August 26, 1977
Creator: Vosen, S. R.; Bender, D. J.; Fink, J. H. & Lee, J. D.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Design considerations for a scintillating plate calorimeter for SDC

Description: As scintillating plate calorimetry is a viable option for the SDC detector, it is imperative that the phase space of passive and active materials be explored in a systematic fashion. To this end, we have examined several different configurations of passive and active materials as a function of incident energy, to see what the resolution and e/h characteristics are of each of these configurations. These studies have been carried out using the CALOR89 Monte Carlo simulation package. 3 figs., 5 ta… more
Date: July 26, 1991
Creator: Handler, T.; Job, P. K. & Gabriel, T. A.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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The response of a Fermilab-designed ion chamber in pulsed photon fields

Description: This note reports measurements of the response of a Fermilab-designed area monitor ionization chamber used in Chipmunk and Scarecrow detectors to pulsed photon fields of various intensities and durations. The measurements were made to better define the operating limits of the instruments and to understand the possible effects of recombination and space charge on the dose measured by the instruments in pulsed fields. 2 refs., 13 figs., 1 tab.
Date: January 26, 1988
Creator: Freeman, W.S.; Hartman, B.; Krueger, F. & Larson, J.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Liquid to gas leak ratios with liquid nitrogen and liquid helium

Description: To predict the leak rates of liquid helium and liquid nitrogen containers at operating conditions we need to know how small leaks (10/sup -8/ to 10/sup -5/ atm-cm/sup 3/ air/s), measured at standard conditions, behave when flooded with these cryogens. Two small leaks were measured at ambient conditions (approx.750 Torr and 295 K), at the normal boiling points of LN/sub 2/ and LHe, and at elevated pressures above the liquids. The ratios of the leak rates of the liquids at ambient pressure to the… more
Date: February 26, 1985
Creator: Batzer, T. H. & Call, W. R.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Nuclear performance optimization of the Be/Li/Th blanket for the fusion breeder

Description: More rigorous nuclear analysis, including treatment of resonance self-shielding effects coupled with an optimization procedure, has resulted in improved performance of the Be/Li/Th blanket. Net U-233 breeding ratio has increased 36% (to 0.84) while at an average U-233/Th ratio of 0.5 a/o average energy multiplication has increased only 12% (to 2.1) compared with earlier results.
Date: February 26, 1985
Creator: Lee, J. D. & Bandini, B. R.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Opportunistic replacement of fusion power system parts

Description: This paper describes a maintenance problem in a fusion power plant. The problem is to specify which life limited parts should be replaced when there is an opportunity. The objective is to minimize the cost rate of replacement parts and of maintenance actions while satisfying a power plant availability constraint. The maintenance policy is to look ahead and replace all parts that will reach their life limits within a time called a screen. Longer screens yield greater system availabilities becaus… more
Date: October 26, 1981
Creator: Day, J.A. & George, L.L.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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