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Measurements of energetic helium-3 minority distributions during ion cyclotron radio-frequency heating in the Princeton Large Torus

Description: Ion cyclotron radio-frequency heating experiments were performed with a /sup 3/He minority ion species in a /sup 4/He majority plasma in the Princeton Large Torus. The energetic /sup 3/He ion ''tail'' was measured directly with a charge exchange neutral analyzer for the first time. Comparisons with bounce-averaged quasi-linear calculations suggest a modestly peaked radi-frequency power deposition profile. The double charge exchange process /sup 3/He/sup + +/ )plus) /sup 4/He/sup 0/ )plus) /sup … more
Date: March 1, 1988
Creator: Hammett, G. W.; Kaita, R. & Wilson, J. R.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Properties of hydrogen/helium accretion plasmas

Description: We study the properties of impulsively-heated plasmas initially composed of hydrogen and helium. We follow the time-dependent behavior of the ion and electron temperatures, the pair density, and the densities of hydrogen, helium, and nuclei formed in fusion and breakup reactions. We also consider neutron production and escape, and calculate the 0.431 and 0.478 MeV line luminosities from ..cap alpha..-..cap alpha.. fusion reactions, and the 2.22 MeV line luminosity from neutron capture on proton… more
Date: February 1, 1988
Creator: Guessoum, N. & Dermer, C. D.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Fusion core start-up, ignition and burn simulations of reversed-field pinch (RFP) reactors

Description: A transient reactor simulation model is developed to investigate and simulate the start-up, ignition and burn of a reversed-field pinch reactor. The simulation is based upon a spatially averaged plasma balance model with field profiles obtained from MHD quasi-equilibrium analysis. Alpha particle heating is estimated from Fokker-Planck calculations. The instantaneous plasma current is derived from a self-consistent circuit analysis for plasma/coil/eddy current interactions. The simulation code i… more
Date: January 1, 1988
Creator: Chu, Yuh-Yi
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Very-High Energy (E. --> E beam) Light Particle Production Near O° in Heavy-Ion Collisions, E/A Less Than or Equal to 40 MeV/u

Description: Studies of heavy-ion collisions at E/A approx. 10 MeV/u to 20 MeV/u with the production of nucleons and other particles at forward angles with velocities several times that of the projectile have been observed by many groups (TAM, ORNL, MSU, HMI). This is usually attributed to projectile fragmentation with Fermi motion of the light particle which is often described by a source temperature T/sub s/, accounting for the additional velocity component. However, experiments reported by Borcea et al. … more
Date: February 1, 1988
Creator: Shaheen, S.; Becchetti, F. D.; Roberts, D.; Jaenecke, J.; Schulman, P.; Stern, R. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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First direct measurement of alpha--muon sticking in deuteron triton--muon-catalyzed fusion

Description: Both (..cap alpha mu..)/sup +/ and ..cap alpha.. particles have been observed in coincidence with fusion neutrons in a gaseous D--T target at 2.8 /times/ 10/sup /minus/3/ liquid-hydrogen density. The initial muon sticking probability in muon-catalyzed d--t fusion, measured directly for the first time, is (0.80 +- 0.15 +- 0.12 systematic)/percent/ in agreement with 'standard' theoretical calculations. However, this measured value does not support those theories that invoke special mechanisms to … more
Date: January 1, 1988
Creator: Paciotti, M. A.; Baker, O. K.; Bradbury, J. N.; Cohen, J. S.; Leon, M.; Maltrud, H. R. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Four-channel ZnS scintillator measurements of escaping tritons in TFTR

Description: A four-channel scintillation detector capable of measuring tritons, protons, and alphas escaping from a tokamak plasma was operated during the 1986 run period of the Tokamak Fusion Test Reactor (TFTR). Signals consistent with the expected 1 MeV triton behavior have been observed during deuterium operation. Backgrounds associated with neutrons, gammas, and soft x-rays have been evaluated in situ. Such a detector should be capable of measuring escaping alphas during the D/T phase of TFTR. 16 refs… more
Date: October 1, 1988
Creator: Zweben, S. J.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Alpha storage regime in high temperature sub-ignited D-T tokamaks

Description: Alpha particle parameters in sub-ignited D-T tokamaks like TFTR can be optimized in a high temperature ''alpha storage regime '' in which the alpha particle thermalization time /tau//sub ..cap alpha../ is long (approx.1.0 sec) and in which the alpha particle source rate S/sub ..cap alpha../ is enhanced due to a beam-target and beam-beam reactions (by a factor of approx.2-3). Near reactor-level alpha instability parameters ..beta../sub ..cap alpha../(0) approx. n/sub ..cap alpha../(0)/n/sub e/(O… more
Date: July 1, 1988
Creator: Zweben, S. J.; Furth, H. P.; Mikkelsen, D. R.; Redi, M. H. & Strachan, J. D.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Transport and stability studies on TFTR

Description: During the 1987 run, TFTR reached record values of Q/sub DD/, neutron source strength, and T/sub i/(0). Good confinement together with intense auxiliary heating has resulted in a plasma pressure greater than 3 x 10/sub 5/ Pascals on axis, which is at the ballooning stability boundary. At the same time improved diagnostics, especially ion temperature profile measurements, have led to increased understanding of tokamak confinement physics. Ion temperature profiles are found to be much more peaked… more
Date: October 1, 1988
Creator: McGuire, K.M.; Arunasalam, V.; Barnes, C.W.; Bell, M.G.; Bitter, M.; Bosch, H.S. et al.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Alpha, silicon, and iron ion induced current transients in low capacitance silicon and GaAs diodes

Description: High-speed (<40 ps) current transient and charge collection measurements were make using a wide-band 70-GHz, 6-ps risetime sampling oscilloscope, on GaAs and silicon diodes irradiated by 18 MeV Si, 12 MeV B, 12 and 100 MeV Fe ions, and 3 and 5 MeV alpha particles. Results show that the response of a device to a particle strike can be very fast but strongly depends on the LET (Linear Energy Transfer) of the particle. The rise time dependence with different parameters such as the doping density, … more
Date: January 1, 1988
Creator: Wagner, R. S.; Bordes, N.; Bradley, J. M.; Maggiore, C. J.; Knudson, A. & Campbell, A.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Hypernuclear interactions and the binding energies of and hypernuclei

Description: By use of variational calculations a reasonable hadronic description is obtained of the s-shell hypernuclei, of /sub /ZBe, and of the well depth, with N forces which are consistent with p scattering and which are quite strongly spin-dependent, with reasonable TPE NN forces with strongly repulsive dispersive-type NN forces. For the latter we also consider a spin-dependent version which is somewhat favored by our analysis. /sub /ZBe is treated as a 2ed + system and is significantly overbound, app… more
Date: January 1, 1988
Creator: Bodmer, A. R. & Usmani, Q. N.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Calculated /alpha/-induced thick target neutron yields and spectra, with comparison to measured data

Description: One component of the neutron source associated with the decay of actinide nuclides in many environments is due to the interaction of decay /alpha/ particles in (/alpha/,n) reactions on low Z nuclides. Measurements of (/alpha/,n) thick target neutron yields and associated neutron spectra have been made for only a few combinations of /alpha/ energy and target nuclide or mixtures of actinide and target nuclides. Calculations of thick target neutron yields and spectra with the SOURCES code require … more
Date: January 1, 1988
Creator: Wilson, W. B.; Bozoian, M. & Perry, R. T.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Monte Carlo alpha deposition

Description: Prior work demonstrated the importance of nuclear scattering to fusion product energy deposition in hot plasmas. This suggests careful examination of nuclear physics details in burning plasma simulations. An existing Monte Carlo fast ion transport code is being expanded to be a test bed for this examination. An initial extension, the energy deposition of fast alpha particles in a hot deuterium plasma, is reported. The deposition times and deposition ranges are modified by allowing nuclear scatt… more
Date: January 1, 1988
Creator: Talley, T. L. & Evans, F.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Plasma diagnostics for the compact ignition tokamak

Description: The primary mission of the Compact Ignition Tokamak (CIT) is to study the physics of alpha-particle heating in an ignited D-T plasma. A burn time of about 10 /tau//sub E/ is projected in a divertor configuration with baseline machine design parameters of R=2.10 m, 1=0.65 m, b=1.30 m, I/sub p/=11 MA, B/sub T/=10 T and 10-20 MW of auxiliary rf heating. Plasma temperatures and density are expected to reach T/sub e/(O) /approximately/20 keV, T/sub i/(O) /approximately/30 keV, and n/sub e/(O) /appro… more
Date: June 1, 1988
Creator: Medley, S. S. & Young, K. M.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Alpha-particle effects on high-n instabilities in tokamaks

Description: Hot ..cap alpha..-particles and thermalized helium ash particles in tokamaks can have significant effects on high toroidal mode number instabilities such as the trapped-electron drift mode and the kinetically calculated magnetohydrodynamic ballooning mode. In particular, the effects can be stabilizing, destabilizing, or negligible, depending on the parameters involved. In high-temperature tokamaks capable of producing significant numbers of hot ..cap alpha..-particles, the predominant interacti… more
Date: June 1, 1988
Creator: Rewoldt, G.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Some applications of Photon/Electron-Rejecting Alpha Liquid Scintillation (PERALS) spectrometry to the assay of alpha emitters

Description: The combination of certain solvent extraction separations and a special kind of liquid scintillation detector and electronics designed for alpha spectrometry allows some highly accurate, yet simple determinations of alpha-emitting nuclides. Counting efficiency is 99.68% with backgrounds of <0.02 cpm. Energy resolution and peak position are sufficient for the identification of many nuclides. Rejection of interference from ..beta.. and ..gamma.. radiation is >99.95%. The Photon/Electron Rejecting… more
Date: January 1, 1988
Creator: McDowell, W.J. & Case, G.N.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Geohydrologic characterization of the area surrounding the 183-H Solar Evaporation Basins

Description: The purpose of this investigation is to achieve regulatory compliance with the applicable ground-water monitoring requirements of the Resource Conservation and Recovery Act (RCRA) and the Washington Administrative Code (WAC). An assessment-level compliance monitoring project was established for the 183-H Basins because hazardous waste constituents were known to have entered the ground water beneath the facility. Three phases were defined for this project, with work being concentrated in five ar… more
Date: December 1, 1988
Creator: Liikala, T. L.; Aaberg, R. L.; Aimo, N. J.; Bates, D. J.; Gilmore, T. J.; Jensen, E. J. et al.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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A CO/sub 2/ laser Thomson scattering diagnostic for fusion product alpha particle measurement

Description: A description of a CO/sub 2/ laser Thomson scattering diagnostic for fusion alpha particles is presented. Scattering calculations based on CIT plasma parameters are presented and compared to previous work based on TFTR parameters. Systems components are described and a proof-of-principle test in a nonburning plasma is discussed. 8 refs., 3 figs., 1 tab.
Date: January 1, 1988
Creator: Richards, R. K.; Bennett, C. A.; Fletcher, L. K.; Hunter, H. T. & Hutchinson, D. P.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Alpha particle confinement in tokamaks

Description: An assessment of diffusive tokamak transport mechanisms of concern for alpha particles indicates that the ''stochastic regime'' is the only one which appears to pose a real danger for adequate alpha confinement. This fact, in conjunction with the threshold character of that mechanism, allows one to decide whether an alpha born at a given location will be lost or confined, according to a very simple criterion. Implementing this criterion numerically results in a new code for the assessment of al… more
Date: November 1, 1988
Creator: White, R. B. & Mynick, H. E.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Green's function Monte Carlo calculations of /sup 4/He

Description: Green's Function Monte Carlo methods have been developed to study the ground state properties of light nuclei. These methods are shown to reproduce results of Faddeev calculations for A = 3, and are then used to calculate ground state energies, one- and two-body distribution functions, and the D-state probability for the alpha particle. Results are compared to variational Monte Carlo calculations for several nuclear interaction models. 31 refs.
Date: January 1, 1988
Creator: Carlson, Joseph A.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Does plutonium intake in workers affect lymphocyte function

Description: Measurements of mononuclear cells in peripheral blood of persons with long term internal depositions of plutonium indicate a preferential reduction in suppressor T-lymphocytes (T/sub s/) in some individuals. The decrease in T/sub s/ cells is apparently due to altered radiosensitivity, which is domonstrated in cultured cells subjected to in vitro x-ray radiation. The increase in ratios correlates with the quantity of plutonium deposition in these subjects, but there are wide individual differenc… more
Date: January 1, 1988
Creator: Voelz, George L.; Stevenson, Anita P. & Stewart, Carleton C.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Fusion Energy Division: Annual progress report, period ending December 31, 1987

Description: The Fusion Program of Oak Ridge National Laboratory (ORNL), a major part of the national fusion program, carries out research in nearly all areas of magnetic fusion. Collaboration among staff from ORNL, Martin Marietta Energy Systems, Inc., private industry, the academic community, and other fusion laboratories, in the United States and abroad, is directed toward the development of fusion as an energy source. This report documents the program's achievements during 1987. Issued as the annual pro… more
Date: November 1, 1988
Creator: Morgan, O. B., Jr.; Berry, L. A. & Sheffield, J.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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