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A global fitting code for multichordal neutral beam spectroscopic data

Description: Knowledge of the heat deposition profile is crucial to all transport analysis of beam heated discharges. The heat deposition profile can be inferred from the fast ion birth profile which, in turn, is directly related to the loss of neutral atoms from the beam. This loss can be measured spectroscopically be the decrease in amplitude of spectral emissions from the beam as it penetrates the plasma. The spectra are complicated by the motional Stark effect which produces a manifold of nine bright pe… more
Date: May 1, 1992
Creator: Seraydarian, R.P.; Burrell, K.H. & Groebner, R.J.
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Partner: UNT Libraries Government Documents Department
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Observation of lines above 2000 A in OVIII and CVI in the PLT tokamak due to charge-exchange processes: diagnostic applications

Description: Hydrogen-like oxygen and carbon lines from high-n transitions with wavelengths above 2000 A were observed as a result of charge-exchange processes during neutral beam injection of hydrogen atoms into the Princeton Large Torus (PLT) tokamak. The lines are: OVIII 2976 A (8 ..-->.. 7 transitions), CVI 3434 A (7 ..-->.. 6), and CVI 5291 A (8 ..-->.. 7). Application of these lines for Doppler ion temperature measurements and initial obeservations of neutral beam vertical and horizontal distributions… more
Date: February 1984
Creator: Suckewer, S.; Skinner, C. H.; Stratton, B.; Bell, R.; Cavallo, A.; Hosea, J. et al.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Optical Pumping for Intense Polarized Ion Sources

Description: Laser optical pumping without buffer gas in dense (NL>10/sup 12/ atoms/cm/sup 2/) sodium vapor targets was investigated. The atomic polarization of the target was determined from the Faraday rotation angle of a second dye laser tuned midway between the sodium D-lines. Substantial polarizations were measured even though the pump laser bandwidth (approx. 1 MHz) was much smaller than the Doppler and hyperfine broadened sodium absorption line (approx. 3 GHz). Theoretical calculations based on rate … more
Date: January 1, 1982
Creator: Cornelius, W. D.; Taylor, D. J.; York, R. L. & Hinds, E. A.
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Partner: UNT Libraries Government Documents Department
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The AGS Booster vacuum systems

Description: The AGS Booster is a synchrotron for the acceleration of both protons and heavy ions. The design pressure of low 10{sup {minus}11} mbar is required to minimize beam loss of the partially stripped heavy ions. To remove contaminants and to reduce outgassing, the vacuum chambers and the components located in them will be chemically cleaned, vacuum fired, baked then treated with nitric oxide. The vacuum sector will be insitu baked to a minimum of 200{degree}C and pumped by the combination of sputte… more
Date: January 1, 1989
Creator: Hseuh, H. C.
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Partner: UNT Libraries Government Documents Department
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High energy negative deuterium beams using double charge-exchange or surface production

Description: Experimental and theoretical research on production of negative ion beams is described. Results from a double charge-exchange experiment include 10 ms pulses of 100 ma of D/sup -/ accelerated to 60 kV. Equilibrium fractions of D/sup -/ in several metal vapors are presented. Mechanisms and measurements of D/sup -/ on surfaces are described, and a scheme is shown for producing high current, high energy beams originating on surfaces.
Date: November 29, 1977
Creator: Hooper, E. B. Jr.; Anderson, O. A.; Orzechowski, T. & Poulsen, P.
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Partner: UNT Libraries Government Documents Department
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Effects of low-energy-electron-capture collisions (H/sub 0/ + c/sup n+/) on the particle and energy balance of tokamak plasmas

Description: To illustrate the way in which atomic data provides enlightenment in the search for understandable (and thus extrapolable) confinement models, we restrict our scope to electron capture collisions involving H/sub 0/ and multiply-charged ions. Many such foreign (impurity) multiply-charged ion species are found in plasma discharges, as a result of gas recycling and damage to the surrounding surfaces by energetic plasma particles. Typical low-Z ions are carbon and oxygen; the major constituents of … more
Date: January 1, 1981
Creator: Hogan, J. T.
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Partner: UNT Libraries Government Documents Department
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Density rise experiment on PLT

Description: The evolution of the density profile in PLT during intense gas puffing is documented and analyzed. Measurements of the spectrum of low energy edge neutrals and of the change in central neutral density indicate that charge-exchange processes alone cannot account for the central density rise. The transient density profile changes can be reproduced numerically by a diffusivity of approx. 10/sup 4/ cm/sup 2//s, and a spatially averaged inward flow of 10/sup 3/ cm/s. These transport coefficients are… more
Date: May 1, 1982
Creator: Strachan, J.D.; Bretz, N. & Mazzucato, E.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Status and future plans for the BNL polarized H/sup -/ source

Description: In 1982, when Haeberli described the design and performance of his 3 ..mu..A polarized negative hydrogen source, he predicted that the colinear colliding beam source had the potential to produce H/sup -/ beam currents well in excess of 10 ..mu..A. The recently constructed AGS source, which is similar to Haeberli's system, has reached peak beam currents in excess of 25 ..mu..A, while operating in the pulsed mode. Standard operation of the AGS machine is 10 ..mu..A in beam pulses of 0.5 ms each t… more
Date: January 1, 1983
Creator: Sluyters, T.; Alessi, J. & Kponou, A.
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Partner: UNT Libraries Government Documents Department
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Ionization of polarized hydrogen atoms

Description: Methods are discussed for the production of polarized H/sup -/ ions from polarized atoms produced in ground state atomic beam sources. Present day sources use ionizers of two basic types - electron ionizers for H/sup +/ Vector production followed by double charge exchange in a vapor, or direct H/sup -/ Vector production by charge exchange of H/sup 0/ with Cs/sup 0/. Both methods have ionization efficiencies of less than 0.5%. Ionization efficiencies in excess of 10% may be obtained in the futur… more
Date: January 1, 1983
Creator: Alessi, J.G.
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Partner: UNT Libraries Government Documents Department
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Propagation of a heavy ion beam in gas-filled reactor

Description: A heavy ion beam traversing a gas-filled reactor is stripped of its electrons along its path. The propagation of the stripping beam with possible associated instabilities has been investigated.
Date: November 3, 1977
Creator: Yu, S. S.; Buchanan, H. L.; Chambers, F. W. & Lee, E. P.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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He/sup + +/ transport in the PDX tokamak

Description: A powerful new approach to the study of particle transport and helium ash confinement in high-temperature fusion plasmas is demonstrated by charge-exchange recombination spectroscopy of He/sup + +/ in ohmically heated PDX discharges. Time and space resolved measurements of He/sup + +/ density following a short puff of helium gas into the plasma edge are fitted using a diffusive/convective transport model with coefficients D = (2.1 +- 0.9) x 10/sup 4/ cm/sup 2/ s/sup -1/ and v(r)/D = (0.8 +- 0.3… more
Date: December 1, 1983
Creator: Fonck, R.J. & Hulse, R.A.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Negative beam generation, transport, and acceleration

Description: A negative ion beam, generated by double charge exchange, has been accelerated to 60 keV. The components of the beamline are described, and an analysis of the flow and the effect of the beam-generated plasma is presented. It is shown that plasma flow along the beamline is limited by transverse ambipolar transport; acceleration of electrons can therefore be minimized by employing a drift space to control the flow of electrons from the cesium cell to the accelerator entrance.
Date: October 1, 1977
Creator: Poulsen, P.; Anderson, O. A.; Hooper, E. B. Jr.; Orzechowski, T. J. & Turnbull, R. J.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Low energy electron capture by multicharged ions from hydrogen

Description: In order to systematically investigate the behavior of low energy electron capture cross sections, the cross sections were measured for Xe/sup 2 +/ - Xe/sup 12 +/, Ar/sup 2 +/ - Ar/sup 9 +/, and Fe/sup 5 +/ - Fe/sup 6 +/ in H and H/sub 2/ for 3 < E < 26 keV/charge, and for C/sup 3 +/ - C/sup 5 +/ in H/sub 2/ for 0.15 < E < 0.45 keV/charge. (GHT)
Date: January 1, 1980
Creator: Phaneuf, R.A.; Crandall, D.H. & Meyer, F.W.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Antinucleon physics

Description: Some of the recent data from LEAR, Brookhaven, and KEK on low and medium energy interactions of antinucleons (anti N) with nucleons (N) are reviewed and interpreted. Emphasis is on elastic and charge exchange scattering, total cross sections, and studies of anti NN annihilation, with particular focus on the emerging evidence for broad resonances and/or bound states of the anti NN system and the selection rules which reveal the quuark-gluon dynamics of the annihilation process. 69 refs., 8 figs.
Date: January 1, 1986
Creator: Dover, C. B.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Radio-frequency He/sup -/ source and a source of negative ions by cesium sputtering

Description: Two sources of negative ions are described. An rf source produces up to 14 ..mu..A beams of He/sup -/ by charge exchange in Rb vapor. The other Source of Negative Ions by Cesium Sputtering (SNICS) produces a wide variety of negative ion beams in the ..mu..A range. Two important features of SNICS are its simple, compact construction and its very good beam emittance (2 to 4 ..pi..mm mrad MeV/sup 1/). Both sources have lifetimes >200 hours and they are used extensively on the Wisconsin EN tandem.
Date: January 1, 1980
Creator: Billen, J.H.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Plasma diagnostic techniques using particle beam probes

Description: A brief overview is given of particle beam probing. The fundamental concepts common to all techniques are discussed as well as the design considerations for choosing a particular diagnostic technique. The capabilities of existing and proposed techniques, and the present status of the techniques in major magnetic confinement geometries is also presented. Techniques which involve the injection of a beam of neutral particles into the plasma are then considered. The techniques of beam attenuation, … more
Date: July 1, 1980
Creator: Jennings, W. C.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Hydrogen recycle modeling and measurements in tokamaks and EBT

Description: A model for hydrogen recycling developed for use in a Tokamak transport code is described and compared with measurements on ISXB and DITE. The model includes kinetic reflection of charge-exchange neutrals from the wall and deposition, thermal diffusion and desorption processes in the wall. In a Tokamak with a limiter, the inferred recycle coefficient of 0.9 to 1.0 is due primarily to reflection (0.8 to 0.9) with the remainder (0.1 to 0.2) being due to desorption. Laboratory experiments supply m… more
Date: January 1, 1980
Creator: Howe, H.C.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Learning from numerical calculations of ion-atom collisions

Description: Violent collision of two independent many-particle systems, victims, are discussed in the atomic sphere. The asymmetric region where the charge of the projectile Z/sub p/ is less than the target nuclear charge Z/sub n/ is now well understood though interesting details still need to be worked out. Negatively charged projectiles offer a new illustration of Fadeev re-arrangement collisions. Multi-electron coherence effects illustrate the richness of the field but a symmetric (Z/sub p/ approx. Z/su… more
Date: January 1, 1981
Creator: Reading, J.F.; Ford, A.L.; Martir, M. & Becker, R.L.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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LASL high-current proton storage rings

Description: The Proton Storage Ring at LAMPF is a high-current accumulator designed to convert long 800-MeV linac pulses into very short high-intensity proton bunches ideally suited to driving a pulsed polyenergetic neutron source. The Ring, authorized for construction at $19 million, will operate in a short-bunch high-frequency mode for fast neutron physics and a long-bunch low-frequency mode for thermal neutron-scattering programs. Unique features of the project include charge-changing injection with ini… more
Date: January 1, 1980
Creator: Lawrence, G. P.; Cooper, R. K.; Hudgings, D. W.; Spalek, G.; Jason, A. J.; Higgins, E. F. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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