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HIDE working groups. A. Synchrotron based system

Description: A summary is given of a week's discussions on an ion source to target scenario for a synchrotron for heavy ion fusion. Topics considered include: the number of beams on the target; beam dynamics; and a number of areas explicitly identified as needing further work. (PMA)
Date: January 1, 1977
Creator: Barton, M. Q.
Partner: UNT Libraries Government Documents Department
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Tandems as injectors for synchrotrons

Description: This is a review on the use of Tandem electrostatic accelerators for injection and filling of synchrotrons to accelerate intense beams of heavy-ions to relativistic energies. The paper emphasizes the need of operating the Tandems in pulsed mode for this application. It has been experimentally demonstrated that at the present this type of accelerators still provides the most reliable and best performance.
Date: January 1, 1992
Creator: Ruggiero, Alessandro G.
Partner: UNT Libraries Government Documents Department
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Solutions to heavy ion induced avalanche burnout in power devices

Description: Silicon power devices fall into two broad categories, bipolar and field effect. Transistors using both of these technologies are often used in satellite applications for power conversion. The present trend is toward integrating power transistors and control electronics on the same chip. In this case, it is the power portion of the chip that is most susceptible to burnout failures, because of it's high voltage operation. Hence, it is important to understand the operational limitations of power t… more
Date: January 1, 1991
Creator: Wrobel, T. F. & Beutler, D. E.
Partner: UNT Libraries Government Documents Department
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Aspects of the Physics, Chemistry, and Technology of High Intensity Heavy Ion Sources

Description: Particular emphasis is placed on the technology of plasma discharge ion sources which utilize solid elemental or molecular compounds to produce vapor for the ionization process. A brief discussion is made of the elementary concepts underlying the formation and extraction of ion beams from plasma discharge sources. A limited review of low charge state positive ion sources suitable for accelerator use is also given.
Date: January 1, 1980
Creator: Alton, G. D.
Partner: UNT Libraries Government Documents Department
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A fission source of radioactive heavy ions

Description: Fission products, formed following neutron capture by a target located in the moderator of a high-flux reactor, may be mass separated to provide intense beams of radioactive nuclei. These will span a broad mass range whose form will depend on the target element and on the presence of epithermal neutrons. Shorter lived activities may be used for beams and those with a longer half-life may be collected to form radioactive targets. Neutron fluxes as high as 10{sup 14} neutrons cm{sup -2}s{sup -1} … more
Date: January 1, 1989
Creator: Hamilton, W.D. (Oak Ridge National Lab., TN (USA) Vanderbilt Univ., Nashville, TN (USA). Dept. of Physics and Astronomy)
Partner: UNT Libraries Government Documents Department
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Interactions of fast atomic and molecular ions with matter

Description: Brief discussions are presented of research performed in the following areas: microwave field ionization of fast Rydberg atoms; electric field ionization of foil-excited Rydberg states of fast heavy ions; post-foil interaction in foil-induced molecular dissociation; and angular distributions of foil-excited ions bearing inner shell vacancies. 19 references. (GHT)
Date: January 1, 1984
Creator: Kanter, E. P.; Gemmell, D. S. & Vager, Z.
Partner: UNT Libraries Government Documents Department
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Low beta linacs

Description: A summary is given of discussions on the use of low-..beta.. linacs in a system for heavy ion fusion. Topics considered include: space charge limit; low-..beta.. linac structures; independently phased cavities; the Brookhaven low-..beta.. program; and rf deflectors for combining two linac beams. (PMA)
Date: January 1, 1977
Creator: Kustom, R.; Moretti, A.; Staples, J.; Khoe, T.K. & Keane, J.
Partner: UNT Libraries Government Documents Department
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TDHF for heavy ions

Description: The main consequences of the TDHF approximation are discussed and the present status of comparison with experimental data. It is intended that this will help to answer the question of whether the results obtained from the method are in reasonable proportion to the effort invested. 27 references. (JFP)
Date: January 1, 1979
Creator: Maruhn, J.A.
Partner: UNT Libraries Government Documents Department
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Heavy ion excitation of giant resonances: The next generation

Description: The prospects for high energy heavy ion excitation of giant resonances are discussed. A brief review is provided of the results obtained to date using low/medium energy heavy ions and it is suggested that those results show no substantial advantage of heavy ions for giant resonance excitation. Calculations are presented that show that Coulomb excitation becomes the dominant excitation mechanism of the giant resonances for heavy ions above about 100 MeV/nucleon. The Coulomb excitation provides e… more
Date: January 1, 1987
Creator: Bertrand, F.E.; Beene, J.R. & Horen, D.J.
Partner: UNT Libraries Government Documents Department
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Differential cross sections for electron emission in heavy ion-atom collisions

Description: The systematics of differential ionization cross sections are explored for incident charged particles which possess atomic structure. Although little has been published regarding outer shell ionization by structured projectiles, sufficient data are becoming available to provide some insight into the collision process. This discussion concentrates on systematics of emission cross sections for the intermediate and high energy projectiles where the applicability of high energy approximations can b… more
Date: January 1, 1978
Creator: Toburen, L. H.
Partner: UNT Libraries Government Documents Department
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Radio-frequency quadrupole: general properties and specific applications

Description: The radio-frequency quadrupole (RFQ) linac structure is being developed for the acceleration of low-velocity ions. Recent experimental tests have confirmed its expected performance and have led to an increased interest in a wide range of possible applications. The general properties of RFQ accelerators are reviewed and beam dynamics simulation results are presented for their use in a variety of accelerating systems. These include the low-beta sections of the Fusion Materials Irradiation Test Ac… more
Date: January 1, 1980
Creator: Stokes, R. H.; Crandall, K. R. & Hamm, R. W.
Partner: UNT Libraries Government Documents Department
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Radiation effects in space

Description: The paper discusses the radiation environment in space that astronauts are likely to be exposed to. Emphasis is on proton and HZE particle effects. Recommendations for radiation protection guidelines are presented. (ACR)
Date: January 1, 1986
Creator: Fry, R.J.M.
Partner: UNT Libraries Government Documents Department
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Imaging with a multiplane multiwire proportional chamber using heavy ion beams

Description: A 16-plane multiwire proportional chamber has been developed to accurately map intensity profiles of heavy ion beams at the Bevalac. The imaging capability of the system has been tested for reconstruction of 3-dimensional representation of a canine thorax region using heavy ion beams.
Date: January 1, 1982
Creator: Chu, W. T.; Alonso, J. R. & Tobias, C. A.
Partner: UNT Libraries Government Documents Department
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Focal spot size predictions for beam transport through a gas-filled reactor

Description: Results from calculations of focal spot size for beam transport through a gas-filled reactor are summarized. In the converging beam mode, we find an enlargement of the focal spot due to multiple scattering and zeroth order self-field effects. This enlargement can be minimized by maintaining small reactors together with a careful choice of the gaseous medium. The self-focused mode, on the other hand, is relatively insensitive to the reactor environment, but is critically dependent upon initial b… more
Date: January 23, 1980
Creator: Yu, S. S.; Lee, E. P. & Buchanan, H. L.
Partner: UNT Libraries Government Documents Department
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Experimental atomic physics in heavy-ion storage rings

Description: This paper outlines the discussion which took place at the ''round table'' on experimental atomic physics in heavy-ion storage rings. Areas of discussion are: electron-ion interactions, ion-ion collisions, precision spectroscopy of highly charged ions, beta decay into bound final states, and atomic binding energies from spectroscopy of conversion elections. 18 refs., 1 tab. (LSP)
Date: January 1, 1987
Creator: Datz, S.; Andersen, L.H.; Briand, J.P. & Liesen, D.
Partner: UNT Libraries Government Documents Department
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Status of RF superconductivity at Argonne

Description: Development of a superconducting (SC) slow-wave structures began at Argonne National Laboratory (ANL) in 1971, and led to the first SC heavy-ion linac (ATLAS - the Argonne Tandem-Linac Accelerating System), which began regularly scheduled operation in 1978. To date, more than 40,000 hours of bean-on target operating time has been accumulated with ATLAS. The Physics Division at ANL has continued to develop SC RF technology for accelerating heavy-ions, with the result that the SC linac has, up to… more
Date: January 1, 1989
Creator: Shepard, K.W.
Partner: UNT Libraries Government Documents Department
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Directions for Reactor Target Design Based on the U.S. Heavy Ion Fusion Systems Assessment

Description: We studied areas of major uncertainty in target design using the cost of electricity as our figure of merit. Net electric power from the plant was fixed at 1000 MW to eliminate large effects due to economies of scale. The system is relatively insensitive to target gain. Factors of three changes in gain cause only 8 to 12% changes in electricity cost. An increase in the peak power needed to drive targets poses only a small cost risk, but requires many more beamlets be transported to the target. … more
Date: January 1, 1986
Creator: Wilson, D. C.; Dudziak, D.; Magelssen, G.; Zuckerman, D. & Dreimeyer, D.
Partner: UNT Libraries Government Documents Department
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Radial Geometry Cesium Plasma Source With Improved Mechanical Features

Description: An improved version of the radial geometry cesium plasma negative ion source, described by Alton and Blazey, has been designed, evaluated and employed for use during routine operation of the Holifield Heavy Ion Research Facility (HHIRF) tandem accelerator. The mechanical features of the source have been improved to facilitate rapid change of degradable parts such as the sputter probe insulator and cathodes and to provide better thermal isolation of the externally mounted oven from the discharge… more
Date: January 1, 1985
Creator: Alton, G. D.; Beckers, R. M. & Johnson, J. W.
Partner: UNT Libraries Government Documents Department
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HIBP primary beam detector

Description: A position measuring detector was fabricated for the Heavy Ion Beam Probe. The 11 cm by 50 cm detector was a combination of 15 detector wires in one direction and 63 copper bars - .635 cm by 10 cm to measure along an orthogonal axis by means of a current divider circuit. High transmission tungsten meshes provide entrance windows and suppress secondary electrons. The detector dimensions were chosen to resolve the beam position to within one beam diameter.
Date: January 1, 1979
Creator: Schmidt, T.W.
Partner: UNT Libraries Government Documents Department
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Single and Multiple Electron Loss Processes in MeV Heavy Ion-Target Collisions

Description: Experimental data, derived from the study of interactions between MeV heavy ions and gaseous targets are presented which illustrate important physical aspects such as the dependence of cross sections on projectile velocity, and projectile and target atomic numbers. Included are data which reflect the importance of the electron binding energy, the existence of shell effects, the possibility of target polarizability, and the presence of non-additivity and density effects in electron loss processe… more
Date: January 1, 1980
Creator: Alton, G. D.
Partner: UNT Libraries Government Documents Department
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Dynamic versus Static Hadronic Structure Functions

Description: 'Static' structure functions are the probabilistic distributions computed from the square of the light-front wavefunctions of the target hadron. In contrast, the 'dynamic' structure functions measured in deep inelastic lepton-hadron scattering include the effects of rescattering associated with the Wilson line. Initial- and final-state rescattering, neglected in the parton model, can have a profound effect in QCD hard-scattering reactions, producing single-spin asymmetries, diffractive deep ine… more
Date: January 9, 2009
Creator: Brodsky, Stanley J.
Partner: UNT Libraries Government Documents Department
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Sorting chromatic sextupoles for easily and effectively correcting second order chromaticity in the Relativistic Heavy Ion Collider

Description: Based on the contributions of the chromatic sextupole families to the half-integer resonance driving terms, we discuss how to sort the chromatic sextupoles in the arcs of the Relativistic Heavy Ion Collider (RHIC) to easily and effectively correct the second order chromaticities. We propose a method with 4 knobs corresponding to 4 pairs of chromatic sextupole families to online correct the second order chromaticities. Numerical simulation justifies this method, showing that this method reduces … more
Date: January 2, 2009
Creator: Luo, Y.; Tepikian, S.; Fischer, W.; Robert-Demolaize, G. & Trbojevic, D.
Partner: UNT Libraries Government Documents Department
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Dynamic aperture evaluation of the proposed lattices for the RHIC 2009 polarized proton run

Description: In the article we evaluate the dynamic apertures of the proposed lattices for the coming Relativistic Heavy Ion Collider (RHIC) 2009 polarized proton (pp) 100 GeV and 250 GeV runs. One goal of this study is to find out the appropriate {beta}* for the coming 2009 pp runs. Another goal is to study the effect of second order chromaticity correction in the RHIC pp runs.
Date: January 2, 2009
Creator: Luo, Y.; Bai, M.; Beebe-Wang, J.; Fischer, W.; Montag, C.; Robert-Demolaize, G. et al.
Partner: UNT Libraries Government Documents Department
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