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in subjects: "Heavy Ions"  
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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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The Booster-to-AGS Beam Transfer Fast Kicker Modulators

Description: This work describes modulator developments for the Brookhaven Booster extraction and the AGS injection fast kickers. The modulators are projected for both proton and heavy ion operation. The equivalent load inductance is about 2.1 to 2.3 {mu}H for each modulator. The PFN voltage is required to be below 40 kV for operation in air. The rise time of the pulse for proton beam transfer is 120 ns up to 97% of full current (1000 A), and for heavy ion beam transfer, the requirement is 160 ns up to 98% … more
Date: January 1, 1991
Creator: Zhang, W.; Bunicci, J.; Frey, W. W.; Soukas, A. V. & Zhang, S. Y.
Partner: UNT Libraries Government Documents Department
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Design Aspects for a Pulsed-Mode, High-Intensity, Heavy Negative Ion Source

Description: A high-intensity, plasma-sputter, negative ion source, which utilizes multi-cusp, magnetic-field, plasma-confinement techniques, has been designed at the Oak Ridge National Laboratory (ORNL). The source is an axial-geometry version of the radial-geometry source which has demonstrated pulsed-mode peak intensity levels of several mA for a wide spectrum of heavy negative ion species. The mechanical design features include provisions for fast interchange of sputter samples, ease of maintenance, dir… more
Date: January 1, 1991
Creator: Alton, G. D.
Partner: UNT Libraries Government Documents Department
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Construction and early commissioning results of the AGS Booster

Description: The AGS Booster synchrotron has been designed to accelerate protons from 200 MeV to 1.5 GeV and heavy ions from several MeV per nucleon to several hundred MeV per nucleon for all the nuclei up to gold. The design requirements and measurements results of major accelerator components and systems are presented. The early commissioning results of the injection is also presented. 12 refs., 9 figs., 2 tabs.
Date: January 1, 1991
Creator: Weng, W. T.; Ahrens, L.; Damm, R. & McNerney, A. J.
Partner: UNT Libraries Government Documents Department
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An experiment to study strong electromagnetic fields at RHIC

Description: We present a description of an experiment which can be used to search for effects of strong electromagnetic fields on the production of e{sup +}e{sup {minus}} pairs in the elastic scattering of two heavy ions at RHIC. A very brief discussion of other possible studies of electromagnetic phenomena at RHIC is also presented.
Date: January 1, 1990
Creator: Fatyga, M. (Brookhaven National Lab., Upton, NY (USA)) & Norbury, J.W. (Rider Coll., Lawrenceville, NJ (USA). Dept. of Physics)
Partner: UNT Libraries Government Documents Department
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The design of the RF cavity for the heavy ion storage ring for atomic physics

Description: An rf cavity and drive system have been designed for the proposed Heavy Ion Storage Ring for Atomic Physics,'' HISTRAP, at Oak Ridge. A peak accelerating voltage of 2.5 kV per turn is required with a continuous tuning range from 200 kHz through 2.7 MHz. A single-gap, half-wave resonant configuration is used with biased ferrite tuning. The cavity structure is completely outside of the beam line/vacuum enclosure except for a single rf window that serves as an accelerating gap. Physical separation… more
Date: January 1, 1990
Creator: Mosko, S.W.
Partner: UNT Libraries Government Documents Department
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Ecr (Electron Cyclotron Resonance) Source for the HHIRF (Holifield Heavy Ion Research Facility) Tandem Accelerator

Description: Electron Cyclotron Resonance, ECR, ion source technology has developed rapidly since the original pioneering work of R. Geller and his group at Grenoble in the early 1970s. These ion sources are capable of producing intense beams of highly charged positive ions and are used extensively for cyclotron injection, linac injection, and atomic physics research. In this paper, the advantages of using an ECR heavy-ion source in the terminal of the Holifield Heavy Ion Research Facility (HHIRF) 25-MV tan… more
Date: January 1, 1990
Creator: Olsen, D. K.; Alton, G. D.; Dowling, D. T.; Haynes, D. L.; Jones, C. M.; Juras, R. C. et al.
Partner: UNT Libraries Government Documents Department
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Studies of structural damage in high-[Tc] superconductors by high-energy heavy-ion irradiation

Description: The results of studies of structural damage by high-energy (MeV) Si[sup +13], Cu[sup +18], Ag[sup +21], and Au[sup +24] ions, using transmission electron microscopy techniques, revealed that the size of the damaged area (amorphous) is strongly dependent on: (1) the stopping power [dE/dx (keV/nm)] of the irradiating ions, (2) the thermal diffusivity of the crystal, (3) the degree of oxygenation, in the case of YBa[sub 2]Cu[sub 3]O[sub 7-[delta]], and (4) the direction of the ion beam with respec… more
Date: January 1, 1992
Creator: Zhu, Yimei; Cai, Z.X.; Budhani, R.C.; Welch, D.O. & Suenaga, M.
Partner: UNT Libraries Government Documents Department
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First operational experience with the positive-ion injector of ATLAS

Description: The recently completed positive-ion injector for the heavy-ion accelerator ATLAS was designed as a replacement for the tandem injector of the present tandem-linac system and, unlike the tandem, the positive-ion injector is required to provide ions from the full range of the periodic table. The concept for the new injector, which consists of an ECR ion source on a voltage platform coupled to a very-low-velocity superconducting linac, introduces technical problems and uncertainties that are well … more
Date: January 1, 1992
Creator: Bollinger, L. M.; Pardo, R. C.; Shepard, K. W.; Bogaty, J. M.; Clifft, B. E.; Munson, F. H. et al.
Partner: UNT Libraries Government Documents Department
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The operational status of the Booster injector for the AGS accelerator complex at BNL

Description: The Booster synchrotron at Brookhaven National Laboratory has been incorporated into the accelerator chain at the Alternating Gradient Synchrotron (AGS) complex. After a successful first commissioning effort in the spring of 1991, the Booster has been part of this year's silicon, gold and proton physics runs. After a brief review of the Booster design goals, and of the early commissioning, this paper will summarize this year's activities.
Date: January 1, 1992
Creator: Ahrens, L.; Bleser, E.; Brennan, J. M.; Gardner, C.; Gill, E.; Glenn, J. W. et al.
Partner: UNT Libraries Government Documents Department
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Design and test of a superconducting RFQ for heavy ions

Description: A prototype SRFQ resonator optimized for a velocity of [beta]=0.03 and a charge to mass ratio (q/M) of 1/6 has been designed, fabricated and tested. This is a short RFQ structure (only 2[beta][lambda] long) operating at 57.4MHz. The resonator is made of copper, and a 1.5[mu]m thick layer of electroplated Pb-2at.%Sn is used as the superconductor. The electrical characteristics of the resonator derived from detailed 3-D numerical simulations using the MAFIA codes, and also from measurements on th… more
Date: January 1, 1992
Creator: Ben-Zvi, Ilan; Jain, A.; Noe, J. W.; Paul, P.; Wang, H. & Lombardi, A.
Partner: UNT Libraries Government Documents Department
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Trace contamination measurements using heavy ion backscattering spectrometry

Description: Heavy Ion Backscattering Spectrometry (HIBS) is a tool for measuring surface contamination at levels much lower than previously achievable with ion beam analyses. Many areas of materials research and development require very low levels of impurities, with advanced microelectronics as the best example. HIBS uses low-energy, heavy ions for analysis, taking advantage of the increased backscattering yield which can be obtained from high Z ion beams at low energy. Background due to increased yield f… more
Date: January 1, 1995
Creator: Knapp, J. A.; Banks, J. C. & Brice, D. K.
Partner: UNT Libraries Government Documents Department
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High-resolution heavy-ion-induced x-ray satellite emission study of implanted sulfur as a probe of co-implanted oxygen in an oxide substrate

Description: Using high-resolution measurements, the relative fluorescence yields of the sulfur K{sub {alpha}}L{sup n} x-ray satellite lines produced by 24 MeV Si{sup q+} ion irradiation of a series of quartz glass targets co-implanted to equal doses and depths of sulfur and oxygen have been obtained and compared to the yields from a series of quartz glass targets implanted to the same depth with sulfur only. The data exhibit lower yields in the higher-order KL{sup n} satellite lines for the co-implanted ox… more
Date: January 1, 1990
Creator: Rosseel, T. M.; Young, J. P.; Vane, C. R.; Zuhr, R. A. & Peterson, R. S.
Partner: UNT Libraries Government Documents Department
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On the determination of loop nature in the TEM

Description: The two direct methods available for determining the nature of small clusters, were studied. Experiments in heavy-ion irradiated Ag and Cu, including comparisons with Black-White contrast analysis (B-W), forced us to conclude that use of the 2-1/2D technique for analysis of faulted loops is impossible because of reciprocal-lattice spike and other effects. We used B-W analysis to study the clusters produced by RT heavy-ion irradiation of Cu. In-situ irradiations were performed in Argonne HVEM-Ta… more
Date: January 1, 1997
Creator: Jenkins, M.L.; Fukushima, H. & Kirk, M.A.
Partner: UNT Libraries Government Documents Department
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