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The (t,d) reaction on the Ni isotopes with polarized tritons

Description: The (t vector,d) reaction has been measured on targets of /sup 58/ /sup 60/ /sup 62/ /sup 64/Ni with 17 MeV polarized tritons. Spectroscopic factors, angular momentum and total spin transfer were obtained from the differential cross section and A/sub y/ values of levels up to 3.5 MeV in excitation energy. The present (t,d) measurement enables a better description of the 9/2/sup +/ and 5/2/sup +/ states which show significant shell crossing effects as a function of increasing neutron number.
Date: January 1, 1980
Creator: Flynn, E. R.; Cizewski, J. A.; Brown, R. E.; Hardekopf, R. A. & Sunier, J. W.
Partner: UNT Libraries Government Documents Department
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Use of molybdenum ion source electrodes at RTNS-II

Description: Reports are reported for an ongoing effort to optimize D+ beam production by the MATS-III ion source used at RTNS-II. The three seven-aperture electrodes, originally consisting of water-cooled copper, have now been tested using uncooled molybdenum and with water cooling on the second (decel) electrode only. Details of the change, the results of the testing, and the benefits in operation, performance and cost are given.
Date: September 29, 1986
Creator: Massoletti, D.J.; Harter, G.A. & Heikkinen, D.W.
Partner: UNT Libraries Government Documents Department
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Development of a low intensity current monitor system

Description: This report documents the development of a current transformer system used to measure pulsed ion beam currents with a wide dynamic intensity range (nA to mA, and factor of 10{sup 6}). Peak beam currents at the LAMPF accelerator typically range from 100 to nA to 40 mA with pulse widths varying from 30 to 1000 {mu}s. Signal conditioning of the peak current output provides an average current readout with a range of 1 nA to 2 mA, noise of approximately {plus minus}0.5 nA, and accuracy of {plus minu… more
Date: January 1, 1991
Creator: Gallegos, F.R.
Partner: UNT Libraries Government Documents Department
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Modeling studies on the precipitation of Kr after implantation into metals

Description: A rate-theory approach is applied to interpreting observations on the precipitation of Kr injected into Ni at temperatures between 25 and 560/degree/C. At temperatures of 400/degree/C or higher, the implanted Kr precipitates evolve into a bi-modal size distribution containing small solid precipitates and an additional population of larger, faceted bubbles. The calculations explore the dependence of the observed bi-modal distribution on the maximum size of the solid Kr precipitates and the effec… more
Date: February 1, 1988
Creator: Rest, J.
Partner: UNT Libraries Government Documents Department
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Estimate of the longitudinal self electric field of an ion beam

Description: The self electric field on the axis of an ion beam of radius a in a conducting cylinder of radius b is given. The formula assumes that the radius of the conducting cylinder is much smaller than the length of the ion beam (b much less than L) and that E/sub z/ is calculated away from the edge of the beam (vertical bar z vertical bar less than vertical bar L/2 vertical bar). For the HIDE parameters, i.e., loosely speaking a 50 TW, 100 JK, multi-GeV heavy ion beam, the assumption b much less than … more
Date: January 1, 1977
Creator: Irani, A.A.
Partner: UNT Libraries Government Documents Department
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Magnetic fusion with high energy self-colliding ion beams

Description: Field-reversed configurations of energetic large orbit ions with neutralizing electrons have been proposed as the basis of a fusion reactor. Vlasov equilibria consisting of a ring or an annulus have been investigated. A stability analysis has been carried out for a long thin layer of energetic ions in a low density background plasma. There is a growing body of experimental evidence from tokamaks that energetic ions slow down and diffuse in accordance with classical theory in the presence of lar… more
Date: June 1, 1992
Creator: Rostoker, N.; Wessel, F. (California Univ., Irvine, CA (United States)); Maglich, B. (Advanced Physics Corp., Irvine, CA (United States)) & Fisher, A. (Naval Research Lab., Washington, DC (United States))
Partner: UNT Libraries Government Documents Department
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Vacuum considerations summary

Description: The vacuum system for Heavy Ion Fusion machines can be divided according to pressure into 4 parts: (a) Ion Sources; (b) Linear Accelerators; (c) Circular Accelerators, Accumulators and Storage Rings; and (d) Reactors. Since ion sources will need rather conventional pumping arrangements and reactors will operate with greater pressures, depending on their mode of operation, only items b and c will be treated in this report. In particular, the vacuum system design will be suggested for the machine… more
Date: January 1, 1977
Partner: UNT Libraries Government Documents Department
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A many particle-tracking detector with drift planes and segmented cathode readout

Description: We describe the design and performance of a detector system for tracking charged particles in an environment of high track density and rates up to 1 MHz. The system operates in the forward spectrometer of the BNL Heavy Ion experiment E814 and uses principles of general interest in high rate, high multiplicity applications such as at RHIC or SSC. We require our system to perform over a large dynamic range, detecting singly charged particles as well as fully ionized relativistic {sup 28}Si. Resul… more
Date: January 1, 1990
Creator: Fischer, J.; Lissauer, D.; Ludlam, T.; Makowiecki, D.; O'Brien, E.; Radeka, V. et al.
Partner: UNT Libraries Government Documents Department
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Generation of H sup minus , H sub 2 (v double prime ), and H atoms by H sub 2 sup + and H sub 3 sup + ions incident upon barium surfaces

Description: The generation of vibrationally excited molecules by electron excitation collisions and the subsequent generation of negative ions by dissociative attachment to these molecules has become a standard model for volume source operation. These processes have been supplemented recently by the demonstration of atom-surface recombination to form vibrationally excited molecules, and enhanced negative ion formation by protons incident upon barium electrodes. In this paper we consider the additional proc… more
Date: January 1, 1989
Creator: Hiskes, J.R. & Karo, A.M.
Partner: UNT Libraries Government Documents Department
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Experiments and prospects for induction linac drivers

Description: In the last three years, the US program in Heavy Ion Fusion has concentrated on understanding the induction linac approach to a power-plant driver. In this method it is important that the beam current be maximized throughout the accelerator. Consequently, it is crucial to understand the space-charge limit in the AG transport system in the linac and, also, to achieve current amplification during acceleration to keep pace with the kinematical increase of this limit with energy. Experimental resul… more
Date: May 1, 1986
Creator: D., Keefe
Partner: UNT Libraries Government Documents Department
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Ion-beam depth-profiling studies of leached glasses

Description: Ion-beam depth-profiling was carried out on three different glasses leached (or hydrated) in deionized water using /sup 1/H(/sup 19/F,..cap alpha gamma..)/sup 16/O nuclear reaction, secondary ion mass spectrometry (SIMS) and sputter-induced photon spectrometry (SIPS) techniques. The depth-profiles show an interdiffusion mechanism in which the sodium ions in the glass are depleted and replaced by hydrogen (H/sup +/) or hydronium (H/sub 3/O/sup +/) ions from the solution. The leaching behavior do… more
Date: January 1, 1981
Creator: Houser, C. A.; Tsong, I. S. T.; White, W. B.; Wintenberg, A. L.; Miller, P. D. & Moak, C. D.
Partner: UNT Libraries Government Documents Department
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An HVEM study of displacement cascade damage in Nb/sub 3/Sn at 13 K

Description: TEM images of the martensite structure in Nb/sub 3/Sn were recorded at various temperatures between 12 and 30/degree/K. The transition to the superconducting state was observed by a slight deflection of the electron beam due to a perturbation of the magnetic field of the objective lens at the sample. The primary interest is in irradiation effects due to fast neutrons from a fusion reactor, and therefore ion irradiation conditions that are somewhat comparable to this were selected. These consist… more
Date: February 1, 1988
Creator: Kirk, M. A.; Baker, M. C.; Kestel, B. J.; Weber, H. W. & Kampwirth, R. T.
Partner: UNT Libraries Government Documents Department
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Neutralization of H/sup -/ beams with gas jets

Description: A test facility was constructed to create a compact curtain-shaped gas jet as a first-generation operational neutralizer for the 150 keV H/sup -/ beam. Different gases and vapors were considered, their optimum target thicknesses and neutralization efficiencies with respect to beam energies were explored. Two techniques of gas jet formation were compared. Multiparallel-channel effusive jets of CO/sub 2/ and H/sub 2/ were selected as test candidates.
Date: January 1, 1977
Creator: Lam, C. K.
Partner: UNT Libraries Government Documents Department
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Performance of the Los Alamos expanding telescope

Description: An expanding telescope can produce a very low divergence particle beam, provided that the beam optics have sufficient quality in order not to introduce large aberrations. Even as late as two years ago there were no theoretical beamline codes, and little experimental work that could describe the third-order aberrations introduced by an expanding telescope. A project was undertaken at Los Alamos National Laboratory to perform these calculations, and to build a telescope to confirm the predictions… more
Date: January 1, 1988
Creator: Dombeck, T.W.
Partner: UNT Libraries Government Documents Department
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Injection scenarios for TNS

Description: Neutral beam injection heating is the most technically advanced and experimentally proven form of auxiliary Tokamak heating. In TNS, due to its large size and density, the major problem is a lack of beam penetration. An attempt is made to determine the scope of the problem and outline possible strategies for dealing with it. Some of these strategies are: raise the injection energy, injection vertically into a locally produced minimum in the toroidal magnetic field so that the injected ions are … more
Date: January 1, 1977
Creator: Rome, J. A.; Peng, Y. K. M. & Davidson, J. N.
Partner: UNT Libraries Government Documents Department
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Proposal of physics with exotic beams at Oak Ridge

Description: A facility to produce proton-rich radioactive beams for nuclear structure and astrophysics experiments is proposed. This Oak Ridge Exotic Beam (OREB) facility is based on two existing accelerators. Beams of mass up to 80 can be accelerated to energies of about 5 MeV/nucleon. It will provide opportunities to study new areas in nuclear physics and astrophysics that are not available with the use of stable beams. 3 figs.
Date: January 1, 1991
Creator: Lee, I-Yang.
Partner: UNT Libraries Government Documents Department
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Radioactive ion beam research at LLNL

Description: In this paper we discuss efforts underway at LLNL to develop the technology for the measurement of proton and alpha-particle reactions with unstable nuclei which are necessary for understanding the nucleosynthesis and energy generation in hot hydrogen-burning environments. 16 refs., 5 figs.
Date: August 1, 1985
Creator: Mathews, G. J.; Bauer, R. W.; Haight, R. C. & Sale, K. E.
Partner: UNT Libraries Government Documents Department
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Analyzing-power formalism for three-body final states

Description: Various relations important for extraction of analyzing powers from data on reactions involving three particles in the final state were derived. Several of the results pertinent for spin-1/2 and spin-1 polarized beams are presented here. These may be used in analysis of the /sup 1/H(d-vector,pp)n reaction. 3 figures. (RWR)
Date: January 1, 1980
Creator: Ohlsen, G.G.; Brown, R.E.; Correll, F.D. & Hardekopf, R.A.
Partner: UNT Libraries Government Documents Department
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BNL volume H sup minus source

Description: The volume H{sup minus} ion source under development at Brookhaven is unique in that it has a toroidal plasma region, which feeds ions into the central extraction region through a conically shaped filter field. In pulsed operation, it produced 25 mA of H{sup minus} in a 1 cm{sup 2} aperture, with an electron-to-H{sup minus} ratio of {approx} 3. At 19 mA, a normalized, 90% emittance of 0.44 {pi} mm-mrad has been measured. Up to 50 mA has been extracted through a 1.87 cm{sup 2} aperture. Although… more
Date: January 1, 1991
Creator: Prelec, K. & Alessi, J.G.
Partner: UNT Libraries Government Documents Department
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H sup minus temperature dependencies in a Penning surface-plasma source

Description: Simple analysis of the nearly-Maxwellian angular distribution of the ribbon H{sup {minus}} ions beams extracted from a long, narrow slit on the 8X source yields the H{sup {minus}} temperature, kT{sub H{minus}}. The derived kT{sub H{minus}} are 0.1--0.3 eV for a 2-A dc discharge and 0.7-1.3 eV for a 400-A pulsed discharge. Because this diagnostic method relies on simple electronic techniques, it allows rapid study of the dependencies of kT{sub H{minus}} on the source parameters, such as gas flow… more
Date: January 1, 1991
Creator: Smith, H. V. Jr.; Sherman, J. D.; Geisik, C. & Allison, P.
Partner: UNT Libraries Government Documents Department
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Design desiderata for a laminar flow quadrupole-focused acceleration column

Description: The Pierce design acceleration column has been widely used to accelerate high current beams. It operates well in the space charge limited condition, and will produce beams with a temperature comparable with that of the source. It is restricted in current density, however, by the Child-Langmuir relation. If the ion source itself is not the limiting constraint, then the achievable current density is limited by the electric field at which sparking occurs. One sees clearly that the achievable curre… more
Date: January 1, 1983
Creator: Maschke, A.W.
Partner: UNT Libraries Government Documents Department
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Summary from working group on multiple beams and funneling

Description: The working group on Multiple Beams and Funneling discussed various topics related to multiple beams and funneling, including (1) design considerations for multiple-beam accelerators; (2) scaling of current, emittance, and brightness for multiple-beam systems; (3) funneling lines using either discrete components or a radiofrequency quadrupole (RFQ) funneling structure; and (4) alternatives to funneling.
Date: January 1, 1985
Creator: Wangler, T. P.
Partner: UNT Libraries Government Documents Department
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Charged particle fusion targets. [Energy requirements for inertial confinement fusion]

Description: The power, voltage, energy and other requirements of electron and ion beam fusion targets are reviewed. Single shell, multiple shell and magnetically insulated target designs are discussed. Questions of stability are also considered. In particular, it is shown that ion beam targets are stabilized by an energy spread in the ion beam.
Date: November 9, 1977
Creator: Bangerter, R.O. & Meeker, D.J.
Partner: UNT Libraries Government Documents Department
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