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Characteristics of a RF-Driven Ion Source for a Neutron Generator Used For Associated Particle Imaging

Description: We present recent work on a prototype compact neutron generator for associated particle imaging (API). API uses alpha particles that are produced simultaneously with neutrons in the deuterium-tritium (2D(3T,n)4 alpha) fusion reaction to determine the direction of the neutrons upon exiting the reaction. This method determines the spatial position of each neutron interaction and requires the neutrons to be generated from a small spot in order to achieve high spatial resolution. The ion source for API is designed to produce a focused ion beam with a beam spot diameter of 1-mm or less on the target. We use an axial type neutron generator with a predicted neutron yield of 108 n/s for a 50 muA D/T ion beam current accelerated to 80 kV. The generator utilizes a RF planar spiral antenna at 13.56 MHz to create a highly efficient inductively-coupled plasma at the ion source. Experimental results show that beams with an atomic ion fraction of over 80percent can be obtained while utilizing only 100 watts of RF power in the ion source. A single acceleration gap with a secondary electron suppression electrode is used in the tube. Experimental results, such as the current density, atomic ion fraction, electron temperature, and electron density, from ion source testing will be discussed.
Date: August 8, 2008
Creator: Wu, Ying; Hurley, John P.; Ji, Qing; Kwan, Joe & Leung, Ka-Ngo
Partner: UNT Libraries Government Documents Department

Recent results in the theory of the three-nucleon systems

Description: This paper concentrates on calculational results obtained by the Los Alamos-Iowa Faddeev group and on related calculations. Most of the interest of this group has centered on the Helium 3 and Hydrogen 3 ground states, including the effects of the Coulomb interactions between the two protons in Helium 3. Recent progress in treating the alpha particle is reported and zero energy n-d and p-d scattering and an improved understanding of the scattering lengths for these systems are also discussed. Simple physical pictures for these results are presented where possible. 54 refs., 9 figs. (DWL)
Date: June 1, 1987
Creator: Friar, J.L.
Partner: UNT Libraries Government Documents Department

Zero range three-particle equations. [Karlsson-Zeiger equations]

Description: In order to separate the entire effect of two-particle on-shell scatterings in three-particle systems from the effects of hidden mesonic degrees of freedom (off-shell effects and three-body forces), the zero range limit of the Karlsson-Zeiger equations. Although the Faddeev equations are ambiguous in this limit, the KZ equations remain well defined. Using only two-particle phase shifts, binding energies, and reduced widths, these zero-range equations uniquely predict the three-particle observables which would occur in the absence of hidden mesonic degrees of freedom. The three-particle amplitudes possess all requisite physical symmetry properties, and can be proved to be unitary if the spectator basis is orthonormal and complete. Possible extensions of the scheme for the analysis of three-particle final states, to zero range four-particle equations, and to relativistic systems are conjectured.
Date: April 1, 1978
Creator: Noyes, H.P. & Zeiger, E.M.
Partner: UNT Libraries Government Documents Department

High energy physics at Tufts University. Progress report. [Summaries of research activities at Tufts University]

Description: During the year a final paper was produced on XI* production from 2.9 GeV/c K/sup -/p interactions, and a paper on the ..sigma../sup -/..pi../sup -/..pi../sup +/ (..pi../sup 0/) final state from 2.9 GeV/c K/sup -/d interactions is on the verge of completion. From our 14.75 GeV/c anti pp experiment results have been prepared for publication on three topics: the charm search, V/sup 0/ inclusive production, and ..pi../sup 0/ production. Further analysis of data is continuing. In the 300 GeV/c pp experiment, investigations are completed or underway in three areas: neutral and charged pion correlations, inclusive ..gamma.. and V/sup 0/ production, and inclusive resonance production. Further data on inclusive V/sup 0/ distributions from 6.5 GeV/c K/sup -/p interactions has been obtained and analysis is nearing completion. A good deal of effort went into the development of proposals for new physics. These new directions may be represented by three approved experiments at three different laboratories: Neutrino-deuterium interactions at Fermilab (an approved and a proposed experiment); Search for new states decaying into anti ..lambda lambda.. and K/sup 0//sub s/K/sup 0//sub s/ using the Multiparticle Spectrometer at B.N.L. (approved in May, 1977); Search for baryonium using the SLAC hybrid bubble chamber system, which won approval in September with a recommendation for prompt running from the Program Advisory Committee. A list of publications is included.
Date: September 1, 1977
Partner: UNT Libraries Government Documents Department

nD scattering at 180/sup 0/ for neutron energies from 200 to 800 MeV. [Preliminary results, differential cross sections, 200 to 800 MeV]

Description: In the expectation that information on the high momentum components of the deuteron wave function can be obtained from the scattering of hadrons of modest energy, the 180/sup 0/ excitation function is reported which was measured in nd elastic scattering for incident energies of 200 to 800 MeV. Differential cross sections are plotted. However, only a small fraction of the data are analyzed thus far. 17 references. (JFP)
Date: January 1, 1977
Creator: Bonner, B. E.; Hollas, C. L.; Newsom, C. R.; Riley, P. J. & Glass, G.
Partner: UNT Libraries Government Documents Department