Resource Type

High energy negative deuterium beams using double charge-exchange or surface production (open access)

High energy negative deuterium beams using double charge-exchange or surface production

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.
System: The UNT Digital Library
Negative-ion-based neutral beams and upgraded fusion devices (TFTR, MFTF) (open access)

Negative-ion-based neutral beams and upgraded fusion devices (TFTR, MFTF)

The development of negative-ion-based (H/sup -/, D/sup -/) neutral beams for TFTR and MFTF is discussed. Problems with existing equipment include providing beam current and current density, voltage holding, and gas pumping. The problem of stripping the D/sup -/ is described; it is concluded that photodetachment would be desirable to prevent formation of high-energy D/sup +/. Estimates of the parameters associated with photodetachment show it may be feasible although a detailed study will be required.
Date: November 29, 1977
Creator: Hooper, E. B. Jr. & Fink, J. H.
System: The UNT Digital Library
Sputtering calculations with the discrete ordinated method (open access)

Sputtering calculations with the discrete ordinated method

The purpose of this work is to investigate the applicability of the discrete ordinates (S/sub N/) method to light ion sputtering problems. In particular, the neutral particle discrete ordinates computer code, ANISN, was used to calculate sputtering yields. No modifications to this code were necessary to treat charged particle transport. However, a cross section processing code was written for the generation of multigroup cross sections; these cross sections include a modification to the total macroscopic cross section to account for electronic interactions and small-scattering-angle elastic interactions. The discrete ordinates approach enables calculation of the sputtering yield as functions of incident energy and angle and of many related quantities such as ion reflection coefficients, angular and energy distributions of sputtering particles, the behavior of beams penetrating thin foils, etc. The results of several sputtering problems as calculated with ANISN are presented.
Date: November 29, 1977
Creator: Hoffman, T. J.; Dodds Jr., H. L.; Robinson, M.T. & Holmes, D.K.
System: The UNT Digital Library