Time-resolved proton focus of a high-power ion diode

Journal Article · Mon Jul 01 04:00:00 EDT 1985 · J. Appl. Phys.; (United States)

DOI:https://doi.org/10.1063/1.335697· OSTI ID:5665440

Johnson, D J; Leeper, R J; Stygar, W A; Coats, R S; Mehlhorn, T A; Quintenz, J P; Slutz, S A; Sweeney, M A

An improved understanding of the factors that control the axial focus of applied-B ion diodes was obtained from time-resolved diagnostics of ion-beam trajectories. This resulted in a new selection of anode shape that produced a proton focus of 1.3-mm diameter from a 4.5-cm-radius diode, which is a factor of 2 improvement over previous results. We have achieved a peak proton power density of 1.5 +- 0.2 TW/cm/sup 2/ on the 1-TW Proto I accelerator. The radial convergence of this proton beam, defined as the ratio of the anode diameter to focused beam FWHM, is 70. Time-resolved information about virtual cathode evolution, the self- and applied-magnetic-field bending, and the horizontal focus of the beam was also obtained. In addition, the diffusion of the magnetic field into the anode plasma is estimated by measuring the horizontal focal position as a function of time. Finally, we discuss the effects of gas cell scattering on the beam focus.

• Research Organization: Sandia National Laboratories, Albuquerque, New Mexico 87185
• DOE Contract Number: AC04-76DP00789
• OSTI ID: 5665440
• Journal Information: J. Appl. Phys.; (United States), Journal Name: J. Appl. Phys.; (United States) Vol. 58:1; ISSN JAPIA
• Country of Publication: United States
• Language: English

Related Subjects

70 PLASMA PHYSICS AND FUSION TECHNOLOGY
700104* -- Fusion Energy-- Plasma Research-- Plasma Kinetics-Experimental-- (-1987)
700106 -- Fusion Energy-- Plasma Research-- Plasma Production-- (-1987)
ANODES
BEAM DYNAMICS
BEAM OPTICS
BEAMS
CAMERAS
DIODE TUBES
ELECTRODES
ELECTRON TUBES
FOCUSING
ION BEAMS
NUCLEON BEAMS
PARTICLE BEAMS
PLASMA DIAGNOSTICS
PROTON BEAMS
THERMIONIC DIODES
THERMIONIC TUBES
TRAJECTORIES