Title :
Electrical diagnostics of the magnetically confined anode plasma source
Author :
Crawford, M.T. ; Johnson, D.J. ; Maenchen, J.E.
Author_Institution :
Sandia Nat. Labs., Albuquerque, NM, USA
Abstract :
Summary form only given. The Magnetically confined Anode Plasma (MAP) ion diode is designed to provide intense, repetitive, high-purity ion beams for materials processing. The MAP diode can provide tens of kiloamps of ion beam current at >500 kV acceleration potentials. Previous models have been operated at up to 100 Hz in a burst mode. The source of the ions is a magnetically confined plasma which is generated by ionizing a puff of neutral gas. The ionization of the gas is performed by induced electric fields from a fast rising (/spl sim/2 /spl mu/s) magnetic field pulse. This magnetic field is also used to move the plasma into proper position for extraction by the accelerator voltage pulse. Plasma diagnostics have been performed primarily with bare-wire El-dot probes, Langmuir probes and time-integrated and time-resolved photography. Neutral gas measurements were made with very sensitive piezo-resistive (PZR) pressure transducers and fast ionization gauge (FIG) tubes. Differential B-dot pair arrays were employed to determine the magnetic fields generated by the fast coil and to note the change in those magnetic fields due to the plasma formation and motion. Langmuir probe data, used in conjunction with the B-dots to determine arrival times of the plasma, are presented as well.
Keywords :
plasma production; 100 Hz; 2 mus; 500 kV; Langmuir probes; acceleration potentials; accelerator voltage pulse; bare-wire El-dot probes; burst mode; differential B-dot pair arrays; electrical diagnostics; fast ionization gauge tubes; induced electric fields; intense repetitive high-purity ion beams; ion beam current; ion diode; magnetic field pulse; magnetically confined anode plasma source; magnetically confined plasma; materials processing; neutral gas; neutral gas measurements; piezo-resistive pressure transducers; plasma diagnostics; time-integrated photography; time-resolved photography; Anodes; Magnetic confinement; Magnetic field measurement; Plasma accelerators; Plasma confinement; Plasma diagnostics; Plasma materials processing; Plasma measurements; Plasma sources; Probes;
Conference_Titel :
Plasma Science, 1996. IEEE Conference Record - Abstracts., 1996 IEEE International Conference on
Conference_Location :
Boston, MA, USA
Print_ISBN :
0-7803-3322-5
DOI :
10.1109/PLASMA.1996.550843