Time-implicit fluid/particle hybrid simulations of the anode plasma dynamics in ion diodes

Journal Article · Tue Apr 15 00:00:00 EDT 1997 · AIP Conference Proceedings

DOI:https://doi.org/10.1063/1.53529· OSTI ID:21167514

Pointon, T D; Boine-Frankenheim, O; Mehlhorn, T A ^[1]

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1. Sandia National Laboratories, Albuquerque, New Mexico 87185-1187 (United States)

Applied-B ion diode experiments with Li{sup +1} ion sources on the PBFA II and SABRE ion accelerators show that early in the pulse the beam is essentially pure Li{sup +1}, but is rapidly overwhelmed by impurity ions, called the 'parasitic load'. Furthermore, the increasing parasitic current rapidly drops the diode voltage, limiting the accelerator power that can be coupled into the beam. This 'impedance collapse' is believed to arise from the desorption of impurity neutrals from the anode surface. These neutrals charge-exchange with the ions, rapidly expanding into the anode-cathode gap where they are ionized by beam ions or secondary electrons. In order to model these processes we are developing a 1 1/2 D electrostatic multifluid/PIC (hybrid) code, designed to self-consistently simulate collisional plasma/neutral systems with an arbitrary number of interacting species, over greatly varying density regimes and together with applied electric and magnetic fields.

• OSTI ID: 21167514
• Journal Information: AIP Conference Proceedings, Journal Name: AIP Conference Proceedings Journal Issue: 1 Vol. 406; ISSN 0094-243X; ISSN APCPCS
• Country of Publication: United States
• Language: English

Related Subjects

70 PLASMA PHYSICS AND FUSION TECHNOLOGY
ANODES
CATHODES
CHARGE EXCHANGE
COLLISIONAL PLASMA
COMPUTERIZED SIMULATION
DESORPTION
ELECTRIC CURRENTS
ELECTRIC FIELDS
ELECTRONS
ELECTROSTATICS
FLUIDS
IMPEDANCE
ION SOURCES
LITHIUM IONS
MAGNETIC FIELDS
PARTICLE BEAM FUSION ACCELERATOR
PLASMA DENSITY
PLASMA EXPANSION
PLASMA SIMULATION