Cleaning techniques for applied-B ion diodes

Conference · Fri Sep 01 04:00:00 EDT 1995

OSTI ID:112933

Cuneo, M E; Menge, P R; Hanson, D L ^[1]

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1. and others

Measurements and theoretical considerations indicate that the lithium-fluoride (LiF) lithium ion source operates by electron-assisted field-desorption, and provides a pure lithium beam for 10--20 ns. Evidence on both the SABRE (1 TW) and PBFA-II (20 TW) accelerators indicates that the lithium beam is replaced by a beam of protons, and carbon resulting from electron thermal desorption of hydrocarbon surface and bulk contamination with subsequent avalanche ionization. Appearance of contaminant ions in the beam is accompanied by rapid impedance collapse, possibly resulting from loss of magnetic insulation in the rapidly expanding and ionizing, neutral layer. Electrode surface and source substrate cleaning techniques are being developed on the SABRE accelerator to reduce beam contamination, plasma formation, and impedance collapse. We have increased lithium current density a factor of 3 and lithium energy a factor of 5 through a combination of in-situ surface and substrate coatings, impermeable substrate coatings, and field profile modifications.

• Research Organization: Sandia National Labs., Albuquerque, NM (United States)
• Sponsoring Organization: USDOE, Washington, DC (United States)
• DOE Contract Number: AC04-94AL85000
• OSTI ID: 112933
• Report Number(s): SAND--94-3136C; CONF-950750--38; ON: DE95017882
• Country of Publication: United States
• Language: English

Related Subjects

43 PARTICLE ACCELERATORS
70 PLASMA PHYSICS AND FUSION TECHNOLOGY
ACCELERATORS
CLEANING
CONTAMINATION
ELECTRODES
INERTIAL CONFINEMENT
ION BEAMS
SUBSTRATES
SURFACES