Development of cold cathode arc discharge filament based multi-cusp H^- ion source

Area of Science:

• Plasma physics
• Ion source technology
• Accelerator physics

Background:

• Development of efficient and long-lasting ion sources is crucial for various applications.
• Traditional H- ion sources often rely on cesium, posing operational and maintenance challenges.
• Cold cathode discharges offer a promising alternative for cesium-free operation.

Purpose of the Study:

• To develop and characterize a novel cold cathode arc discharge multicusp H- ion source (HNIS).
• To investigate an innovative low-power igniter system for enhanced filament lifetime.
• To evaluate the performance of the cesium-free HNIS and its steering magnetic field for electron separation.

Main Methods:

• Utilized a cold cathode arc discharge filament within a multicusp configuration.
• Implemented a low-power igniter system operating in a glow discharge regime.
• Employed a triode extraction system and a steering magnetic field for beam extraction and electron suppression.
• Conducted experimental commissioning and 3-D ion beam simulations.

Main Results:

• Achieved a maximum H- ion beam current of 12 mA at 50 keV beam energy in pulse mode.
• Demonstrated a longer filament lifetime due to the innovative igniter system.
• Successfully separated co-extracted electrons from the H- ion beam using the steering magnetic field.
• Validated experimental results with 3-D ion beam simulations.

Conclusions:

• The developed cold cathode multicusp HNIS is a promising cesium-free alternative for generating high-current H- ion beams.
• The innovative igniter system significantly improves filament longevity.
• The steering magnetic field effectively manages electron co-extraction, crucial for beam quality.