A compact low energy proton source.

Area of Science:

• Plasma Physics
• Particle Accelerators
• Ion Sources

Background:

• Non-neutral plasma experiments require pure, low-energy ion beams.
• Existing ion sources often suffer from significant molecular ion contamination.
• Controlling ion species and energy is crucial for precise experimental control.

Purpose of the Study:

• To develop and characterize a novel low-energy proton source for non-neutral plasma research.
• To achieve high proton purity by suppressing molecular hydrogen ions (H2+ and H3+).
• To enable tunable proton beam energies for versatile experimental applications.

Main Methods:

• Utilized a geometrically compensated Penning trap with a hot filament electron source.
• Employed dissociative ionization of H2 gas to generate protons.
• Applied a rotating wall electric field to stabilize protons and destabilize molecular ions.
• Measured ion species purity and beam energy using diagnostic tools.

Main Results:

• Successfully generated proton bunches with low molecular ion contamination (5.5% H2+, 15.5% H3+).
• Demonstrated tunability of proton beam energy from 35 eV to 300 eV.
• The rotating wall field effectively concentrated protons and reduced unwanted ion species.

Conclusions:

• The developed proton source is effective for non-neutral plasma experiments requiring pure proton beams.
• The method of using a rotating wall electric field is a viable technique for ion species control in Penning traps.
• The tunable energy range makes this source suitable for a variety of plasma physics investigations.