Electromagnetic wave propagation in a fast pulse line ion accelerator

Area of Science:

• Particle Accelerators
• Nuclear Physics
• Medical Imaging

Background:

• The pulse line ion accelerator (PLIA) is a cost-effective accelerator concept.
• PLIA was initially designed for heavy ion acceleration.
• Investigating PLIA for light ion acceleration and PET isotope production.

Purpose of the Study:

• Develop a prototype fast PLIA structure.
• Demonstrate electromagnetic wave propagation within the PLIA.
• Assess PLIA's potential for PET isotope production.

Main Methods:

• Constructed a 1.6m fast PLIA structure and a high-voltage pulse generator.
• Utilized capacitive voltage doubling and spark gap switching for pulse generation.
• Measured voltage step-up and wave propagation using resistive and capacitive probes.

Main Results:

• Achieved a voltage step-up of 4.2x and a maximum voltage time-rate-of-change of 0.76 x 10^13 V/s.
• Demonstrated wave propagation with a speed of 1.2 x 10^7 m/s and a half-period of 43 ns.
• Estimated average and peak accelerating gradients of 0.44 and 0.60 MV/m, respectively, without flashover.

Conclusions:

• A multi-stage fast PLIA can serve as a low-cost alternative to cyclotrons for PET isotope production.
• PLIA shows potential for producing isotopes like C-11, N-13, O-15, and F-18.
• Further development could yield accelerating gradients exceeding 1.2 MV/m.