Abstract:
PURPOSE:The pulse line ion accelerator (PLIA) is a low-cost accelerator concept originally designed to accelerate heavy ions. Our group has been investigating the use of PLIA to accelerate light ions and believe a multi-stage PLIA could be useful for short half-life PET isotope production. The goal of this work was to develop a single prototype fast PLIA structure and demonstrate electromagnetic wave propagation using a high-voltage pulser. MATERIALS AND METHODS:A 1.6 m fast PLIA structure (wave speed > 107 m/s) was constructed along with a high-voltage, sinusoidal pulse generator. The latter uses capacitive voltage doubling and spark gap switching. A step-up transformer couples voltage from the pulser to the PLIA coil. Voltage measurements on the coil were made in air using a high-voltage resistive probe, while capacitive probes placed along the length of the PLIA were used to measure wave propagation with the PLIA structure filled with transformer oil. RESULTS:Voltage measurements acquired on the primary and secondary coils of the transformer coupler in air demonstrated a peak-to-peak voltage step-up of 4.2 relative to the pulser DC charging voltage. The maximum voltage time-rate-of-change on the PLIA coil was 0.76 × 1013 V/s. Capacitive probe measurements indicated voltage oscillations on the PLIA coil with half-period equal to 43 ± 0.9 ns and wave speed (with oil) of 1.2 × 107 m/s. Average and peak accelerating gradients were conservatively estimated to be 0.44 and 0.60 MV/m, respectively, with a charging voltage of 55 kV. Wave propagation was demonstrated at these gradients without flashover at a vacuum pressure of 9 × 10-6 Torr. Submerging the pulser in oil would allow for charging voltages up to 150 kV and produce accelerating gradients >1.2 MV/m. CONCLUSIONS:Use of a multi-stage, fast PLIA for light ion acceleration could provide a low-cost complement to cyclotrons for the production of short half-life isotopes used for PET imaging, including carbon-11, nitrogen-13, oxygen-15, and fluorine-18.
journal_name
Med Physjournal_title
Medical physicsauthors
Behbahani RA,Diot Q,Kavanagh B,Serkova NJ,Miften M,Westerly DCdoi
10.1002/mp.13875subject
Has Abstractpub_date
2019-12-01 00:00:00pages
5714-5721issue
12eissn
0094-2405issn
2473-4209journal_volume
46pub_type
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