Speaker
Description
Commissioning of a Penning Ion Source Test Stand and Negative Hydrogen Ion Experiments for Medical Applications
Authors
R. Gagnon$^{2,4,7}$, C. MacKenzie$^{1,2}$, B. Warfield$^{2,3,5}$, J. Doyle$^{1,2}$, S. Spence$^{2}$, M. Morissette$^{2}$,C. Kent$^{2}$, J. Cramton$^{2}$, C. Drew$^{2}$, J. Taylor$^{2}$, T. Junginger$^{3,5}$, S. Tekumalla$^{4}$, N. Savard$^{7}$,A. George$^{7}$, C. Xiao$^{1}$, M. Bradley$^{1}$,G. Fubiani$^{6}$, L. Couedel$^{1}$, O. Kester$^{5}$, M. Dehnel$^{1,2,3}$.
Affiliations
- University of Saskatchewan — Department of Physics and Engineering Physics
- Selkirk Ion-source Research Center (SIRC)
- University of Victoria — Department of Physics and Astronomy
- University of Victoria — Department of Engineering
- TRIUMF
- LAPLACE, Université de Toulouse, CNRS, Toulouse, France
- D-Pace, Inc.
Abstract
A Penning ion source test stand is currently undergoing commissioning at the Selkirk Ion-source Research Center (SIRC), establishing the infrastructure for a series of graduate research projects. While the source itself, the vacuum box, and the dipole magnet have been donated by D-Pace, the electrical supply, controls, racks and enclosures, gas supply, and deionized water cooling have all been specified, purchased, and assembled by the SIRC team. The source uses a reversible high-voltage supply capable of ±15 kV cathode bias, with the high-voltage platform fully isolated via an isolation transformer and enclosed in a grounded Faraday cage. A programmable logic controller coordinates the arc and magnet supplies, gas delivery, and cooling system. A de-ionized water system rejects heat from the cathode, anode body, and magnet while maintaining the water resistivity needed for operation at high potential. Vacuum testing and leak detection have been performed to improve the seal and allow pump-down into the high-vacuum regime.
Two cathode research programs will be carried out on the commissioned stand. The first applies Laser Powder Bed Fusion (LPBF) additive manufacturing to produce tantalum cathodes, which will be characterized for beam current and lifetime against conventionally machined cathodes. The second builds on a recent D-Pace and Siemens publication that demonstrated a 20% increase in both H¯ extracted from the internal Penning ion source, and H+ ultimately extracted from the cyclotron with a 30% reduction in arc power by embedding small cesium salt cubes into the Penning cathode surface [1]. A SIRC graduate project will develop and characterize cesium-impregnated cathodes in the controlled test stand environment, quantifying improvements in output beam current, arc power consumption, cathode lifetime, and machine safety.
The primary negative ion beam application is injection into medical Positron Emission Tomography (PET) cyclotrons. Near the outer radius of the cyclotron, the ions pass through a stripper foil and become positive ions before striking PET radioisotope production targets to produce radiopharmaceuticals used in medical diagnostics and therapy. This poster presents the status of the Penning source commissioning and cathode experiments completed to date, as well as a description of the planned experimental program.
References
[1] Potkins, D., Dehnel, M., Melanson, S., Stewart, T., Jackle, P., Hinderer, J., Jones, N., & Williams, L. (2018). Improvements to Siemens eclipse PET cyclotron Penning ion source. AIP Conference Proceedings, 2052, 050016.https://doi.org/10.1063/1.5083770
| Email address | cmackenzie0225@gmail.com |
|---|---|
| Funding Agency | Mitacs |
| Classification | Status of facilities |