High Gradient Accelerating Structure for Low Energy Protons

Proton and carbon radiotherapy systems demonstrated significant advantages in clinical efficiency and reduced toxicity profiles for many types of cancers, however the high cost of equipment and facilities are presently the limiting factor preventing hadron therapy from becoming the standard of care for a wider range of patients. Developing a linear accelerator capable of multiplexing carbon and proton beams would offer a promising approach to simultaneously reduce the cost and improve the quality of the treatment. In response to this problem, RadiaBeam Systems in collaboration with Argonne National Laboratory has designed a novel S-band accelerating structure for protons or carbon ions, operating at the first negative spatial harmonic and capable of providing >50 MV/m gradient. In Phase I, we have done the electromagnetic design and optimization of 15-cell negative harmonic structure, and verified the feasibility of this novel approach with 3D beam dynamics simulations. We have performed the conceptual engineering design and manufacturing studies required to build the section, and performed transient thermo-structural analysis to validate the feasibility of structure operation in high gradient pulsed regime at the required repetition rate. In Phase II, RadiaBeam will perform full engineering design of the structure, including cooling, tuning and support elements. Afterwards, the structure will be fabricated, brazed and tuned, and delivered to Argonne National Laboratory for high power tests. The success of this project will be a major milestone towards demonstrating the technical feasibility of the entire carbon-proton linac radiotherapy system. This represents an attractive commercial opportunity in the aggressively growing market segment of hadron radiotherapy. In addition, the success of this project will result in improved availability and affordability of highly- promising ion radiation therapy for a wider range of cancer patients. In this project, an enabling technology for the new heavy particles radiotherapy system will be developed. The successful implementation of such system will save lives, and improve the patients’ quality of live, while reducing the costs compare to radiotherapy systems presently in operation.