Pulsed RF knock-out extraction: a potential enabler for FLASH hadrontherapy in the Bragg peak.

One challenge on the path to delivering FLASH-compatible beams with a synchrotron is facilitating an accurate dose control for the required ultra-high dose rates. We propose the use of pulsed RFKO extraction instead of continuous beam delivery as a way to control the dose delivered per Voxel. In a first feasibility test, dose rates in pulses of up to 600 Gy s-1were observed, while the granularity at which the dose was delivered is expected to be well below 0.5 Gy.