Magnetically focused 70 MeV proton minibeams for preclinical experiments combining a tandem accelerator and a 3 GHz linear post‐accelerator

Purpose Radiotherapy plays an important role for the treatment of tumor diseases in two-thirds all cases, but it is limited by side effects surrounding healthy tissue. Proton minibeam radiotherapy (pMBRT) a promising option to widen therapeutic window control at reduced effects. An accelerator concept based on existing tandem Van de Graaff and linac enables focusing 70 MeV protons form minibeams with size only 0.1 mm preclinical small animal irradiation facility, while avoiding cost RFQ injector. Methods The provides 16 proton beam brightness as averaged from 5 µs long pulses flat top current 17 µA 200 Hz repetition rate. Subsequently, are accelerated 3 GHz linear post-accelerator consisting two Side Coupled Drift Tube Linac (SCDTL) structures four Cavity (CCL) [design: AVO-ADAM S.A (Geneva, Switzerland)]. A buncher magnetic quadrupole lenses placed between maximize transmission through linac. triplet situated downstream structure focuses into area (0.1 × 0.1) mm2. dynamics facility optimized using particle optics code TRACE three-dimensional (3D). elaborated tracking TRAVEL. Results study about amplitude phase shift showing that 49% available can be transported post-accelerator. mean up 19 nA expected within mm2 focus. Conclusion extension accelerators commercially able deliver serves requirements obtain perform irradiations would case complete commercial injector-RFQ–linac combination. Due modularity structure, extended clinically relevant energies or above MeV.