Speaker
Description
Acceleration of mixed beams with unequal A/Q, or dual-frequency acceleration, constitutes an interesting option to enlarge the possible combinations of ions delivered simultaneously from a synchrotron, with potential applications in particle therapy, plasma physics, nuclear physics, and materials research. In this scheme, two ion beams are injected sequentially using multi-turn injection and then independently captured and accelerated in the same magnetic fields at their respective revolution frequency by applying an individual RF program per beam. Recently, the feasibility of dual-frequency accelerations has been demonstrated at the GSI synchrotron SIS18 with low intensities of 56Fe25+ and 209Bi68+. In this contribution, we first give some general requirements and limitations for dual-frequency acceleration. Then, we report on results from the proof-of-principle experiment regarding the influence of the RF program for the second ion beam on the first ion beam and identify the physical origin of observed effects. Finally, we discuss the need for more systematic investigations to confirm our inferences and to study the beam-beam effects expected at higher intensities.