Multiple energy extraction experiment at XiPAF synchrotron

Abstract

Multiple energy extraction is a technology in the field of slow extraction from synchrotrons. This technology provides multiple flattops with different beam energies used for extraction in a single synchrotron cycle. Particle beams with different energies can be extracted in one cycle, which reduces the time for beam energy change in hadron therapy. In this paper, a new scheme for multiple energy extraction is proposed. In the new scheme, the stable phase space region shrinks slightly for each energy flattop, and the shrinkage factor of the stable region is the same for different energy flattops. The new scheme can effectively reduce the spill intensity overshoot while avoiding a reduction in the extraction efficiency in the process of multiple energy extraction. A proof-of-principle experiment was conducted at the Xi’an 200 MeV Proton Application Facility (XiPAF) synchrotron. The experimental results were in agreement with the theoretical expectations. This demonstrates the advantages of the new scheme.