New Trends in Proton and Carbon Therapy Linacs

In the last years, many developments have contributed to make feasible an all linac solution for proton and carbon ion therapy, with typical output energies of about 200 MeV and 400 MeV/u, respectively. The efficient beam matching of the source to the high-energy linacs, operating at 3 GHz, represents one of the major challenges. With the successful test of a 750 MHz RFQ at CERN, this possibility starts to be a reality. At the same time CERN is testing a high-gradient S-band cavity, successfully exceeding the accelerating gradient goal of 50 MV/m - more than twice what has been obtained before - and paving the way to more compact medical facilities. In this paper, some of the most significant projects involving linear accelerators for hadron therapy will be presented.