Patent ID: 7423278

Claim:
Acceleration system for composite charged particles, nuclear or molecular, with mass number greater than 1, in the form of ion beams, comprising: a conventional or superconducting cyclotron, a radiofrequency linear accelerator (Linac), a medium energy beam transport line (MEBT) connected, on one end, either to the cyclotron output or to the output of the first part of the radiofrequency linear accelerator and, on the other end, either to the input of the radiofrequency linear accelerator or to the second part of the said radiofrequency linear accelerator, and a high energy beam transport line (HEBT) connected, on one end to the output of said radiofrequency linear accelerator and on the other end to a system for dose distribution to the patient, wherein, the radiofrequency linear accelerator features a resonant frequency greater than or equal to 1 GHz, and in order to accelerate 12 C 6+ carbon ions starting at 300 MeV/u the section CCL alone of said Linac is used with frequencies of 2.998 GHz or 5.710 GHz and for which are included the following parameters respectively: Frequency [MHz] 2998 5710 Q (ion charge) 6 6 A (ion mass) 12 12 Input Energy [MeV] 3600 3600 Output Energy [MeV] 4800 4800 Number of accelerating cells per accelerating 20 13 structure Accelerating cell diameter [mm] 70 40 Beam hole aperture diameter [mm] 8 4 Number of accelerating structures per module 2 2 Number of modules (same as the number of klystrons) 10 16 Average length of a module [m] 1.8 0.72 Total length of the Linac [m] 17.8 11.5 Average transit time factor T 0.86 0.89 Average effective shunt impedance ZT 2 [MΩ/m] 79 91 Average electric field on axis E 0 [MV/m] 17.8 31 Maximum surface electric field in Kilpatrick units 1.7 2.2 Average peak power required per module [MW] 4.4 4.2 Average power per module [kW] 4.4 4.2 Average power of the Linac [kW] 44 67.2 Duty Factor [%] 0.1 0.1 Synchronous phase φ s [degrees] −15 −15 Magnetic quadrupole length [mm] 52 60 Magnetic quadrupole aperture diameter [mm] 10 5 Average quadrupole magnetic gradient B′ [T/m] 160 320 (in FODO configuration) Normalized transverse acceptance, 1 rms [π mm mrad] 1.8 1.4.