The magnets and power supplies of the GSI beam scanning system for heavy ion cancer therapy

The magnets and power supplies of a raster scanning system for a particle therapy facility have been designed and carefully measured after delivery. Well known and proven techniques have been used in construction and production of the laminated window frame magnets and the pulsed power supplies to avoid failures of the system and to assure absolute security of patients during treatment. The scanning interval in both transverse directions is 20 cm. The vertical deflection includes an offset of 20 cm between the undeflected beam and the scanning area to have space for last beam diagnostic purposes just before beginning treatment. The scanning depth is established by varying the energy of the carbon, oxygen, or neon ions to energies up to 550 A MeV.