Electromagnetic Characterization of Big Aperture Magnet Used in Particle Beam Cancer Treatment

J. Osorio Moreno[1], M. Pullia[1], C. Priano[1]
[1]Fondazione CNAO, Pavia, Italy

Resistive magnets are one of the principal components of ion medical accelerator systems used in heavy ion cancer treatment. To fulfill medical requirements, like the size of irradiation field and an uniform dose distribution, some magnets of the transport beam line may require large aperture and a large region where the magnetic field is within specifications (good field region). After a validation benchmark between COMSOL simulations and measurements of a dipole magnet used in the CNAO facility, COMSOL Multiphysics has been used to characterize the magnetic field quality of a very large 90° bending magnet. A stiffening frame has then been foreseen to preserve the mechanical rigidity of the magnet and its impact on the field quality has been investigated.