Particle therapy gantry with an energy degrader and an achromatic final bending system

Abstract

A movable gantry for delivery of a particle beam using beam scanning technique contains an inlet section for an accelerated particle beam having quadrupole magnets, first and second bending sections having dipole and quadrupole magnets for beam correction, a transfer section having quadrupole magnets for beam correction and a degrader and a last beam bending section having separate and/or combined dipole/quadrupole/higher order multipole magnets forming an achromatic section. All the magnets of the achromatic last bending section are located downstream of the degrader. Any dispersion in this achromatic last bending section is suppressed. A scanning section having two separate or one combined fast deflection magnets that deflect the beam at the iso-center in a direction perpendicular to the beam direction to perform lateral scanning is provided. A beam nozzle section is provided and has a beam nozzle.