Patent ID: 8569717

Claim:
An apparatus configured to control a charged particle beam for irradiation of a tumor of a patient, comprising: a synchrotron configured with an extraction foil, wherein a timing controller times the charged particle beam striking said extraction foil in an acceleration period in said synchrotron resulting in extraction of the charged particle beam at a selected energy; a raster beam scanning system configured to scan the charged particle beam across delivery positions while both (1) delivering the charged particle beam at and between the delivery positions and (2) simultaneously varying said selected energy level of the charged particle beam across the delivery positions, wherein said control of said selected energy further comprises use of readings from a magnetic sensor, said magnetic sensor proximate a bending magnet in said synchrotron; and a feedback system, wherein said feedback system stabilizes a magnetic field in said bending magnet using input from said magnetic sensor to control a correction coil operating at less than ten percent the power of a winding coil, both said correction coil and said winding coil wound around said bending magnet.