Particle therapy system

摘要

A particle therapy system capable of confirming energy of an accelerated charged particle beam before the charged particle beam is irradiated to an irradiation target. A beam position monitor is disposed in a synchrotron, and a cavity voltage monitor is associated with an RF cavity for acceleration. An ion beam orbiting within the synchrotron is accelerated with application of an RF voltage applied to the RF cavity and is extracted from the synchrotron with application of an RF voltage applied to an RF knockout electrode. Based on a cavity voltage signal detected by the cavity voltage monitor, a frequency counter measures the frequency of the RF voltage applied to the RF cavity. Based on a voltage detected by the beam position monitor, a beam signal processing unit measures the position of a beam orbit. Based on the frequency of the RF voltage and the position of the beam orbit, the energy judgment processing unit determines whether energy of the ion beam after the end of the acceleration is normal or abnormal.