摘要:
A circular accelerator comprises a target current value memory which stores a target current value of a beam current of charged particle which is extracted from an extracting device; and a frequency determination part in which a frequency change ratio is obtained by performing a feedback control based on an error signal between a detection signal of a beam current detector and a target current value which is stored in a target current value memory, and determines a subsequent frequency from the obtained frequency change ratio and a current frequency, wherein the subsequent frequency which is determined by the frequency determination part is stored in a frequency memory and a radio-frequency generator generates the subsequent radio-frequency of frequency which is determined.
摘要:
A circular accelerator comprises a target current value memory which stores a target current value of a beam current of charged particle which is extracted from an extracting device; and a frequency determination part in which a frequency change ratio is obtained by performing a feedback control based on an error signal between a detection signal of a beam current detector and a target current value which is stored in a target current value memory, and determines a subsequent frequency from the obtained frequency change ratio and a current frequency, wherein the subsequent frequency which is determined by the frequency determination part is stored in a frequency memory and a radio-frequency generator generates the subsequent radio-frequency of frequency which is determined.
摘要:
A septum magnet includes a yoke that can be separated at the approximately center portion thereof in the axis direction; a septum coil; a return coil; and a vacuum duct that is inserted between the septum coil and the return coil. The septum coil is formed in such a way as to be able to be separated into a first portion and a second portion in response to separation of the yoke; and in a space between the septum coil and the vacuum duct, there is provided an auxiliary coil, in two portions of which, corresponding to the first portion and the second portion of the septum coil, electric currents flow in opposite direction to each other in a circumferential direction.
摘要:
A septum magnet includes a yoke that can be separated at the approximately center portion thereof in the axis direction; a septum coil; a return coil; and a vacuum duct that is inserted between the septum coil and the return coil. The septum coil is formed in such a way as to be able to be separated into a first portion and a second portion in response to separation of the yoke; and in a space between the septum coil and the vacuum duct, there is provided an auxiliary coil, in two portions of which, corresponding to the first portion and the second portion of the septum coil, electric currents flow in opposite direction to each other in a circumferential direction.
摘要:
A charged particle beam transport system is characterized in that in a fixed transport unit, a phase of a phase space distribution of a charged particle beam at an inlet of a rotating deflection unit that rotates around an gantry rotation axle of a rotating gantry coincides with a phase determined by a calculation based on an average value of a first phase advance and a second phase advance. The first phase advance is defined as a change in a phase, of the phase space distribution, that changes when the charged particle beam travels from the inlet of the rotating deflection unit to an isocenter in the case where a gantry angle is a gantry reference angle; the second phase advance is defined as a change in a phase at a time when the gantry angle is pivoted by 90° from the gantry reference angle.
摘要:
A charged particle beam transport system is characterized in that in a fixed transport unit, a phase of a phase space distribution of a charged particle beam at an inlet of a rotating deflection unit that rotates around an gantry rotation axle of a rotating gantry coincides with a phase determined by a calculation based on an average value of a first phase advance and a second phase advance. The first phase advance is defined as a change in a phase, of the phase space distribution, that changes when the charged particle beam travels from the inlet of the rotating deflection unit to an isocenter in the case where a gantry angle is a gantry reference angle; the second phase advance is defined as a change in a phase at a time when the gantry angle is pivoted by 90° from the gantry reference angle.
摘要:
The present invention is intended to enable proper elimination of the remanent magnetization of the scanning magnet, which is used in a particle beam therapy system, in a short time. In the particle beam therapy system that irradiates an irradiation target with a particle beam 18 accelerated by an accelerator and scanned by scanning magnets 11 and 12, power supplies 13 and 14 to operate the scanning magnets 11 and 12 output pattern currents for demagnetizing the scanning magnets 11 and 12. The pattern current is controlled by a control circuit 15 that reads a demagnetization pattern 17 and controls the power supplies 13 and 14.
摘要:
In gantry type particle beam irradiation system comprising a gantry and being configured to irradiate a particle beam, which has small emittance in X direction and large emittance in Y direction at an extraction position of a circular accelerator, from an irradiation nozzle installed in the gantry to an irradiation target, the irradiation nozzle has a ridge filter which is installed so as for a direction in which emittance in X direction is maintained to tilt to a direction which is perpendicular to a ridge of the ridge filter by a predetermined angle in the state where the gantry is a reference angle.
摘要:
The object is to effectively reduce the resonant current flowing inside a converter unit and an inverter unit in a power conversion apparatus for an electric vehicle. The power conversion apparatus includes a converter unit that converts an alternating-current power into a direct-current power, an inverter unit that converts the direct-current power into an intended alternating-current power and supplies the intended alternating-current power to an electric motor that drives an electric vehicle, a housing that accommodates the converter unit and the inverter unit and a part of which is connected to ground, and a magnetic core that is disposed inside the housing and that suppresses the resonant current flowing between the converter unit and the inverter unit.
摘要:
The object is to effectively reduce the resonant current flowing inside a converter unit and an inverter unit in a power conversion apparatus for an electric vehicle. The power conversion apparatus includes a converter unit that converts an alternating-current power into a direct-current power, an inverter unit that converts the direct-current power into an intended alternating-current power and supplies the intended alternating-current power to an electric motor that drives an electric vehicle, a housing that accommodates the converter unit and the inverter unit and a part of which is connected to ground, and a magnetic core that is disposed inside the housing and that suppresses the resonant current flowing between the converter unit and the inverter unit.