摘要:
An electromagnetic wave generating device includes: a hollow annular vacuum chamber; an electron gun; an electromagnet configured with a pair of discoid combinations in which a cylindrical accelerating magnet pole and an annular focusing magnet pole are arranged in this order from the inner side to the outer side of the combinations, and are disposed symmetrically and concentrically with each other on both sides of the chamber and coaxially with the center axis of the chamber, and a return yoke disposed outside both accelerating and focusing magnet poles and the chamber; accelerating coils wound around the accelerating magnet poles, for exciting the poles; and focusing coils wound around the focusing magnet poles, for exciting the poles; wherein a through hole is formed at the center of the accelerating magnet pole so that power supply wires connecting the accelerating coils to an accelerating power supply are led out through the hole.
摘要:
An electromagnetic wave generating device includes: a hollow annular vacuum chamber; an electron gun; an electromagnet configured with a pair of discoid combinations in which a cylindrical accelerating magnet pole and an annular focusing magnet pole are arranged in this order from the inner side to the outer side of the combinations, and are disposed symmetrically and concentrically with each other on both sides of the chamber and coaxially with the center axis of the chamber, and a return yoke disposed outside both accelerating and focusing magnet poles and the chamber; accelerating coils wound around the accelerating magnet poles, for exciting the poles; and focusing coils wound around the focusing magnet poles, for exciting the poles; wherein a through hole is formed at the center of the accelerating magnet pole so that power supply wires connecting the accelerating coils to an accelerating power supply are led out through the hole.
摘要:
In a particle beam therapy system which scans a particle beam and irradiates the particle beam to an irradiation position of an irradiation subject and has a dose monitoring device for measuring a dose of the particle beam and an ionization chamber smaller than the dose monitoring device, the ionization chamber measuring a dose of a particle beam passing through the dose monitoring device, the dose of the particle beam irradiated by the dose monitoring device is measured; the dose of the particle beam passing through the dose monitoring device is measured by the small ionization chamber; and a correction coefficient of the dose measured by the dose monitoring device corresponding to the irradiation position is found based on the dose of the particle beam measured by the small ionization chamber.
摘要:
A magnetic resonance imaging method and apparatus for obtaining images of slices of a body placed in a static magnetic field. During the sampling of one NMR signal, an additional second gradient magnetic field is impressed on the body to acquire data. These data are additionally sampled during each sampling. This enables the number of data to be increased and the number of repetitions to be reduced, thereby accomplishing a Fourier transformation at a higher speed.
摘要:
A particle beam irradiation apparatus according to the present invention is provided with a vacuum duct that forms a vacuum region through which the charged particle beam passes, a vacuum window through which the charged particle beam is launched from the vacuum region, a scanning electromagnet that scans the charged particle beam; a monitoring apparatus including a position monitor that detects the passing position of a charged particle beam and the beam size thereof, a low-scattering gas filling chamber including the monitoring apparatus, and an irradiation management apparatus that controls irradiation of the charged particle beam; the particle beam irradiation apparatus is characterized in that the low-scattering gas filling chamber is changeably disposed in such a manner that the beam-axis-direction positional relationship between the monitoring apparatus and the vacuum window is a desired one and in that the low-scattering gas filling chamber is filled with a low-scattering gas.
摘要:
A particle beam therapy system comprising a treatment table, a treatment table control unit and an irradiation control unit configured to output an instruction for controlling the treatment table control unit, an accelerator and a scanning electromagnet, wherein after the treatment table control unit controls the treatment table so as for a patient isocenter which is reference position of an affected area of a patient to move to a position of an irradiation isocenter which is set at a position which is closer to an irradiation nozzle than an equipment isocenter which is reference of positional relation of the irradiation nozzle and the treatment table, the irradiation control unit outputs an instruction for irradiating the patient with a particle beam.
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:
A method of manufacturing a radio frequency accelerator that accelerates charged particles injected into a second-stage linear accelerator from a first-stage linear accelerator includes a step of setting a value of a power distribution factor R for the power distributor to supply radio frequency power to the second-stage linear accelerator and a value of a ratio L/ω of a length L of the matching section between the outlet of the first-stage linear accelerator and the inlet of the second-stage linear accelerator to the angular frequency ω of the radio frequency power, so that a charged particle beam is extracted from the second-stage linear accelerator over a range of the total radio frequency power wider than a widest allowable range among allowable total radio frequency power ranges determined for each phase of charged particles on the basis of phase acceptance of the second-stage accelerator.
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 objective is to obtain a particle beam therapy system that can suppress the effect of a leakage dose. There are provided a scanning nozzle that irradiates in a predetermined direction a particle beam emitted from an accelerator; an irradiation control unit that controls operation of the irradiation nozzle in such a way that the particle beam of a predetermined dose is sequentially irradiated onto each of a plurality of spots set in a planar direction in an irradiation subject; and a control unit that on/off-controls emission of the particle beam from the accelerator. The irradiation control unit makes the irradiation nozzle scan in a diluting manner the particle beam onto a predetermined area in the irradiation subject, in a predetermined period after a time point when emission is switched from ON to OFF, or in a period from the time point when emission is switched from ON to OFF to a time point when the particle beam is cut off.