Mitsubishi Electric Corporation

Hitachi, Ltd.

Shuhei Odawara

Kengo Sugahara

Kazushi Hanakawa

Katsuhisa Yoshida

Masahiro Ikeda

Hisashi Harada

Taizo Honda

Toshihiro Otani

Kazuhiro Nishi

A circular accelerator that accelerates charged particles orbiting along an orbital path to a predetermined energy to perform, by deviating the path from the orbital path to an extraction path, extraction of the charged particles exceeding a stable region formed by multipole electromagnets, includes a multipole electromagnet energization control unit setting energization of the multipole electromagnets so that part of the charged particles are deviated to a discarding path other than the extraction path to discard unwanted charged particles, and then setting energization of the multipole electromagnets so that the charged particles orbiting in the orbital path are deviated to the extraction path to perform extraction of the charged particles.

Circular accelerator, circular accelerator operation method, and particle-beam therapy device

A beam shaping device included in a beam transport system is provided with: a pre-stage quadrupole electromagnet that reduces a distribution width of x-angle components that are inclinations in the x-direction of the charged particles in the beam with respect to the traveling direction; a penumbra expander that moderates an end profile of a particle-number distribution of the x-angle components in the beam having passed through the pre-stage quadrupole electromagnet; and a post-stage quadrupole electromagnet that adjusts a betatron phase in a phase-space distribution in the x-direction, of the beam having passed through the penumbra expander; wherein the post-stage quadrupole electromagnet adjusts a phase advance angle of the betatron phase from the penumbra expander to the isocenter, to be in a range of an odd multiple of 90 degrees&#xb1;45 degrees.

Beam transport system and particle beam therapy system

A device controller controls an acceleration-related devices and an extraction-related devices of an accelerator for accelerating and extracting a particle beam, in such a way that the controller checks, at a time point when receiving a master clock pulse, that preparation for operating the acceleration-related devices is completed and then commands the acceleration-related devices to operate in accordance with an operation pattern corresponding to a prescribed energy of the particle beam, and commands the acceleration-related devices to operate in accordance with an extracting operation pattern when an extraction enable signal indicating that the particle beam reaches the prescribed energy is turned ON and an extraction-related device setting-status signal indicating that completion of setting the extraction-related devices for the prescribed energy is ON.

Particle beam therapy device

In a beam transport system, based on a beam temporal-variation related amount that has been calculated by a beam analyzer and that is a beam-position temporal variation amount or a beam diameter at a beam profile monitor, an optical parameter calculator calculates a start-point momentum dispersion function that is a momentum dispersion function (&#x3b7;, &#x3b7;') of a charged particle beam at a start point in design of the beam transport system that is set on a beam trajectory of the accelerator; and calculates optical parameters using, as an initial condition, the start-point momentum dispersion function and a beginning condition at an irradiation position at the time of detecting profile data.

A particle beam treatment system includes an accelerator system that accelerates a charged particle beam and a beam transport system that transports a high-energy beam emitted from the accelerator to an irradiation location, wherein the beam transport system is provided with at least one steering electromagnet and at least one beam position monitor corresponding to the at least one steering electromagnet, and wherein the at least one beam position monitor supplies an excitation current for correcting a beam position, which periodically varies, to the at least one steering electromagnet.

Particle beam treatment system and beam position correcting method thereof

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&#xb0; from the gantry reference angle.

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Tokyo, Japan

Shuhei Odawara