Hitachi, Ltd.

Other

Nippon Telegraph and Telephone Corporation

Junichi Hirota

Kazuo Hiramoto

Masatsugu Nishi

Kenji Miyata

Masahiro Tadokoro

Yoshihisa Iwashita

Masumi Umezawa

Hiroyuki Watanabe

Kazuyoshi Saito

Akira Noda

Akinori Shibayama

Hiroaki Sakurabata

Makoto Inoue

Hiroshi Koh

An electromagnet comprises a pair of magnetic pole and , a return yoke , exciting coils and , etc. In an interior portion of a magnetic pole, plural spacers are provided putting side by side in a horizontal direction. Each of the spaces is an air layer and a longitudinal cross-section is a substantially rectangular shape and the space has a lengthily extending slit shape in a vertical direction against a paper face in FIG. . The plural spaces are mainly arranged toward a right side from a beam orbit center O and an interval formed between adjacent spaces is narrower toward the right side. The electromagnet having a simple magnetic pole structure and a wide effective magnetic field area in a case where a maximum magnetic field strength is increased can be secured.

Electromagnet and magnetic field generating apparatus

An electromagnet comprises a pair of magnetic pole,and,, a return yoke,, exciting coils,and,, etc. In an interior portion of a magnetic pole, plural spacers,are provided putting side by side in a horizontal direction. Each of the spaces,is an air layer and a longitudinal cross-section is a substantially rectangular shape and the space has a lengthily extending slit shape in a vertical direction against a paper face in FIG.,The plural spaces are mainly arranged toward a right side from a beam orbit center O and an interval formed between adjacent spaces is narrower toward the right side. The electromagnet having a simple magnetic pole structure and a wide effective magnetic field area in a case where a maximum magnetic field strength is increased can be secured.

In a radio-frequency accelerating system, a loop antenna is coupled with at least one of a plurality of magnetic core groups each including a plurality of magnetic cores or with at least one of the plurality of magnetic cores, and an impedance adjusting means is connected to the loop antenna. A relatively low voltage is applied to the impedance adjusting means. Therefore, the impedance adjusting means may be a circuit element having a low withstand voltage and hence the radio-frequency accelerating system can be formed to have a small construction.

Radio-frequency accelerating system and ring type accelerator provided

The present invention is to provide a method and an apparatus which are able to inject large electric current to a circular accelerator. In order to inject large electric current, that is, a large number of charged particles, a means is provided for injecting a beam into other region of a vacuum duct than the region which is defined as having a height equivalent to the height of the injected beam and a width from the injected point in the vacuum duct to the symmetrical point to the injected point with respect to the geometrical center of the vacuum duct.

Circular accelerator, method of injection of charged particle thereof,

The present invention provides apparatus for acceleration of a charged particle beam which includes energy means for altering the energy of a circulating beam circulating in the apparatus and means for extracting output beams from the apparatus. Control means are arranged to be operable to alter the energy of the circulating beam using the energy means so as to be able to extract output beams of at least two energies from the apparatus using the means for extracting. Thus there is provided an accelerator, and an extraction method therefor, which is capable of extracting a small diameter beam having a varying energy level. This facilitates improved medical irradiation treatment using the beam.

Particle beam accelerator, and a method of operation

Automatically operated accelerator using obtained operating patterns

An ion beam accelerating device includes an accelerating cavity including an accelerating cavity outer conductor having a space therein, two accelerating cavity inner conductors though which an ion beam passes and which penetrate respective side walls of the accelerating cavity outer conductor and are separated from each other by a gap in the accelerating cavity outer conductor, and a plurality of magnetic cores disposed in the accelerating cavity outer conductor and surrounding one or both of the accelerating cavity inner conductors. The ion beam accelerating device further includes a plurality of high frequency magnetic field generating units equal in number to the magnetic cores for inducing respective high frequency magnetic fields in respective ones of the magnetic cores, thereby generating an accelerating voltage across the gap so as to accelerate the ion beam passing through the accelerating cavity inner conductors. Alternatively, the magnetic cores may be divided into a plurality of groups of magnetic cores, and the ion beam accelerating device may include a plurality of high frequency magnetic field generating units equal in number to the groups of magnetic cores for inducing respective high frequency magnetic fields in respective ones of the groups of magnetic cores.

Ion beam accelerating device having separately excited magnetic cores

The present invention is to provide a method and an apparatus which are able to inject a large amount of charged particles to a circular accelerator. In order to inject a large number of charged particles, the charged particle beams are injected into a region of a vacuum duct other than the region which is defined as having a height equivalent to the height of the injected beam and a width from the injected point in the vacuum duct to the symmetrical point to the injected point with respect to the geometrical center of the vacuum duct.

Circular accelerator, method of injection of charged particles thereof,

A circular accelerator is arranged to circulate a charged particle beam through a bending function provided by a bending magnet, set a tune of the charged particle beam being circulated as it is betatron-oscillated to a predetermined value through the effect of a quadrupole magnetic field, resonate the charged particle beam being circulated at the tune set to the predetermined value in a manner to increase an amplitude of the betatron oscillations over the stability limit of resonance, thereby extracting the charged particle beam. The circular accelerator includes a bending magnet formed to generate a quadrupole magnetic field component for horizontally focusing the charged particle beam being circulated and vertically defocusing the beam and another bending magnet formed to generate a quadrupole magnetic field component for horizontally defocusing the charged particle beam being circulated and vertically focusing the beam. The accelerator is reduced in size, easily operated, and enables to keep the location of the beam extraction and the diameter of the beam constant and output an excellent charged particle beam.

Method for extracting charged particle beam and small-sized accelerator

A small-sized circular accelerator capable of generating radiation of high brightness, an operation method of the circular accelerator, and a semiconductor irradiation system capable of using radiation of high brightness. An electron beam emitted from a pre-accelerator is injected to the inside of the storage ring by an injector, and accelerated and stored. Thereafter, each of insertion devices respectively disposed in linear orbit sections between main bending magnets and auxiliary bending magnets are excited to generate an alternating field therein. A meandering or spiral movement of the electron beam is caused by this alternating field. By superposing radiations emitted from vertexes of the meandering orbit or the spiral orbit, radiation having high brightness is generated.

Circular accelerator, operation method thereof, and semiconductor

A circular accelerator for charged particles in which by accelerated damping of the betatron oscillation, that is, a rapid reduction in a beam size through enhancing the radiation damping after the beam injection, a short period of time injection can be accomplished, and also a large current is capable of being stored through repetition of such beam injections.

Circular accelerator and a method of injecting beams therein

A circular accelerator for extracting a charged-particle beam is arranged to increase displacement of the beam by the effect of the betatron oscillation resonance and increase the betatron oscillation amplitude of the particles, which have initially betatron oscillation within the stability limit for the resonance, to exceed the stability limit thereby extracting the particles exceeding the stability limit of the resonance.

Circular accelerator and method and apparatus for extracting

An acceleration device for charged particles has an acceleration cavity through which passes a beam of the particles. High frequency power from a suitable source is transmitted to the cavity via a suitable transmission means (antenna) to transmit the energy to the particles and so accelerate them. The transmission means is controlled by a suitable control to control the coupling constant of the transmission means when power is applied. Also, the device may have a looped conductor in the cavity controlled by the control to couple to the field in the cavity and to extract power from the field, thereby to control the de-tuning of the applied power relative to the power transmitted to the particles. By controlling the coupling constant and/or the de-tuning, power may be transmitted efficiently to the beam of particles.

Acceleration device for charged particles

When accelerating charged particles on synchrotron acceleration basis by using a circular accelerator having a RF acceleration cavity, the detuned amount representative of an offset between oscillation frequency of a RF oscillator for the RF acceleration cavity and resoance frequency of the RF acceleration cavity and the RF power for supplying the charged particles with energy are controlled in compliance with changes in energy of the charged particles without changing the oscillation frequency. A great number of charged particles injected into the circular accelerator can be accelerated to the ultimate storage energy during the acceleration on synchrotron acceleration basis without causing charged particle beam loss.

Method of synchrotron acceleration and circular accelerator

A lift control system includes a spatial filter producing a signal having various features, a discriminator for discriminating one or more features of the signal, and for producing a control signal when at least one of the features discriminated falls in a predetermined range, and active devices connected to the discriminator. The active devices are made active upon receipt of the control signal.

Growing community of inventors

Hitachi, Japan

Junichi Hirota