WO2015045017A1

WO2015045017A1 - Superconducting magnet, particle beam treatment system, and method for operating superconducting magnet

Info

Publication number: WO2015045017A1
Application number: PCT/JP2013/075817
Authority: WO
Inventors: 文章野田; 貴啓山田; 孝道青木
Original assignee: 株式会社日立製作所
Priority date: 2013-09-25
Filing date: 2013-09-25
Publication date: 2015-04-02
Also published as: JPWO2015045017A1

Abstract

　A reference magnetic field set individually for each patient or affected area is gradually varied between patients or affected areas. In other words, a fundamental magnetic field component for which the time rate of change of the magnetic field is small is excited by an external peripheral superconducting coil (6) and a power source (7) therefor. A magnetic field component which has a large time rate of change whereby the magnetic field is varied at high speed in the vicinity of the reference magnetic field and which is necessary for irradiation of each layer in a patient or affected area, is divided from the fundamental magnetic field component, and the magnetic field component having a large time rate of change is excited by an internal peripheral superconducting coil (8) and power source (9) therefor independent from the coil (6). It is thereby possible to provide a superconducting magnet and a particle ray treatment system using the same whereby quench risk can be reduced relative to the conventional technique and a magnetic field can be varied at high speed.

Description

Superconducting electromagnet, particle beam therapy system, and superconducting electromagnet operation method

The present invention relates to a superconducting electromagnet that needs to change a magnetic field at high speed, a particle beam therapy system using the superconducting electromagnet, and a method for operating the superconducting electromagnet.

As one method of accelerating charged particles in a circular accelerator, Patent Document 1 discloses that the polarization magnetic field required for accelerating charged particles is increased mainly by a second type of deflection coil having a small self-inductance to achieve the target energy. It is described that the high deflection magnetic field intensity required with energy close to is generated mainly by the first type of deflection coil.

Non-Patent Document 1 has a cylindrical magnetic pole and coil shape suitable for forming a wide magnetic field region in both the horizontal direction and the vertical direction, and the coil has a cos θ distribution with a current θ direction distribution. A superconducting electromagnet wound around is described.

JP-A-3-122999

Reflecting the recent aging society, as one of the cancer treatment methods, radiotherapy that is minimally invasive, has less burden on the body, and can maintain a high quality of life after treatment is attracting attention. Among them, a particle beam therapy system using a charged particle beam of accelerated protons or carbon is particularly promising because of excellent dose concentration on the affected area.

This particle beam therapy system includes an accelerator system that adjusts a charged particle beam to energy necessary for treatment, and a beam transport system that transports the charged particle beam extracted from the accelerator to an irradiation chamber. In the future, in order to promote the spread of particle beam therapy systems, downsizing of the system is desired, and the use of superconducting electromagnets is considered as one of the solutions.

In particle beam therapy, a scatterer is used to expand the beam, and a collimator, a bolus, etc. irradiate a beam that matches the shape of the affected area, and a thin beam is scanned with a scanning electromagnet to control the irradiation position. There is a beam scanning irradiation method. In the beam scanning irradiation method, the depth direction of treatment can be adjusted by changing the energy of the beam. In accordance with the energy change in the accelerator system, it is necessary to synchronize and change the magnetic field strength of the electromagnet in order to keep the beam trajectory constant in the beam transport system. If this change takes time, the treatment time becomes longer and the burden on the patient increases. Therefore, a superconducting electromagnet capable of changing the magnetic field at high speed is required in order to achieve both the miniaturization of the system and the shortening of the treatment time. In particular, an electromagnet on the downstream side of the scanning electromagnet scans the beam, so that a beam passing area is wide and a large-diameter superconducting electromagnet is required.

However, the superconducting electromagnet as described in Patent Document 1 has a problem of increasing the magnetizing current due to an increase in excitation current or an increase in the size of the yoke when trying to expand the magnetic field region in the vertical direction due to the magnet shape. It becomes.

The superconducting electromagnet described in Non-Patent Document 1 has a cylindrical magnetic pole and coil shape suitable for forming a wide magnetic field region in both the horizontal and vertical directions, and the coil has a current θ-direction distribution. It is wound to have a cos θ distribution. As other examples of how to wind the coil, there are various winding methods such as double-helic winding as shown in Non-Patent Document 2.

However, in any of the winding methods, the superconducting electromagnet described in Non-Patent Document 1 operates one type of coil (for example, a dipole magnetic field generating coil) with one power source, thus avoiding the occurrence of quenching. It was difficult to change the magnetic field at high speed.

An object of the present invention is to provide a superconducting electromagnet capable of suppressing the quenching risk as compared with the prior art and changing the magnetic field at high speed, a particle beam therapy system using the same, and a method of operating the superconducting electromagnet. .

In order to solve the above problems, for example, the configuration described in the claims is adopted.
The present invention includes a plurality of means for solving the above-described problems. For example, a superconducting electromagnet for deflecting the trajectory of a charged particle, which is a reference magnetic field individually set for each affected part, A first superconducting coil for generating a magnetic field component, a first power source for exciting the first superconducting coil, and the affected part being changed at a higher speed than the first superconducting coil, and the reference magnetic field And a second superconducting coil for generating a magnetic field component for obtaining a desired magnetic field component by reinforcing or attenuating the magnetic field, and a second power source for exciting the second superconducting coil. .

According to the present invention, the first superconducting coil that generates the reference magnetic field having a small time change rate can stably flow a large current, and the second superconducting coil that generates the magnetic field having a large time change rate is necessary. Since the excitation current can be reduced, the risk of quenching can be greatly reduced.

Furthermore, in the case of the electromagnet structure described in Patent Document 1, the iron core is already in a magnetic saturation state during high magnetic field operation in which the magnetic field in the iron core is 1.5 T or more. Magnetic flux does not enter, mainly the magnetic field rise near the coil, and it is necessary to pass a large current in order to change the magnetic field in the necessary magnetic field region (the region described as the beam duct in the present invention and the vacuum duct in Patent Document 1). There is.
On the other hand, according to the present invention, the second superconducting coil can be installed around the necessary magnetic field region, and the magnetic field in the necessary magnetic field region can be changed with a lower current compared with the magnet described in Patent Document 1. In addition to reducing the risk of quenching by separating the conduction coil and the second superconducting coil, it is possible to provide a variable superconducting electromagnet having a more stable high speed magnetic field.

In addition, the second superconducting coil that generates a magnetic field with a large time change rate and the first superconducting coil that generates a magnetic field with a small time change rate can be installed separately. It is possible to reduce the maximum magnetic field strength and the unit time variation of the magnetic field at the position of the first superconducting coil to be generated. For this reason, the superconducting electromagnet which can implement | achieve the variable of the large-diameter high-speed magnetic field which reduced the quench risk can be provided.

And by applying the superconducting electromagnet of the present invention to the particle beam therapy system, the system can be miniaturized by using the superconducting electromagnet. At the same time, by realizing a high-speed magnetic field variable superconducting electromagnet, the energy of the beam irradiated to the patient can be changed at high speed, so that the treatment time can be shortened and the burden on the patient can be reduced.

It is a cross-sectional view which shows an example of the outline of 1st Embodiment of the superconducting electromagnet of this invention. It is a block diagram which shows an example of the outline of arrangement | positioning of the coil and power supply of 1st Embodiment of the superconducting electromagnet of this invention. It is a time chart which shows an example of the suitable electromagnet operation pattern in 1st Embodiment of the superconducting electromagnet of this invention, and the conventional electromagnet operation pattern for a comparison. It is a time chart which shows another example of the suitable electromagnet driving | operation pattern in 1st Embodiment of the superconducting electromagnet of this invention. It is a time chart which shows another example of the suitable electromagnet driving | operation pattern in 1st Embodiment of the superconducting electromagnet of this invention. It is a time chart which shows another example of the suitable electromagnet driving | operation pattern in 1st Embodiment of the superconducting electromagnet of this invention. It is a block diagram which shows schematic structure of 2nd Embodiment of the particle beam therapy system using the superconducting electromagnet of this invention. It is a block diagram which shows schematic structure of 3rd Embodiment of the particle beam therapy system using the superconducting electromagnet of this invention.

Embodiments of a superconducting electromagnet and particle beam therapy system and a superconducting electromagnet operation method according to the present invention will be described below with reference to the drawings.

<First Embodiment>
A first embodiment of a superconducting electromagnet and a superconducting electromagnet operation method according to the present invention will be described with reference to FIGS.
FIG. 1 is a cross-sectional view showing an example of the outline of the first embodiment of the superconducting electromagnet of the present invention, and FIG. 2 is an example of the outline of the arrangement of the coil and the power source of the first embodiment of the superconducting electromagnet of the present invention. FIG. 3 is a time chart showing an example of a suitable electromagnet operation pattern in the first embodiment of the superconducting electromagnet of the present invention, a conventional electromagnet operation pattern for comparison, and FIG. 4 is a diagram illustrating the present invention. FIG. 5 is a time chart showing another example of a suitable electromagnet operation pattern in the first embodiment of the superconducting electromagnet of the present invention. FIG. 5 is still another preferred electromagnet operation pattern in the first embodiment of the superconducting electromagnet of the present invention. FIG. 6 is a time chart showing still another example of a suitable electromagnet operation pattern in the first embodiment of the superconducting electromagnet of the present invention.

As shown in FIG. 1, the superconducting electromagnet of this embodiment generally includes a superconducting coil 1, a yoke 2, a beam duct 3, and a heat insulating container 4.

The superconducting coil 1 includes an outer peripheral side superconducting coil (first superconducting coil) 6 and an inner peripheral side superconducting coil (second superconducting coil) 8 that are installed independently.

As shown in FIG. 2, the coil 6 is connected to a power source 7 (first power source), and the coil 8 is connected to a power source 9 (second power source), and each is connected to an independent power source. The

coils

6 and 8 have a coil shape called cos θ winding.

Returning to FIG. 1, the

coils

6 and 8 are arranged so as to surround a necessary magnetic field region (inside the beam duct 3) so that the current distribution in the θ direction becomes a cos θ distribution. Each of the

coils

6 and 8 is installed in a heat insulating layer constituted by the heat insulating container 4 so that it can be cooled to a very low temperature. A yoke 2 is installed on the outer peripheral side of the

coils

6 and 8 to increase the central magnetic field strength and reduce the leakage magnetic field in the outer peripheral direction.

Next, the difference between the coil 6 and the coil 8 will be described. First, FIG. 3 shows an example of the time change of the magnetic field generated by each coil.
In FIG. 3, (A) shows a magnetic field pattern in a conventional coil constituted by a single coil, and (B) shows a super magnetic field pattern of the present invention in which the same required magnetic field pattern as in (A) is constituted by two types of coils. Each magnetic field pattern in a conductive coil is shown.

As shown by the long broken line in FIG. 3B, the magnetic field pattern excited by the coil 6 generates a reference magnetic field set individually for each affected area. This reference magnetic field is set to a magnetic field corresponding to the deepest part irradiation of each affected part. The time for changing the reference magnetic field between the affected areas is generally several tens of seconds to 1 minute.
In the present invention, the “affected part” is not limited to the affected part to be treated in one patient, and for example, a plurality of treated objects in the case where the energy of the charged particle beam irradiated by the affected part differs greatly in one patient. It also means each “affected area” of the affected area.

On the other hand, the magnetic field pattern excited by the coil 8 is a magnetic field pattern for obtaining a magnetic field pattern necessary for irradiating each layer (several to several hundred layers) obtained by dividing one affected part in the depth direction. That is, as shown by the one-dot chain line in FIG. 3B, the coil 8 has a reference magnetic field that is smaller in intensity than the magnetic field intensity generated by the coil 6 and has a large time change rate in order to realize a necessary magnetic field pattern. This coil generates a magnetic field to be attenuated and changes it at high speed.

Thus, in the coil 6 and the coil 8, as shown in FIG. 3B, the magnetic field strength is not changed in the coil 6 in one affected part, whereas the charged particle beam is applied to each layer in the affected part in the coil 8. The role of changing the intensity of the magnetic field small and at high speed corresponding to the change of the beam energy of the charged particles to irradiate is charged.

More specifically, in the coil 8, the time for changing the magnetic field between the layers is generally as high as several tens of ms to several hundred ms, and is considerably faster than the tens of seconds to one minute of the coil 6. is there.

Thus, when the functions of the coil 8 and the coil 6 are divided and provided, for example, when it is desired to change the magnetic field within one affected part from 2.5T to 2.0T, the coil 8 that changes the magnetic field at high speed is used. A current for generating a magnetic field change of 0.5 T may be supplied, and the coil 6 can be left as it is.
This means that the current density can be reduced when the coil cross-sectional area is considered to be constant, and the magnetic field can be changed at high speed while having a margin against quenching.

Furthermore, different types of superconducting wires are used for the coil 6 and the coil 8.
Specifically, a low-temperature superconducting wire having a critical temperature of less than 40K, such as NbTi, which has a low wire cost, is used for the coil 6 that flows a large current with a relatively small time change rate of the magnetic field. On the other hand, a high-temperature superconducting wire having a critical temperature of 40 K or higher, such as MgB ₂ or yttrium, is used for the coil 8 having a relatively large time change rate of the magnetic field. This further increases the margin for quenching.

According to the first embodiment of the superconducting electromagnet and the superconducting electromagnet operation method of the present invention described above, the reference magnetic field individually set for each patient or affected area is changed gently between patients or affected areas, that is, the magnetic field Is excited by the outer superconducting coil 6 and its power source 7. Then, a magnetic field component having a large time change rate for changing the magnetic field at high speed in the vicinity of the reference magnetic field necessary for irradiating each layer in one patient or one affected area is divided from the basic magnetic field component, and independent of the coil 6. The inner superconductor coil 8 and its power source 9 excite a magnetic field component having a large time change rate.

In the case of a conventional superconducting coil that does not divide the coil as in the present invention, the necessary magnetic field pattern as shown in FIG. 3A can be obtained by configuring all the coils with a high-temperature superconducting wire and changing the magnetic field at high speed. It is possible to get. However, when a high magnetic field is produced in a wide magnetic field region, it is difficult to realize early implementation in terms of performance and cost of the wire. There is also a problem that the quench risk becomes high.
On the other hand, in the present invention, the reference magnetic field excitation coil 6 and the coil 8 for changing the magnetic field strength at high speed with time are independently installed, and the respective coils are excited by

independent power sources

7 and 9, thereby providing a basis. The maximum magnetic field strength at the position of the magnetic field excitation coil 6 and the amount of change of the magnetic field per unit time can be reduced, and a large-diameter high-speed magnetic field variable superconducting electromagnet with reduced quench risk can be realized.
Moreover, the wire materials of the divided coils can be freely combined. For example, when a high-temperature superconducting material is used for the coil 8 that generates a magnetic field having a large time change rate, the exciting current is several minutes that of an integrated coil. It may be about one, and an early high-speed magnetic field variable superconducting electromagnet can be realized. Further, the amount of the high-temperature superconducting wire may be small, and there is an advantage in cost.

In addition, the magnetic field pattern generated by the outer peripheral side superconducting coil 6 and the inner peripheral side superconducting coil 8 is not limited to the pattern shown in FIG. Other examples will be described with reference to FIGS.

FIG. 4 shows an example in which the reference magnetic field generated by the coil 6 is set to the average depth of the affected area. In this case, the maximum magnetic field generated by the coil 6 can be reduced as compared with the combination of magnetic field patterns shown in FIG. The magnetic field generated by the coil 8 reinforces or attenuates the reference magnetic field generated by the coil 6, but the maximum magnetic field can be reduced in the same manner as the coil 6.

FIG. 5 also shows the magnetic field required to irradiate the shallowest part and the deepest part of the reference magnetic field so that the temporal change of the reference magnetic field, which varies from patient to patient, is small. An example based on the closest reference magnetic field average for each patient is shown.
Also in this case, the maximum magnetic field generated by the coil 6 can be reduced as compared with the combination of magnetic field patterns shown in FIG.

Furthermore, FIG. 6 shows an example in which the reference magnetic field generated by the coil 6 is constant. Even in this case, the maximum magnetic field generated by the coil 6 can be reduced as compared with the combination of the magnetic field patterns shown in FIG.

<Second Embodiment>
A second embodiment of the particle beam therapy system of the present invention will be described with reference to FIG.
FIG. 7 is a configuration diagram showing a schematic configuration of a second embodiment of the particle beam therapy system using the superconducting electromagnet of the present invention.

As shown in FIG. 7, the second embodiment of the particle beam therapy system of the present invention generally includes an incident system 100, a synchrotron 200, a high energy beam transport system 300, and an irradiation device 400. Further, a control system (incident system control device 110, synchrotron control device 210, high energy beam transport system control device 310, irradiation system control) that controls the incident system 100, synchrotron 200, high energy beam transport system 300, and irradiation device 400. Apparatus 410) and an overall controller 500 for controlling the entire treatment system.

The incident system 100 is accelerated by an ion source 11, a pre-accelerator 12 such as a linac that accelerates charged particles generated by the ion source 11 to energy suitable for incidence on the synchrotron 200, and the pre-accelerator 12. A transport system (such as the deflecting electromagnet 13 and the quadrupole electromagnet 14) for transporting the charged particle beam to the synchrotron 200 is generally configured.

The synchrotron 200 accelerates the incident beam to a desired energy. The synchrotron 200 includes an incident deflecting device 21 that makes a beam incident, a deflection electromagnet 22 that deflects the incident beam,

quadrupole electromagnets

23 and 24 that converge and diverge the beam, and a high-frequency acceleration cavity 25 that accelerates the beam. And an emission device 26 for taking out the beam from the synchrotron 200 by deflecting the beam trajectory.

A synchrotron control device 210 that controls the synchrotron 200 includes a deflection electromagnet control unit 212 that controls the deflection electromagnet 22, quadrupole

electromagnet control units

213 and 214 that respectively control the

quadrupole electromagnets

23 and 24, and a high-frequency acceleration cavity 25. A high-frequency acceleration control unit 215 for controlling and an extraction device control unit 216 for controlling the extraction device 26 are provided.

Power sources

22a, 23a, 24a, 25a, and 26a are arranged between the

control units

212, 213, 214, 215, and 216 and the respective devices.

The high energy beam transport system 300 is accelerated to a desired energy by the synchrotron 200 and transports the charged particle beam extracted from the emission device 26 to the irradiation device 400. The high energy beam transport system 300 includes a deflection electromagnet 31 that deflects an incident beam and a quadrupole electromagnet 32 that converges and diverges the beam.

The deflection electromagnet 31 is a superconducting electromagnet provided with a plurality of independent coils (the outer peripheral side superconducting coil 6 and its power source 7 and the inner peripheral side superconducting coil 8 and its power source 9) described in the first embodiment. It has been.

The high energy beam transport system control device 310 that controls the high energy beam transport system 300 includes a deflection electromagnet control unit 311 that controls the deflection electromagnet 31 and a quadrupole electromagnet control unit 312 that controls the quadrupole electromagnet 32.
The deflection electromagnet control unit 311 independently controls a power source 7 for exciting the outer superconducting coil 6 and a power source 9 for exciting the inner superconducting coil 8. The quadrupole electromagnet control unit 312 controls a power supply 32 a for exciting the quadrupole electromagnet 32.

The irradiation apparatus 400 adjusts the charged particle beam taken out from the synchrotron 200 and transported by the high energy beam transport system 300 according to the position and shape of the affected area 1001 of the patient 1000 and irradiates the affected area 1001. The irradiation apparatus 400 includes a scanning electromagnet 41 and a beam monitor 42 that change the trajectory of the charged particle beam. In this embodiment, the scanning electromagnet is disposed on the downstream side of the superconducting electromagnet 31, but may be disposed on the upstream side of the superconducting electromagnet 31.

In such a particle beam therapy system, the shape of the three-dimensional affected area 1001 is divided into a plurality of layers in the depth direction, and each layer is selectively irradiated by changing the energy of the emitted beam of the synchrotron 200.
For this purpose, after the beam generated by the incidence system 100 is incident on the synchrotron 200, the deflecting electromagnet 202 is controlled by the accelerator control system 210 in accordance with the irradiation energy pattern for each patient set by the treatment planning apparatus (not shown). The quadrupole electromagnets 203 and 204 and the high-frequency acceleration cavity 205 are controlled and adjusted to predetermined energy by the synchrotron 200.
The beam adjusted to a predetermined energy is taken out from the synchrotron 200 by the emission device 26 and taken over by the high energy beam transport system 300.
In the high energy beam transport system 300, the deflecting electromagnet 31 and the quadrupole electromagnet 32 are controlled by the transport system control device 310 in synchronization with the energy extracted from the synchrotron 200, and the charged particle beam is transported to the irradiation device 400.
In the irradiation apparatus 400, the irradiation beam is scanned two-dimensionally (x direction, y direction) by the scanning electromagnet 41 to give a predetermined dose to each part in the layer of the affected part 1001.

As described above, in the particle beam therapy system according to the present embodiment, when irradiating a plurality of layers in the depth direction of the affected area 1001 of the patient 1000, the energy of the emitted beam of the synchrotron 200 is changed. At this time, a signal is output to the power source 9 of the deflecting electromagnet 31 by the deflecting electromagnet controller 311 of the high energy beam transport system control device 310 so that the charged particle beam is transported to the irradiation device 400. The exciting current of the inner peripheral superconducting coil 8 is adjusted so that a predetermined necessary magnetic field pattern corresponding to the emitted beam energy is obtained. At this time, the deflection electromagnet control unit 311 controls the outer peripheral superconducting coil 6 in the deflection electromagnet 31 and its power supply 7 so that the magnetic field pattern is fixed and not changed.

In the second embodiment of the particle beam therapy system of the present invention, even if the energy of the beam extracted from the synchrotron 200 changes at high speed, the deflecting electromagnet 31 in the transport system 300 also changes the magnetic field at high speed in synchronization with the energy change. The burden on the patient can be reduced by shortening the treatment time. Moreover, since the first embodiment of the superconducting electromagnet described above is provided, the entire treatment system can be downsized by using the superconducting electromagnet.

Note that the present embodiment is not limited to this, and an example in which all of the deflection electromagnets 31 of the high energy beam transport system 300 are the superconducting electromagnets of the first embodiment has been shown. It is not always necessary to be a conductive electromagnet, and a part of the conductive electromagnet can be used.

<Third Embodiment>
A third embodiment of the particle beam therapy system of the present invention will be described with reference to FIG.
FIG. 8 is a configuration diagram showing a schematic configuration of the third embodiment of the particle beam therapy system using the superconducting electromagnet of the present invention.

As shown in FIG. 8, the third embodiment of the particle beam therapy system of the present invention generally includes a cyclotron system 600, a high energy beam transport system 300, and an irradiation device 400. The cyclotron system 600, the high energy beam transport system 300, the control system for controlling the irradiation device 400 (accelerator control device 610, the high energy beam transport system control device 310, the irradiation system control device 410) and the entire treatment system are controlled. And a control device 500.

The cyclotron system 600 includes a cyclotron 61 as an accelerator and an energy changing device 62.

In the cyclotron system 600, the energy is changed by taking out a beam of constant energy from the cyclotron 61 and then controlling the thickness of a metal plate or the like by controlling the energy changing device 62 based on a signal from the accelerator controller 610. This is done by changing and adjusting the energy by passing through the metal plate.

Also in this embodiment, when irradiating a plurality of layers in the depth direction of the affected area 1001 of the patient 1000, the beam transport system 300 after the energy changing device 62 applies the magnetic field of the deflection electromagnet 31 in synchronization with the changed energy. Need to change.
Therefore, a signal is output from the cyclotron system 600 to the power supply 9 of the deflection electromagnet 31 by the deflection electromagnet controller 311 of the high energy beam transport system controller 310 so that the charged particle beam is transported to the irradiation device 400. The exciting current of the inner peripheral superconducting coil 8 is controlled so that a predetermined necessary magnetic field pattern corresponding to the outgoing beam is obtained. At this time, similarly to the second embodiment, the deflection electromagnet control unit 311 controls the outer peripheral superconducting coil 6 in the deflection electromagnet 31 to fix and not change the magnetic field pattern.

Also in the third embodiment of the particle beam therapy system of the present invention, since the first embodiment of the superconducting electromagnet described above is provided, substantially the same effect as in the second embodiment of the particle beam therapy system is obtained. It is done.

<Others>
In addition, this invention is not restricted to said embodiment, A various deformation | transformation and application are possible.

For example, the superconducting electromagnet of the present invention is effective regardless of the type of accelerator or the like that adjusts to the energy required for treatment.

In the above-described embodiment, the case where the superconducting electromagnet of the present invention is provided as a superconducting electromagnet that generates a dipole magnetic field that deflects the beam trajectory has been described. However, a quadrupole magnetic field that converges and diverges the beam, and a higher order The same effect can be obtained for the multipolar magnetic field by applying the superconducting electromagnet of the present invention.
In this case, even a single quadrupole superconducting electromagnet is a functionally coupled superconducting electromagnet as described in Non-Patent Document 1 (a magnet capable of generating a dipole magnetic field and a quadrupole magnetic field with the same magnet). The present invention can also be applied to the above.

1 ... Superconducting coil,
2 ... York,
3 ... Beam duct,
4 ... Insulated container,
6 ... outer peripheral superconducting coil,
7 ... Power supply for outer peripheral superconducting coil,
8 ... Inner circumference superconducting coil,
9 ... Power supply for inner peripheral superconducting coil,
100: Incident system,
11 …… Ion source,
12 ... Pre-stage accelerator,
13: Deflection electromagnet,
14 ... quadrupole magnets,
110 ... Incident system controller,
200 ... Synchrotron,
21 ... Incident deflecting device,
22: deflection electromagnet,
23. Convergence quadrupole electromagnet,
24 ... a dipole quadrupole magnet,
25 ... High-frequency acceleration cavity,
26 ... Ejecting equipment,
210 ... accelerator control device,
300 ... High energy beam transport system,
31 ... Bending electromagnet,
32 ... Quadrupole magnets,
310 ... High energy beam transport system controller,
400 ... Irradiation device,
41 ... Scanning magnet,
42 ... Beam monitor,
410 ... Irradiation system control device,
500 ... Overall control device,
600 ... cyclotron system,
61 ... cyclotron,
62 ... Energy change device.

Claims

A superconducting electromagnet for deflecting the trajectory of charged particles,
A first superconducting coil that generates a magnetic field component serving as a reference magnetic field set individually for each affected area;
A first power source for exciting the first superconducting coil;
A second superconducting coil that generates a magnetic field component for obtaining a desired magnetic field component by changing the affected part at a higher speed than the first superconducting coil and reinforcing or attenuating the reference magnetic field;
A superconducting electromagnet comprising a second power source for exciting the second superconducting coil.
The superconducting electromagnet according to claim 1,
A superconducting electromagnet characterized in that the first superconducting coil and the second superconducting coil have different wire materials.
The superconducting electromagnet according to claim 2,
As a wire of the first superconducting coil, a low temperature superconducting wire having a critical temperature of less than 40K,
A superconducting electromagnet using a high-temperature superconducting wire having a critical temperature of 40K or higher as the wire of the second superconducting coil.
A charged particle beam generator for emitting a charged particle beam;
A beam transport system for guiding the charged particle beam emitted from the charged particle beam generator to the irradiation chamber;
A particle beam therapy system comprising a particle beam irradiation apparatus that irradiates a charged particle beam transported by the beam transport system in accordance with the irradiation target shape of an irradiation object in the irradiation chamber,
The said beam transport system has the superconducting electromagnet of any one of Claims 1 thru | or 3. The particle beam therapy system characterized by the above-mentioned.
A method of operating a superconducting electromagnet for deflecting charged particle trajectories,
Outputting a signal to the first power source to excite a first superconducting coil that generates a magnetic field component serving as a reference magnetic field set individually for each affected area;
After the excitation of the first superconducting coil, a signal is output to the second power source to reinforce or attenuate the reference magnetic field so that a magnetic field component for obtaining a desired magnetic field component is faster than the first superconducting coil. And a step of exciting a second superconducting coil to be generated. A method of operating a superconducting electromagnet.