JPH08213200A - High frequency device for beam emission and accelerator using the same - Google Patents

Abstract

(57) Abstract: An object of the present invention is to provide a high frequency generator for beam extraction, which is necessary for increasing the betatron oscillation amplitude of the beam so as to emit the beam while changing the beam energy. Especially. An accelerator includes a pre-stage accelerator for generating a proton beam, an injector for injecting the proton beam into the accelerator, a vacuum duct 20 around which the proton beam circulates, a deflection electromagnet for bending the beam orbit 3, and a convergent and divergent beam. A four-pole electromagnet that orbits the accelerator, a six-pole electromagnet that forms the beam stability limit, a high-frequency acceleration cavity that energizes the beam, an electrode that increases the betatron oscillation amplitude of the proton beam, and a beam from the accelerator It is composed of a beam emitting high frequency generator 10 for supplying a high frequency signal 13 to the emitter 6 and the electrode 7 for emitting a beam, a high frequency controller 8 for controlling the beam emitting high frequency generator 10, and the like.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an accelerator, in which a high-frequency electromagnetic field is applied to a charged particle beam circulating in the accelerator to increase the betatron oscillation amplitude of the charged particle beam to increase the charged particle beam. The present invention relates to a high frequency generator for emitting a beam of an accelerator.

[0002]

2. Description of the Related Art As a conventional technique for applying a high-frequency electromagnetic field to a charged particle beam circulating in an accelerator to increase the betatron oscillation amplitude of the charged particle beam and emitting the charged particle beam, Japanese Patent Application Laid-Open No. 5-11183117 has been disclosed. It is written. This makes the magnetic field strength of the bending electromagnet and sextupole electromagnet constant,
Tune (betatron frequency per one revolution of the accelerator) is constant, that is, the magnetic field strength of the quadrupole electromagnet is kept constant, a high-frequency electromagnetic field is applied to the charged particle beam, and the betatron vibration amplitude of the charged particle beam is increased to generate resonance. This is a beam extraction method for emitting a charged particle beam. The high frequency applied to the charged particle beam is a high frequency in which the betatron oscillation amplitude of the charged particle beam increases, that is, a high frequency having a frequency band having the tune width of the charged particle beam circulating in the accelerator.

[0003]

In the above prior art, since the output beam energy is constant, the high frequency applied to increase the betatron oscillation amplitude of the charged particle beam may have a constant frequency band.

However, when the energy of the charged particle beam changes, the orbital frequency of the charged particle beam and the range of the beam energy also change. Therefore, in the conventional technique in which the frequency band is constant, the betatron oscillation amplitude is changed according to the change in energy. It cannot be increased. Therefore, it is difficult to obtain the outgoing beam while changing the beam energy.

Further, in the prior art, the current of the outgoing beam, that is, the intensity of the outgoing beam cannot be controlled with any beam energy.

It is an object of the present invention to provide a high-frequency generator for beam extraction that can change the energy of the outgoing beam and control the intensity of the outgoing beam, and an accelerator using the high-frequency generator for beam extraction. And to provide a method of operating the accelerator.

[0007]

According to the first aspect of the present invention, there is provided a high frequency generator for beam extraction, characterized in that a single frequency generating means generates a single frequency and a band noise generating means has a finite band. Generating a band noise, the high-frequency signal generating means, based on the input single frequency and the band noise, the center frequency of the band noise and the single frequency, and the frequency It is to output a high frequency signal having a width. The frequency width of the high-frequency signal can be arbitrarily set based on the band noise.

According to a second aspect of the present invention, there is provided a high frequency generator for beam emission, wherein the single frequency generating means generates a single frequency.
The band noise generating means generates band noise having a finite band, and the high frequency signal generating means, based on the input single frequency and the band noise, the center frequency of the band noise and the single frequency. And to output a high-frequency signal having a frequency width that is substantially the same as or approximately twice the frequency bandwidth of the band noise.

A feature of the high frequency generator for beam emission of claim 3 is that the single frequency generating means includes frequency changing means.
The frequency changing means changes a single frequency.

With the above characteristics, the single frequency can be changed by the frequency changing means.
When the high frequency generator for beam extraction according to claim 1 is used, the single frequency generating means generates a high frequency signal having a frequency width in which the center frequency of the band noise matches the changed single frequency. Can be output. Claim 2
When the high frequency generator for beam extraction of claim 1 is used, the frequency width of the high frequency signal is almost the same as or approximately twice the frequency width of the band noise, and when the high frequency generator for beam extraction of claim 1 is used. Similar effects are obtained.

A feature of the accelerator of claim 4 is that the high-frequency generator for beam extraction of claim 1 or 2 is used.

Due to the above characteristics, when the high frequency generator for beam extraction according to claim 1 is used, the single frequency generating means generates a single frequency and the band noise generating means generates a band noise having a finite band. Generated, high-frequency signal generation means,
Based on the input single frequency and the band,
Since the center frequency of the band noise and the single frequency coincide with each other and a high frequency signal having a frequency width is output to the electrode, a high frequency electromagnetic field is generated at the electrode, and the betatron oscillation amplitude of the charged particle beam is generated. Can be increased, and the charged particle beam can be emitted. When the high frequency generator for beam extraction according to claim 2 is used, the frequency width of the high frequency signal is substantially the same as or approximately twice the frequency width of the band noise, and the high frequency generator for beam extraction according to claim 1 is used. The same effect can be obtained as in the case of the above.

A feature of the accelerator according to claim 5 is that the output control device controls the single frequency generation means, the band noise generation means or the high frequency signal generation means to control the intensity of the high frequency signal output from the high frequency signal generation means. To change.

With the above characteristics, the high-frequency signal whose intensity is changed can be output to the electrode, so that a high-frequency electromagnetic field whose intensity is changed is generated in the electrode, and the betatron oscillation amplitude of the charged particle beam is further increased. Can be increased. Therefore, the charged particle beam having a changed beam current can be emitted.

A feature of the accelerator according to claim 6 is that the energy detection means detects the beam energy, and the control means changes the frequency of the high frequency power supplied to the high frequency acceleration cavity, and the detected beam is detected. It consists in changing a single frequency based on energy.

With the above characteristics, the beam energy can be changed, and the single frequency can be changed according to the change in the beam energy.
When the high frequency generator for beam extraction according to claim 1 is used, it is possible to output a high frequency signal having a frequency width in which the center frequency of the band noise and the changed single frequency match. A high frequency electromagnetic field is generated in the electrodes, and the betatron oscillation amplitude of the charged particle beam can be increased. Therefore, the charged particle beam with changed beam energy can be emitted. When the high frequency generator for beam extraction according to claim 2 is used, the frequency width of the high frequency signal is substantially the same as or approximately twice the frequency width of the band noise, and the high frequency generator for beam extraction according to claim 1 is used. The same effect can be obtained as in the case of the above.

A feature of the accelerator of claim 7 is that the high-frequency generator for beam extraction of claim 3 is used.

According to the above characteristics, when the high frequency generator for beam extraction according to claim 1 is used, the frequency changing means changes a single frequency, and the single frequency generating means changes the changed single frequency. Since it can be generated, the center frequency of the band noise and the changed single frequency match, and since a high frequency signal having a frequency width is output to the electrode, a high frequency electromagnetic field is generated in the electrode, The betatron oscillation amplitude of the charged particle beam can be increased and the charged particle beam can be emitted. When the high frequency generator for beam extraction according to claim 2 is used, the frequency width of the high frequency signal is substantially the same as or approximately twice the frequency width of the band noise, and the high frequency generator for beam extraction according to claim 1 is used. The same effect can be obtained as in the case of the above.

The feature of the accelerator of claim 8 is that the frequency changing means changes a single frequency based on the orbital frequency of the charged particle beam.

According to the above feature, a single frequency can be changed according to the orbiting frequency of the charged particle beam. Therefore, when the high frequency generator for beam extraction according to claim 1 is used, the center frequency of band noise. A high-frequency signal having a frequency width matching the single frequency and having a frequency width can be output to the electrode, a high-frequency electromagnetic field is generated at the electrode, and the betatron oscillation amplitude of the charged particle beam is increased. You can Therefore, the charged particle beam can be emitted according to the circulating frequency of the charged particle beam. Claim 2
When the high frequency generator for beam extraction of claim 1 is used, the frequency width of the high frequency signal is almost the same as or approximately twice the frequency width of the band noise, and when the high frequency generator for beam extraction of claim 1 is used. Similar effects are obtained.

A feature of the accelerator of claim 9 is that the frequency changing means inputs a preset orbiting frequency of the charged particle beam and changes a single frequency based on the orbiting frequency.

With the above features, a single frequency can be changed in accordance with the preset orbiting frequency of the charged particle beam. Therefore, when the high frequency generator for beam extraction according to claim 1 is used, The center frequency of noise and the single frequency coincide with each other, and a high frequency signal having a frequency width can be output to the electrode, a high frequency electromagnetic field is generated in the electrode, and the betatron oscillation amplitude of the charged particle beam is generated. Can be increased. Therefore, the charged particle beam can be emitted according to the preset orbiting frequency. When the high frequency generator for beam extraction according to claim 2 is used, the frequency width of the high frequency signal is substantially the same as or approximately twice the frequency width of the band noise, and the high frequency generator for beam extraction according to claim 1 is used. The same effect can be obtained as in the case of the above.

A feature of the accelerator of claim 10 is that the frequency detecting means detects the orbiting frequency of the charged particle beam, and the frequency changing means changes a single frequency based on the detected orbiting frequency. .

According to the above feature, the single frequency can be changed according to the change of the circulating frequency of the charged particle beam. Therefore, when the high frequency generator for beam extraction according to claim 1 is used, band noise is reduced. A center frequency and the changed single frequency match, and a high frequency signal having a frequency width can be output to the electrode, a high frequency electromagnetic field is generated in the electrode, and the betatron oscillation amplitude of the charged particle beam is generated. Can be increased. Therefore, the charged particle beam can be emitted even if the circulating frequency changes. Claim 2
When the high frequency generator for beam extraction of claim 1 is used, the frequency width of the high frequency signal is almost the same as or approximately twice the frequency width of the band noise, and when the high frequency generator for beam extraction of claim 1 is used. Similar effects are obtained.

A feature of the accelerator of claim 11 is that the energy detecting means detects the beam energy and the frequency changing means changes a single frequency based on the detected beam energy.

With the above features, a single frequency can be changed according to the change in beam energy. Therefore, when the high frequency generator for beam extraction according to claim 1 is used, the center frequency of the band noise changes. A high frequency signal having a frequency width matching the single frequency and having a frequency width can be output to the electrode, a high frequency electromagnetic field is generated at the electrode, and the betatron oscillation amplitude of the charged particle beam is increased. You can Therefore, even if the beam energy changes, the charged particle beam can be emitted. When the high frequency generator for beam extraction according to claim 2 is used, the frequency width of the high frequency signal is substantially the same as or approximately twice the frequency width of the band noise, and the high frequency generator for beam extraction according to claim 1 is used. The same effect can be obtained as in the case of the above.

A twelfth aspect of the accelerator is characterized in that the magnetic field strength detecting means detects the magnetic field strength of the electromagnet, and the frequency changing means changes a single frequency based on the detected magnetic field strength.

The change in beam energy appears as a change in magnetic field strength of the electromagnet. Due to the above characteristics, a single frequency can be changed according to the change in magnetic field strength. Therefore, when the high frequency generator for beam extraction according to claim 1 is used, the single frequency changed with the center frequency of band noise. It is possible to output a high frequency signal having a frequency width that coincides with one frequency to the electrode, generate a high frequency electromagnetic field at the electrode, and increase the betatron oscillation amplitude of the charged particle beam. Therefore, even if the beam energy changes, the charged particle beam can be emitted. When the high frequency generator for beam extraction according to claim 2 is used, the frequency width of the high frequency signal is substantially the same as or approximately twice the frequency width of the band noise, and the high frequency generator for beam extraction according to claim 1 is used. The same effect can be obtained as in the case of the above.

A feature of the operating method of the accelerator according to claim 13 is that
Band noise generated by detecting the orbital frequency of the charged particle beam, changing the single frequency generated by the single frequency generating means based on the detected orbiting frequency, and generating the single frequency and band noise generating means. Based on, the center frequency of the band noise and the single frequency coincide with each other, and a high frequency signal having a frequency width is output, and the high frequency signal is supplied to the electrode.

According to the above feature, the single frequency can be changed according to the change of the circulating frequency, so that the center frequency of the band noise and the changed single frequency coincide with each other, and the frequency is changed. A high frequency signal having a width can be output to the electrode, a high frequency electromagnetic field is generated in the electrode, and the betatron oscillation amplitude of the charged particle beam can be increased. Therefore, the charged particle beam can be emitted even if the circulating frequency changes.

The feature of the operating method of the accelerator according to claim 14 is that
Band noise generated by detecting the orbital frequency of the charged particle beam, changing the single frequency generated by the single frequency generating means based on the detected orbiting frequency, and generating the single frequency and band noise generating means. Based on, the center frequency of the band noise and the single frequency coincide with each other, and outputs a high frequency signal having a frequency width substantially the same as or approximately twice the frequency width of the band noise. Is supplied to the electrodes. The frequency width of the high-frequency signal can be arbitrarily set based on the band noise.

With the above feature, the single frequency can be changed in accordance with the change in the circulating frequency, so that the center frequency of the band noise and the changed single frequency match, and A high-frequency signal having a frequency width substantially the same as or approximately twice the frequency width of band noise can be output to an electrode, a high-frequency electromagnetic field is generated at the electrode, and the betatron oscillation amplitude of the charged particle beam is increased. You can Therefore, the charged particle beam can be emitted even if the circulating frequency changes.

[0033]

BEST MODE FOR CARRYING OUT THE INVENTION

(Embodiment 1) An accelerator equipped with a high-frequency device 10 for beam extraction, which is a first embodiment of the present invention, will be described with reference to FIG.

The accelerator of this embodiment is used as a medical device that uses a proton beam for cancer treatment and the like.

The accelerator of this embodiment includes a pre-stage accelerator for generating a proton beam, an injector 2 for injecting the proton beam into the accelerator, and a vacuum duct 2 for circulating the proton beam.
0, a bending electromagnet that bends the beam trajectory 3, a quadrupole electromagnet that converges and diverges the beam and orbits the accelerator in a stable manner, a sextupole electromagnet 14 that forms a beam stability limit, a high-frequency acceleration cavity 5 that imparts energy to the beam 5, An electrode 7 for increasing the betatron oscillation amplitude of a proton beam, an emitter 6 for emitting a beam from an accelerator, a high frequency generator 10 for beam extraction for supplying a high frequency signal 13 to the electrode 7, and a high frequency generator 10 for beam extraction. It is composed of a high frequency control device 8 for controlling.

The proton beam generated by the pre-stage accelerator 1 is made incident on the accelerator by the injector 2 and is deflected by the deflecting electromagnet 3.
The orbit is maintained by the quadrupole electromagnet 4 and the vacuum duct 20.
Orbit inside. Energy is applied to the circulating proton beam by the high-frequency acceleration cavity 5.

When the beam is accelerated to the desired energy, the high frequency controller 8 causes the high frequency generator 1 for beam extraction.
By controlling 0, a high frequency voltage is output to the electrode 7. When a high frequency voltage is supplied to the electrode 7, the electrode 7 generates a high frequency electromagnetic field, which increases the betatron oscillation amplitude of the beam. The beam whose betatron oscillation amplitude increases and exceeds the stability limit is emitted from the emitter 6 and is applied to the affected part of the patient 11 in the treatment room 9.

In order to increase the betatron oscillation amplitude, it is necessary to apply a high frequency electromagnetic field having a center frequency corresponding to the orbiting frequency of the beam and a band corresponding to the width of the beam energy range. Therefore, the high frequency signal 13 supplied to the electrode 7 is obtained as follows.

However, the orbital frequency of the beam is frev, the fractional part of the tune, that is, the fractional part of the betatron frequency per revolution of the accelerator is ν, and the width of the betatron frequency corresponding to the maximum width of the beam energy range is Δν. , Integer n (n ≧
0), and these values are determined in advance by the design of the accelerator.

The center frequency f is

[0041]

F = frev · (n + ν) (Equation 1) or

[0042]

F = frev · (n + 1−ν) (Equation 2), the frequency width Δf is

[0043]

(3) Δf = frev · Δν (Equation 3)

By the high frequency generator 10 for beam extraction,
Center frequency f is 1 MHz and frequency width Δf is 50 kHz
The case where the high frequency is generated will be described with reference to FIGS. 2 and 3.

The high frequency generator 10 for beam extraction generates an analog multiplier 21 such as an operational amplifier which is an active element, a sweep generator 22 capable of changing the frequency from 1 MHz to 10 MHz, and a noise signal having a finite frequency band from DC. It is composed of a band noise generator 23.

The signal 24 of the sweep generator 22 and the signal 25 of the band noise generator are input to the multiplier 21.
When the frequency of the signal 24 is 1 MHz and the frequency band of the signal 25 is 0 to 25 kHz, the multiplier 21 uses the high frequency signal 1 having a center frequency f of 1 MHz and a bandwidth Δf of 50 kHz.
3 is output.

When the energy of the orbiting proton beam changes, the width of the orbiting frequency frev and the range of the beam energy changes. In the present embodiment, the betatron corresponding to the maximum width of the changing beam energy widths. Since Δν is set in advance to the width of the frequency, even if the width of the beam energy changes, the change is the frequency width Δf.
include. Therefore, even if the beam energy changes,
A suitable high frequency can be obtained to increase the betatron oscillation amplitude of the proton beam.

The high-frequency controller 8 controls the high-frequency generator 10 for beam extraction so that the high-frequency signal 13 is transmitted to the electrode 7 when the sextupole electromagnet 14 forms the beam stability limit.
Apply to.

At this time, the high frequency signal 1 applied to the electrode 7
By changing the intensity of 3, the intensity of the high frequency electromagnetic field generated in the electrode 7 is changed, and the intensity of the outgoing beam current, that is, the outgoing beam intensity can be changed.

In the present embodiment, the high frequency controller 8 controls the sweep generator 22 or the band noise generator 23 so as to change the intensity of the output 24 or the intensity of the output 25. Can be varied, and thus the beam intensity can be varied. Further, the high frequency control device 8 may control the multiplier 21 to change the intensity of the high frequency signal 13.

Further, if the high frequency control device 8 controls the sweep generator 22 to change the center frequency f in accordance with the orbiting frequency frev, the orbiting frequency fre is generated during acceleration.
The beam can be emitted even when v is changing. Therefore, the beam can be emitted even when the beam energy is changing during the acceleration.

In this embodiment, the sweep generator 22
However, an oscillator having a constant frequency may be used instead of the sweep generator 22, and the oscillation frequency may be changed sequentially.

Next, the high frequency generator 10 for beam emission
FIG. 4 shows an example in which a passive element mixer 31, a frequency sweep sweep generator 32, and a band noise generator 33 having a frequency band are used as multipliers. Since the mixer 31 cannot multiply from DC, the desired high frequency signal 13 cannot be obtained at the same frequency as in the previous example.
As an example, the center frequency of the desired high frequency signal 13 is 1M.
Change from Hz to 10MHz, frequency width is 50kHz
The case will be described with reference to FIG. The sweep generator 32, which sweeps the frequency, changes the frequency from 20 MHz to 2
Sweep 9 MHz. The band noise generator 33 generates noise 35 having a band with a center frequency of 19 MHz and a width of 50 kHz. The sweep generator signal 34 and the band noise generator signal 35 are input to the mixer 31. The output 37 of the mixer 31 is the sweep generator 3
The frequency of 2 ± the frequency of the band noise generator 33. Sweep generator 32 frequency + band noise generator 3
Since the frequency of 3 is not necessary, it can be removed by the low-pass filter 36 to obtain the frequency of the frequency-band noise generator 33 of the sweep generator 32, that is, the desired frequency 13. The above is an example, and the frequency can be freely selected.

According to the accelerator of this embodiment, the proton beam can be emitted even if the beam energy of the circulating proton beam changes. Moreover, since the beam intensity of the proton beam can be changed, the beam intensity can be adjusted depending on the irradiation target in a medical device such as cancer treatment. Further, since the proton beam during acceleration can be emitted, the beam can be irradiated in the depth direction of the affected area of the patient.

(Second Embodiment) An accelerator equipped with the emission control device 60 of the second embodiment will be described with reference to FIG.

In addition to the same structure as the accelerator of the first embodiment, the accelerator of the present embodiment is connected to the deflection electromagnet 3 to detect the magnetic field strength 62, and the clock signal 63 based on the detected magnetic field strength 62. B-clock 19 for outputting the signal, electrode 7
Switch 1 for turning on / off the supply of high-frequency signals to the
5 and the emission control device 60.

The emission control device 60 includes a high frequency control device 8,
It has a power supply controller 18 and a central controller 16.

The high frequency control device 8 has a function of controlling the beam extraction high frequency generation device 10 to change the intensity and center frequency of the high frequency signal 13, as in the first embodiment.

The power supply control device 18 is used for the high frequency acceleration cavity 5
It has a function of controlling the power supply 61 to change the intensity and frequency of the high frequency power supplied to the high frequency acceleration cavity 5.

The central control unit 16 has a preset frequency change (hereinafter referred to as a frequency pattern) in order to obtain an outgoing beam having a target beam energy, and according to the frequency pattern, the high frequency control unit 8 and the power source. It has a function of controlling the control device 18 for use. Further, the central controller 16 has a preset timing pattern for opening and closing the switch 15, and has a function of controlling the high frequency switch 15 in accordance with the timing pattern.

In the accelerator of this embodiment, a control device (not shown) controls the electromagnets such as the deflection electromagnet 3 and its power source in accordance with the orbital frequency of the proton beam in order to maintain the orbit of the proton beam, and the electromagnet. Regulates the strength of the magnetic field created by.

The accelerator of this embodiment is similar to that of the first embodiment,
A beam is injected from the pre-accelerator 1 and the high frequency acceleration cavity 5
Energy is applied, and a high-frequency electromagnetic field is applied by the electrode 7 and the light is emitted.

As described above, in order to increase the betatron oscillation amplitude, the orbital frequency fre of the proton beam is
It is necessary to supply the electrode 7 with a high frequency signal 13 having a center frequency f corresponding to v and a band corresponding to the width of the range of the beam energy.

Also, in order to change the beam energy, it is necessary to supply high frequency power having a frequency fc corresponding to the orbiting frequency frev of the proton beam to the high frequency acceleration cavity 5.

Here, the frequency fc of the high frequency power supplied to the high frequency acceleration cavity 5 and the orbital frequency frev of the beam are

[0066]

## EQU00004 ## There is a relation of frev = fc / h (Equation 4). However, h is a harmonic number, which is a value determined by the design of the accelerator and is given in advance.

The control performed by the emission control device 60 of this embodiment will be described.

The central controller 16 first switches the switch 15
The first frequency fc of the frequency pattern is passed to the high frequency control device 8 and the power supply control device 18 while keeping open.

The high frequency control device 8 obtains the orbiting frequency frev using the relationship of (Equation 4), and the high frequency signal 13 is generated in the beam extraction high frequency generator 10 in the same manner as in the first embodiment.

At the same time, the power supply controller 18 supplies high-frequency power of frequency fc to the high-frequency acceleration cavity 5,
The energy of the circulating proton beam changes.

When the energy of the circulating proton beam is changed, the magnetic field strength of the deflection magnet 3 is changed by the control device (not shown), and the B-clock 19 is the clock signal 6
3 is output.

When the central control unit 16 receives the clock signal 63 from the B-clock 19, the next frequency of the frequency pattern is changed again to the high frequency control unit 8 and the power supply control unit 1.
Pass to 8.

The central controller 16 advances the frequency pattern by repeating the above control, and when the preset target frequency, that is, the target beam energy is reached, the switch 15 is closed and a high frequency signal is sent to the electrode 7. Thirteen
Supply. Then, similarly to the first embodiment, an outgoing beam is obtained.

In this embodiment, the central controller 16 switches the switch 1 after the target frequency of the frequency pattern is reached.
Although it has been set in advance to close No. 5, the switch 15 is closed from the beginning of the frequency pattern to emit the proton beam in the course of acceleration, so that the emitted beam can be obtained while changing the beam energy. .

Further, in the present embodiment, the high frequency control device 8 obtains the circulation frequency frev using the relationship of (Equation 4), but the central control device 16 previously generates the pattern of the circulation frequency frev corresponding to the frequency pattern. It is also possible to set and pass the circulating frequency frev to the high frequency control device 8.

Further, similarly to the first embodiment, the high frequency control device 8 can change the intensity of the high frequency signal 13 of the multiplier 21 to change the beam intensity.

According to the accelerator of this embodiment, a proton beam having an arbitrary beam energy can be emitted.
In the medical device such as cancer treatment using the accelerator of this embodiment,
The proton beam can be irradiated in the depth direction of the affected area. Also,
The beam intensity can be adjusted depending on the irradiation target.

[0078]

According to the high frequency generator for beam extraction of claim 1, the single frequency generating means generates a single frequency, and the band noise generating means generates band noise having a finite band. The signal generating means may output a high-frequency signal having a frequency width in which the center frequency of the band noise and the single frequency match based on the input single frequency and the input band. it can.

According to the high frequency generator for beam extraction of claim 2, the single frequency generating means generates a single frequency,
The band noise generating unit generates band noise having a finite band, and the high frequency signal generating unit generates a center frequency of the band noise and the single frequency based on the input single frequency and the band. Can be output, and a high-frequency signal having a frequency width substantially the same as or twice the frequency width of the band noise can be output.

According to the high frequency generator for beam extraction of claim 3, the single frequency generating means includes the frequency changing means for changing a single frequency, so that the high frequency generator for beam extraction of claim 1 is provided. When used, the center frequency of the band noise matches the changed single frequency, and
A high frequency signal having a frequency width can be output.
When the high frequency generator for beam extraction according to claim 2 is used, the frequency width of the high frequency signal is substantially the same as or approximately twice the frequency width of the band noise, and the high frequency generator for beam extraction according to claim 1 is used. The same action and effect as in the case of being present can be obtained.

According to the accelerator of claim 4, when the high frequency generator for beam extraction of claim 1 is used, the center frequency of the band noise coincides with a single frequency, and the high frequency has a frequency width. Since the signal is output to the electrodes, the charged particle beam can be emitted. When the high frequency generator for beam extraction according to claim 2 is used, the frequency width of the high frequency signal is substantially the same as or approximately twice the frequency width of the band noise, and the high frequency generator for beam extraction according to claim 1 is used. The same action and effect as in the case of being present can be obtained.

According to the accelerator of claim 5, the output control device controls the single frequency generating means, the band noise generating means or the high frequency signal generating means to control the intensity of the high frequency signal output from the high frequency signal generating means. By changing,
Since a high-frequency signal whose intensity is changed can be output to the electrode, a charged particle beam whose beam current is changed can be emitted.

According to the accelerator of claim 6, the control means comprises:
The beam energy can be changed by changing the frequency of the high-frequency power supplied to the high-frequency acceleration cavity, the energy detecting means detects the beam energy, and the control means detects the detected beam. When the high frequency generator for beam extraction according to claim 1 is used by changing the single frequency based on the energy, the center frequency of the band noise and the changed single frequency match, and A high-frequency signal having a width can be output to the electrodes, and a charged particle beam with changed beam energy can be emitted. When the high frequency generator for beam extraction according to claim 2 is used, the frequency width of the high frequency signal is substantially the same as or approximately twice the frequency width of the band noise, and the high frequency generator for beam extraction according to claim 1 is used. The same action and effect as in the case of being present can be obtained.

According to the accelerator of claim 7, the frequency changing means changes the single frequency and the single frequency generating means changes by using the high frequency generator for beam extraction of claim 3. Since a single frequency can be generated, when the high frequency generator for beam extraction according to claim 1 is used, the center frequency of the band noise matches the changed single frequency, and the frequency width is Since the high-frequency signal having the above is output to the electrode, the charged particle beam can be emitted. When the high frequency generator for beam extraction according to claim 2 is used, the frequency width of the high frequency signal is substantially the same as or approximately twice the frequency width of the band noise, and the high frequency generator for beam extraction according to claim 1 is used. The same action and effect as in the case of being present can be obtained.

According to the accelerator of claim 8, the frequency changing means changes the single frequency based on the orbital frequency of the charged particle beam, so that the high frequency generator for beam extraction according to claim 1 is used. In this case, the center frequency of the band noise and the single frequency coincide with each other, and a high frequency signal having a frequency width can be output to the electrodes, and the charged particle beam can be generated according to the orbital frequency of the charged particle beam. Can be emitted.

According to the ninth aspect of the present invention, the frequency changing means inputs the preset orbiting frequency of the charged particle beam and changes a single frequency based on the orbiting frequency. When the high frequency generator for beam extraction of No. 1 is used, a high frequency signal having the center frequency of the band noise and the single frequency coincident with each other and having a frequency width can be output to the electrode, which is set in advance. The charged particle beam can be emitted according to the orbiting frequency. When the high frequency generator for beam extraction according to claim 2 is used, the frequency width of the high frequency signal is substantially the same as or approximately twice the frequency width of the band noise, and the high frequency generator for beam extraction according to claim 1 is used. The same action and effect as in the case of being present can be obtained.

According to the accelerator of claim 10, the frequency detecting means detects the orbital frequency of the charged particle beam, and the frequency changing means changes the single frequency based on the detected orbiting frequency. When the high frequency generator for beam extraction according to claim 1 is used, the center frequency of the band noise and the changed single frequency coincide with each other, and a high frequency signal having a frequency width can be output to the electrode. The charged particle beam can be emitted even when the temperature changes. When the high frequency generator for beam extraction according to claim 2 is used, the frequency width of the high frequency signal is substantially the same as or approximately twice the frequency width of the band noise, and the high frequency generator for beam extraction according to claim 1 is used. The same action and effect as in the case of being present can be obtained.

According to the accelerator of claim 11, the energy detecting means detects the beam energy, and the frequency changing means changes the single frequency based on the detected beam energy. When the high frequency generator for beam extraction is used, the center frequency of the band noise matches the changed single frequency, and a high frequency signal having a frequency width can be output to the electrodes,
A charged particle beam can be emitted even if the beam energy changes. When the high frequency generator for beam extraction according to claim 2 is used, the frequency width of the high frequency signal is substantially the same as or approximately twice the frequency width of the band noise, and the high frequency generator for beam extraction according to claim 1 is used. The same action and effect as in the case of being present can be obtained.

According to the twelfth aspect of the present invention, the magnetic field strength detecting means detects the magnetic field strength of the electromagnet, and the frequency changing means changes a single frequency based on the detected magnetic field strength. In the case of using the high frequency generator for beam extraction of item 1, it is possible to output a high frequency signal having a frequency width in which the center frequency of the band noise coincides with the changed single frequency to the electrode, Since the change in energy appears as a change in magnetic field strength, the charged particle beam can be emitted even if the beam energy changes. When the high frequency generator for beam extraction according to claim 2 is used, the frequency width of the high frequency signal is substantially the same as or approximately twice the frequency width of the band noise, and the high frequency generator for beam extraction according to claim 1 is used. The same action and effect as in the case of being present can be obtained. According to the accelerator operating method of claim 13, the orbiting frequency of the charged particle beam is detected, and the single frequency generated by the single frequency generating means is changed based on the detected orbiting frequency to generate band noise. A center frequency of the band noise and the single frequency match based on the band noise generated by the means and the single frequency; and
By outputting a high-frequency signal having a frequency width and supplying the high-frequency signal to the electrodes, the center frequency of the band noise and the changed single frequency match in accordance with the change of the circulating frequency, and, A high frequency signal having a frequency width can be output to the electrodes, and the charged particle beam can be emitted even if the orbiting frequency changes. According to the accelerator operating method of claim 14, the orbiting frequency of the charged particle beam is detected, and the single frequency generated by the single frequency generating means is changed based on the detected orbiting frequency to generate band noise. Based on the band noise generated by the means and the single frequency, the center frequency of the band noise coincides with the single frequency, and the frequency is approximately the same as or approximately twice the frequency width of the band noise. By outputting a high-frequency signal having a width and supplying the high-frequency signal to the electrodes, the center frequency of the band noise and the changed single frequency are matched according to the change of the circulating frequency, and It is possible to output a high frequency signal having a frequency width that is substantially the same as or approximately twice the frequency width of band noise to the electrodes, and emit the charged particle beam even if the orbiting frequency changes. .

[Brief description of drawings]

FIG. 1 is a block diagram showing a first embodiment in which the present device is applied to a medical device.

FIG. 2 is a block diagram of a high frequency generator for beam extraction, which is configured by an analog multiplier.

FIG. 3 is a block diagram of an example of high frequency generation.

FIG. 4 is a block diagram of a high-frequency generator for beam emission, which is composed of a mixer.

FIG. 5 is a block diagram of an example of high frequency generation.

FIG. 6 is a block diagram showing a second embodiment in which the present device is applied to a medical device.

[Explanation of symbols]

1 ... Pre-stage accelerator, 2 ... Injector, 3 ... Bending electromagnet, 4 ... 4
Polar magnet, 5 ... High-frequency acceleration cavity, 6 ... Emitter, 7 ... Electrode,
8 ... High-frequency control device, 9 ... Treatment room, 10 ... High-frequency generator for beam emission, 11 ... Patient, 13 ... High-frequency signal, 14
... 6-pole electromagnet, 15 ... switch, 16 ... central control unit,
18 ... Power supply control device, 19 ... B-clock, 19, 2
0 ... Vacuum duct, 21 ... Analog multiplier, 22 ... Sweep generator, 23, 33 ... Band noise generator, 31
... mixer, 32 ... sweep generator, 36 ... low-pass filter, 60 ... emission control device, 61 ... power supply.

 ─────────────────────────────────────────────────── ─── Continuation of front page (72) Inventor Masatsugu Nishi 2-2-1 Omika-cho, Hitachi-shi, Ibaraki Hitachi Ltd. Energy Research Laboratory

Claims (14)

[Claims] 1. A high frequency device for beam extraction, which is connected to an electrode for applying a high frequency electromagnetic field to a charged particle beam that orbits an accelerator and supplies a high frequency signal to the electrode, wherein a single frequency generating means for generating a single frequency. A band noise generating means for generating band noise having a finite band; and inputting the single frequency and the band noise, the center frequency of the band noise and the single frequency match, and A high-frequency generator for beam extraction, comprising high-frequency signal generating means for outputting a high-frequency signal having a frequency width. 2. A high frequency device for beam extraction, which is connected to an electrode for applying a high frequency electromagnetic field to a charged particle beam circulating in an accelerator and supplies a high frequency signal to said electrode, wherein a single frequency generating means for generating a single frequency. A band noise generating means for generating band noise having a finite band; and inputting the single frequency and the band noise, the center frequency of the band noise and the single frequency match, and A high-frequency generator for beam extraction, comprising high-frequency signal generating means for outputting a high-frequency signal having a frequency width substantially the same as or approximately twice the frequency width of the band noise. 3. The high frequency generator for beam extraction according to claim 1 or 2, wherein the single frequency generating means includes frequency changing means for changing the single frequency. High frequency generator. 4. A pre-stage accelerator for generating a charged particle beam,
An injector for injecting a charged particle beam into an accelerator, a vacuum duct around which the charged particle beam circulates, an electromagnet arranged along the vacuum duct, a high-frequency acceleration cavity for energizing the charged particle beam, and a charged particle beam. In an accelerator provided with an electrode for increasing the betatron oscillation amplitude of, a high frequency device for beam extraction for supplying a high frequency signal to the electrode, and an emitter for emitting a charged particle beam from an accelerator, the high frequency device for beam extraction is An accelerator, which is the high-frequency device for beam extraction according to claim 1 or 2. 5. An output control device for controlling the single frequency generation means, the band noise generation means or the high frequency signal generation means to change the intensity of the high frequency signal output from the high frequency signal generation means. The accelerator according to claim 4, characterized in that 6. An energy detecting means for detecting beam energy, the frequency of the high frequency power supplied to the high frequency acceleration cavity is changed, and the single frequency is changed based on the detected beam energy. The accelerator according to claim 4, further comprising a control means. 7. A pre-stage accelerator for generating a charged particle beam,
An injector for injecting a charged particle beam into an accelerator, a vacuum duct around which the charged particle beam circulates, an electromagnet arranged along the vacuum duct, a high-frequency acceleration cavity for energizing the charged particle beam, and a charged particle beam. In an accelerator provided with an electrode for increasing the betatron oscillation amplitude of, a high frequency device for beam extraction for supplying a high frequency signal to the electrode, and an emitter for emitting a charged particle beam from an accelerator, the high frequency device for beam extraction is An accelerator according to claim 3, which is the high-frequency device for beam extraction. 8. The accelerator according to claim 7, wherein the frequency changing means changes the single frequency based on the orbital frequency of the charged particle beam. 9. The accelerator according to claim 7, wherein the frequency changing means inputs a preset orbiting frequency of the charged particle beam, and changes the single frequency based on the orbiting frequency. 10. A frequency detecting means for detecting a circulating frequency of the charged particle beam, wherein the frequency changing means changes the single frequency based on the detected circulating frequency. 7 accelerators. 11. The accelerator according to claim 7, further comprising energy detecting means for detecting beam energy, wherein the frequency changing means changes the single frequency based on the detected beam energy. 12. A magnetic field strength detecting means for detecting a magnetic field strength of the electromagnet, wherein the frequency changing means changes the single frequency based on the detected magnetic field strength. 7 accelerators. 13. A signal is supplied to an electrode, and a high-frequency electromagnetic field generated at the electrode is applied to a circulating charged particle beam,
In a method of operating an accelerator that emits the charged particle beam, the frequency of the high frequency power supplied to the high frequency acceleration cavity is changed, the orbital frequency of the charged particle beam is detected, and a single frequency generation unit is generated. A single frequency is changed based on the detected circulating frequency, and based on the single frequency and the band noise generated by the band noise generating means, the center frequency of the band noise and the single frequency are A method for operating an accelerator, characterized in that a high-frequency signal having a matching frequency width is output and the high-frequency signal is supplied to the electrodes. 14. A signal is supplied to an electrode, and a high-frequency electromagnetic field generated at the electrode is applied to a circulating charged particle beam,
In a method of operating an accelerator that emits the charged particle beam, the frequency of the high frequency power supplied to the high frequency acceleration cavity is changed, the orbital frequency of the charged particle beam is detected, and a single frequency generation unit is generated. A single frequency is changed based on the detected circulating frequency, and based on the single frequency and the band noise generated by the band noise generating means, the center frequency of the band noise and the single frequency are A method of operating an accelerator, comprising: outputting a high-frequency signal having a frequency width that is substantially the same as or approximately twice the frequency width of the band noise and supplies the high-frequency signal to the electrodes.