JP3046909B2 - Charged particle beam dump device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a charged particle beam dump device used for a charged particle beam acceleration facility, for example.

[0002]

2. Description of the Related Art FIG.
FIG. 6 is a principle diagram of a beam dump device disclosed in Japanese Unexamined Patent Application Publication No. 6-2006.
In the figure, 1 is a charged particle beam generator, 2 is a charged particle beam acceleration tube, and 1 and 2 constitute a linear acceleration type charged particle beam accelerator. 3 is a deflection electromagnet for deflecting the charged particle beam, 5 is a DC power supply for exciting the deflection electromagnet, 6 is an AC power supply for exciting the deflection electromagnet, 4 is a beam dump body for absorbing energy of the charged particle beam, 7 Denotes a beam trajectory before deflection, and 8 denotes a beam trajectory after deflection.

Next, the operation will be described. The charged particle beam 7 emitted from the charged particle beam accelerators 1 and 2 is
The beam is deflected by exciting the bending electromagnet 3, enters the beam dump main body 4, and disappears as heat energy. The charged particle beam 7 is incident on the beam dump main body 4 while its orbit is swung right and left on the same plane by exciting the bending electromagnet by superimposing an alternating current on a direct current by a direct current power supply 5 and an alternating current power supply 6. Therefore, local concentration in the beam dump main body can be prevented.

[0004]

Although the conventional beam dump device is constructed so as to prevent local heat generation as described above, the incident energy per incident area with respect to a charged particle beam having a high intensity is considered. And the incident surface may be damaged or melted.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problem, and scatters a beam incident on a beam dump main body three-dimensionally to further disperse energy incident on the beam dump main body. Accordingly, it is an object to obtain a highly reliable charged particle beam dump device.

[0006]

According to a first aspect of the present invention, there is provided a charged particle beam dump device, comprising: a plurality of deflection energy supply means for supplying deflection energy having a phase difference and having a periodically changing intensity; And a plurality of beam deflecting means arranged so that the deflecting directions of the charged particle beams are spatially different from each other.

According to a second aspect of the present invention, a plurality of dipole deflecting magnets rotating at different rotational speeds are provided, and the trajectory of the charged particle beam is deflected by each of the dipole deflecting magnets. is there.

According to a third aspect of the present invention, there is provided a rotating deflecting magnet and beam deflecting means for receiving a supply of fixed alternating-current deflecting energy. The trajectory of the charged particle beam is deflected by the rotating deflecting magnet and the beam deflecting means. It is something to do.

[0009]

According to the first aspect of the present invention, the trajectory of the beam incident on the beam dump main body is helically dispersed, and the absorbed energy per unit area of the beam dump main body is reduced.

According to the second aspect of the present invention, the trajectories of the charged particle beam are displaced in the circumferential direction while drawing multiple circles by rotating the two dipole electromagnets at different rotational speeds. And the absorbed energy per unit area of the beam dump body is reduced.

According to the third aspect, the trajectory of the charged particle beam incident on the beam dump main body is displaced in the circumferential direction while drawing a waveform by the rotating dipole deflecting magnet and the fixed AC deflecting electromagnet. Therefore, the absorbed energy per unit area of the beam dump main body is reduced.

[0012]

【Example】

Embodiment 1 FIG. Hereinafter, a first embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a side view showing a schematic configuration of a charged particle beam dump device according to Embodiment 1 of the present invention. In the figure, 1, 2, 4, and 7 are the same as in the conventional example, and the description is omitted. Reference numerals 3a and 3b denote bending electromagnets for deflecting the trajectory of the charged particle beam. 6a and 6b are electromagnets 3a and 3
b. An AC power supply device for exciting b. The power supply device has a phase difference of 90 ° with respect to each output current, and its magnitude is continuously and synchronously changed at a cycle larger than the cycle of the AC power supply. ing. 9 is a vacuum duct. FIG.
3 shows an example of a change in the exciting current of the AC power supplies 6a and 6b.

Next, the operation will be described. The charged particle beam 7 is deflected by the bending electromagnets 3a and 3b having a phase difference of 90 ° between the AC power supply devices 6a and 6b and excited by an alternating current whose size continuously and synchronously changes. The beam enters the beam dump body while drawing a trajectory. This is shown in FIG. In this embodiment, the two bending electromagnets are arranged so that their magnetic flux directions are orthogonal to each other, and the output current of the AC power supply has a phase difference of 90 °. If the shape is set to an appropriate elliptical surface, the direction of the magnetic flux of the deflecting magnet can be set at an arbitrary angle, and the output current of the AC power supply device can have an arbitrary phase difference. Also, if the size is changed appropriately and stepwise, it is not always necessary to change the size synchronously.

Next, a first modification of the first embodiment will be described. In this modification, electrostatic deflection is used as a means for deflecting a charged particle beam. FIG. 4 is a side view showing a schematic configuration of a beam dump device according to a first modification of the first embodiment of the present invention. In the figure, reference numerals 10a and 10b denote deflecting electrodes for deflecting the beam trajectory, and are arranged orthogonally by 90 ° as shown in the figure. Reference numerals 11a and 11b denote deflecting electrode AC voltage power supplies. Each output voltage has a phase difference of 90 °, and the magnitude thereof changes continuously and synchronously as in the first embodiment. ing. The change in the voltage of the deflection electrodes 10a and 10b applied by the AC voltage power supplies 11a and 11b is the same as the change in the current in the first embodiment, and the operation is also the same as in the first embodiment. The deflection electrode is advantageous in that it is small and can be installed in a vacuum duct, and the power supply capacity is small.

Next, a second modification of the first embodiment will be described. In this modification, a multipolar electromagnet which is excited by a polyphase alternating current is used as a means for deflecting a charged particle beam. FIG. 5 is a schematic configuration diagram of a charged particle beam dump device according to a second modification of the first embodiment of the present invention. FIG. 6 is a side view showing the principle diagram. In the figure, 13 is a six-pole electromagnet, 14 is a three-phase AC power supply, and 15 is a current increasing / decreasing device. The two opposite magnetic poles of the six-pole electromagnet 13 are 3
Excitation is performed in the same phase of the phase AC power supply 14, and a rotating magnetic field is formed in a space at the center of each magnetic pole. This can be regarded as equivalent to the combination of the two bending electromagnets in the first embodiment at one location. The operation is the same as that of the first embodiment. It should be noted that the electromagnet is not limited to six poles, and it is clear that the same effect can be obtained if it is a multipolar electromagnet composed of two or more pairs of magnetic poles. Also, as in the first modification, it goes without saying that a deflection electrode can be used instead of the electromagnet.

Embodiment 2 FIG. Hereinafter, a second embodiment of the present invention will be described with reference to the drawings. FIG. 7 is a side view showing a schematic configuration of a beam dump device according to Embodiment 2 of the present invention. In the figure, 16a and 16b are two-pole permanent magnets, and 17 is a rotating device.

Next, the operation will be described. The linear charged particle beam 7 is deflected by a two-pole deflecting magnet as shown in the principle diagram of FIG. 8, but the two-pole deflecting magnets 16a and 16b are rotated by the rotating device 17 at different rotation speeds. As shown in FIG. 9, the incident trajectory is such that it revolves while drawing a circle. The deflection magnets 16a and 16b may be permanent magnets or electromagnets that are excited from the outside. When a permanent magnet is used, an electromagnet power supply is unnecessary,
An inexpensive and highly reliable charged particle beam dump device can be obtained. In the above description, the case where there are two deflecting magnets has been described, but it is also possible to configure with three or more deflecting magnets.

Embodiment 3 FIG. Hereinafter, a third embodiment of the present invention will be described with reference to the drawings. FIG. 10 is a side view showing a schematic configuration of a beam dump device according to Embodiment 4 of the present invention.
In the figure, reference numeral 16a denotes a two-pole deflecting magnet which is rotated by a rotating device 17. Reference numeral 3 denotes a bending electromagnet excited by an AC power supply 6.

Next, the operation will be described. The charged particle beam 7 is deflected by the deflection electromagnet excited by the AC power supply 6, and the dipole deflection magnet 16a is rotated by the rotating device 17, so that the charged particle beam 8 has a crown-shaped incident trajectory as shown in FIG. And diffuses and enters the beam dump body.

[0020]

As described above, in the first aspect of the present invention, deflection energy is supplied from a plurality of deflection energy supply means for supplying deflection energy having a phase difference and periodically changing intensity, and the charged particle beam is supplied. Has a plurality of beam deflecting means arranged so that the deflection directions of the beams are spatially different from each other, so that the diffusion amount of the charged particle beam can be arbitrarily selected. It is possible to make it possible to cool
The charged particle beam dump device can be reduced in size and cost, and at the same time, the reliability can be increased. Further, since there is no mechanical driving unit, the reliability is high, and the quality is improved, for example, the charged particle beam can be diffused at high speed. In addition, it is easy to manufacture and inexpensive.

According to a second aspect of the present invention, a plurality of deflecting magnets for rotating the charged particle beam at different rotational speeds are provided, and the trajectory of the charged particle beam is deflected by each of the bipolar deflecting magnets. Therefore, energy concentration in the beam dump main body is eliminated, and cooling of the beam dump main body becomes easy.

According to a third aspect of the present invention, there is provided a rotating dipole deflecting magnet and beam deflecting means for receiving the supply of AC deflecting energy, and the trajectory of the charged particle beam is deflected by the dipole deflecting magnet and the beam deflecting means. So that there is no energy concentration in the beam dump body,
Cooling of the beam dump body becomes easy. Since the charged particle beam is swept in a circular shape by the rotating deflecting magnet, the excitation of the AC electromagnet may have a constant intensity, and the power source may be a simple AC power source, which is inexpensive. Further, since two different deflecting means of the rotating deflecting magnet and the AC electromagnet are combined, there is an advantage that even if one of the deflecting means breaks down, if one of them operates, damage to the beam dump main body can be reduced.

[Brief description of the drawings]

FIG. 1 is a side view of a charged particle beam dump device according to Embodiment 1 of the present invention.

FIG. 2 shows a beam trajectory of a charged particle beam on a beam dump main body according to the first embodiment of the present invention.

FIG. 3 shows an example of a change in an exciting current of an AC power supply according to the first embodiment of the present invention.

FIG. 4 is a side view of a beam dump device according to a first modification of the first embodiment of the present invention.

FIG. 5 is a schematic configuration diagram of a charged particle beam dump device according to a second modification of the first embodiment of the present invention.

FIG. 6 is a side view showing the principle of a charged particle beam dump device according to a second modification of the first embodiment of the present invention.

FIG. 7 is a side view of a beam dump device according to a second embodiment of the present invention.

FIG. 8 is a principle diagram of a beam dump device according to a second embodiment of the present invention.

FIG. 9 shows a beam trajectory of a charged particle beam on a beam dump main body in Embodiment 2 of the present invention.

FIG. 10 is a side view of a beam dump device according to a third embodiment of the present invention.

FIG. 11 shows a beam trajectory of a charged particle beam on a beam dump main body in Embodiment 3 of the present invention.

FIG. 12 is a principle diagram of a conventional beam dump device.

[Description of Signs] 1 charged particle beam generator 2 charged particle beam accelerator tube 3 deflection electromagnet 4 beam dump main body 5 DC power supply 6 AC power supply 7, 8 beam orbit 9 vacuum duct 10a, 10b deflection electrode 11a, 11b AC voltage power supply 13 6 pole electromagnet, 14 3 phase AC power supply, 15 current increasing / decreasing device 16a, 16b 2 pole bending magnet 17 rotating device

──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Teruji Matsuzaki 1-2-1, Wadazakicho, Hyogo-ku, Kobe Mitsubishi Electric Corporation Kobe Works (72) Inventor Masataka Mizobata 1-chome, Wadasakicho, Hyogo-ku, Kobe-shi 1-2, Mitsubishi Electric Corporation Kobe Works (72) Inventor Hiroyuki Dodate 1-2-1, Wadazakicho, Hyogo-ku, Kobe City Mitsubishi Electric Corporation Kobe Works (58) Investigation field (Int.Cl. ⁷ , DB name) H05H 7/00 G21B 1/00 H05H 1/22

Claims (3)

(57) [Claims] 1. A first energy supplier having a first alternating cycle, wherein a charged particle beam is made to collide with a beam dump body while deflecting its trajectory and disappear.
A step, said first alternating cycle and said first energy
Power supply means and a phase difference
Deflection varying in a second alternating period greater than one alternating period
Second deflection energy supply means for supplying energy;
And from the first and second energy supply means.
Receiving the energy supply, the first energy supplier
How the charged particle beam is deflected by energy from the step
Direction and energy from the second energy supply means.
And the deflection direction of the charged particle beam
A charged particle beam dump device comprising different beam deflection means. 2. A method in which a charged particle beam collides with a beam dump body while deflecting its trajectory and disappears, wherein a plurality of dipole deflecting magnets rotating at different rotational speeds are provided. Wherein the trajectory of the charged particle beam is deflected by means of: 3. A charged-particle beam, which collides with a beam dump body while deflecting its trajectory and disappears, comprises a rotating dipole deflecting magnet and a beam deflecting means fixedly supplied with AC deflecting energy. Have, on
The charged particle beam dump device by a serial two-pole deflection magnets and the beam deflecting means, characterized in that so as to deflect the trajectory of the charged particle beam.