JP2011113901A - Induction acceleration sector cyclotron - Google Patents

Abstract

The present invention provides an induction accelerating sector cyclotron that accelerates a charged particle beam by an induced voltage in an electromagnet array of a sector cyclotron, and further provides a charged particle beam acceleration method capable of repeatedly and effectively accelerating cluster ions.
A charged particle beam that includes a sector electromagnet array of a sector cyclotron and an induction accelerating cell that is connected to a vacuum chamber in a gap between the sector electromagnets and applies an induced voltage to the charged particle beam, and passes through the conductive acceleration cell. The induction acceleration cyclotron is characterized in that a positive induction voltage for accelerating the charged particle beam in the traveling direction is applied to the charged particle beam in synchronization with the charged particle beam. Furthermore, the charged particle beam was accelerated using the induced acceleration cyclotron, and cluster ions could be accelerated.
[Selection] Figure 1

Description

  An induction acceleration sector cyclotron for accelerating a charged particle beam by an induced voltage in an electromagnet array of the sector cyclotron is provided, and a charged particle beam acceleration method capable of repeatedly and efficiently accelerating cluster ions is also provided.

Such low energy cluster ions of the surface properties of nanometer level by irradiating the material research, such as C ₆₀ has been opened up in recent years various applications. However, the practical means for accelerating these cluster ions has been limited to electrostatic accelerators such as bandegraphs.

In the conventional cycloton, sector focusing cyclotron, and high-frequency synchrotron, the high-frequency cavity is a resonator, so there is a limit to the bandwidth of the variable frequency, and the ratio Z / A of the mass number A and the valence number Z is limited. There were certain restrictions. That is, it is limited to an ion species and a valence state in which Z / A is substantially equal. Particularly the acceleration of large ions significantly mass m, such as cluster ions, such as C ₆₀ was absolutely impossible.

  As shown in Patent Documents 1 to 5, the inventors have already introduced an induction acceleration synchrotron induction acceleration synchroton in which an induction acceleration cell is incorporated in an electromagnet array of synchroton and an induction acceleration voltage (pulse voltage) is applied to a charged particle beam. We are developing. In principle, cluster ions can also be accelerated in the induction acceleration synchrotron. A cluster ion is a molecular ion.

  As for the induction accelerating synchrotron, Patent Document 1 that enables acceleration of all species ions, Patent Document 2 that enables acceleration and confinement in the induction accelerating cell of Patent Document 1, Patent Document 3 that controls synchrotron oscillation, Patent Document 3 Patent Literature 4 relating to application control and Cited Literature 5 for controlling the trajectory of a charged particle beam by induced voltage are disclosed.

JP 2006-310013 A JP 2007-165220 A JP 2007-18757 A JP 2007-18756 A JP 2007-18849 A

  On the other hand, all types of ion accelerators, which are induction-accelerated synchrotrons, can in principle accelerate heavy ions and cluster ions, but the normal magnetic field has a small dynamic range, and electrostatic acceleration is greatly increased. The cluster ions cannot be accelerated to a high energy exceeding this.

  On the other hand, it is also possible in principle to use a large dynamic range (0.1 Tesla to 10 Tesla) of a superconducting electromagnet as a deflection magnet. However, superconducting electromagnets with a large dynamic range do not have sufficient magnetic field uniformity in the low magnetic field region. In addition, the excitation speed of superconducting electromagnets that can be manufactured at present is not so fast that it can be used for a high repetition synchrotron, and it takes time to excite even a very high magnetic field, so it is not suitable for a high repetition accelerator.

  Accordingly, the present invention provides an induction accelerating sector cyclotron that accelerates a charged particle beam by an induced voltage in an electromagnet arrangement of a sector cyclotron, and further provides a charged particle beam acceleration method that can efficiently and realistically accelerate cluster ions. The issue is to provide.

  In order to solve the above problems, the present invention comprises a sector electromagnet array of a sector cyclotron and an induction accelerating cell connected to a vacuum chamber in a gap between the sector electromagnets to apply an induced voltage to a charged particle beam, The induction accelerating cyclotron has a configuration in which a positive induced voltage for accelerating the charged particle beam in the traveling direction is applied to the charged particle beam in synchronization with the charged particle beam passing through the guiding acceleration cell.

  The induction accelerating cell includes a first induction accelerating cell connected to a vacuum chamber in a gap between sector electromagnets and a second induction accelerating cell connected to a vacuum chamber in another gap, and the first induction accelerating cell. And the first coils of the second induction accelerating cell are crossed and connected in series, and the first and second induction accelerating cells simultaneously generate induced voltages in the positive and negative directions by driving one switching power source, and the first, The structure of the induction accelerating cyclotron described above is characterized in that a positive induction voltage for accelerating the charged particle beam in the traveling direction is applied to the charged particle beam in synchronization with the charged particle beam passing through the second induction accelerating cell. . Further, the synchronization is connected to a vacuum chamber of any gap or a gap different from the gap, and a bunch monitor that senses the passage of a charged particle beam is connected, and based on the passing signal of the charged particle beam from the bunch monitor, The induction accelerating cyclotron according to the above, wherein the driving timing of the switching power source is controlled, and a positive induced voltage is applied to the charged particle beam at a timing when the charged particle beam passes through the first and second induction accelerating cells. The configuration was as follows.

  Further, a negative induced voltage that accelerates in the direction opposite to the traveling direction is applied to the head of the charged particle beam in the vacuum chamber of any one of the gaps or another gap different from the gap, and the tail of the charged particle beam The induction accelerating cyclotron according to any one of the above, wherein a third induction accelerating cell for confining a charged particle beam is connected by applying a positive induction voltage that accelerates in the traveling direction.

  In addition, the structure of the induction accelerating sector cyclotron according to any one of the above, wherein the first and second induction accelerating cells are connected to vacuum chambers located in opposing gaps in the ring of the sector cyclotron. It was. The induction accelerating sector cyclotron according to any one of the above, wherein a gradient is provided on the upper and lower magnetic pole surfaces of the sector electromagnet so that an internal space extends toward the center of the ring, and the magnetic field strength of the sector electromagnet is given a gradient. The configuration.

  Then, the charged particle beam acceleration method is characterized in that the charged particle beam of cluster ions is accelerated by the induction acceleration sector cyclotron described in any one of the above.

  Since this invention is the said structure, the following effects are exhibited. That is, by combining an induction acceleration cell with the electromagnet array of the sector cyclotron, it is possible to repeatedly accelerate a cluster ion, such as a bandegraph, which has only an actual acceleration method, such as a bandegraph, to an extremely high energy level. In addition, all the elements in the periodic table, such as conventional atomic ions and their heavy ions, and the charged particle beam of all the valence states that the element can take in principle, the allowable range of the magnetic field strength of the electromagnet Can be accelerated to any energy level.

Further, by adopting induction acceleration, the beam can be accelerated from low energy to high energy, so that the SF cyclotron and the linear accelerator as the pre-stage acceleration which are essential for the conventional sector cyclotron are not required. Therefore, since the beam from the ion source can be directly incident on the sector cyclotron by the injection device, the sector cyclotron can be constructed at a very low cost. Of course, a pre-stage accelerator may be used.

For example, the cluster ions, when accelerated heptavalent C ₆₀ is the (German) Ring Cyclotron scale of extant RIKEN, if the magnetic flux density B = 1.6Tesla between the magnetic poles, from the ion source The directly incident C ₆₀ charged particle beam can be accelerated to about 126 MeV.

It is a plane schematic diagram (an example) of the induction acceleration sector cyclotron which is the present invention. It is an example of the block diagram of the pulse voltage generator for acceleration of a charged particle beam. It is an example of the block diagram of the pulse voltage generator for the confinement of a charged particle beam. It is a cross-sectional schematic diagram of the induction | guidance | derivation acceleration cell connected with the vacuum chamber. It is a vertical cross-sectional schematic diagram of the radial direction from the cyclotron center part of a sector electromagnet. It is a schematic diagram of the drive pattern of an induction acceleration cell.

  Hereinafter, an induction acceleration sector cyclotron and a charged particle beam acceleration method according to the present invention will be described in detail with reference to the drawings.

  As shown in FIG. 1, the induction accelerating sector cyclotron 1 is connected to a sector electromagnet 2 array of sector cyclotrons and a vacuum chamber 13 in a gap 3 between the sector electromagnets 2 to apply an induced voltage to the charged particle beam 10. It consists of induction acceleration cells (first induction acceleration cell 6 (for acceleration), second induction acceleration cell 7 (for acceleration), third induction acceleration cell 8 (for confinement)), and passes through the induction acceleration cell for acceleration. A positive induced voltage that accelerates the charged particle beam 10 in the traveling direction in synchronization with the charged particle beam 10 is applied to the charged particle beam 10. This configuration enables acceleration of the charged particle beam.

  The broken line shown in FIG. 1 is the beam trajectory 10a. The charged particle beam 10 is generated by an ion source and directly incident on the vacuum chamber 13 of the induction accelerating sector cyclotron 1 using the injection device 4. Then, while being accelerated by the induction accelerating cell, it is deflected in the sector electromagnet 2, and the rotation radius is increased and the constant magnetic field is accelerated each time the circuit is repeated. And after completion | finish of acceleration, it takes out out of a ring with the extracting device 5, and is utilized for various uses.

  The acceleration induction cell for acceleration includes a first induction acceleration cell 6 connected to the vacuum chamber 13 in the gap 3 between the sector electromagnets 2 and a second induction acceleration cell 7 connected to the vacuum chamber 13 in the other gap 3. .

Then, the primary coils 7e of the first induction accelerating cell 6 and the second induction accelerating cell 7 are crossed and connected in series, and induced voltages in the positive and negative directions are simultaneously generated in the first and second induction accelerating cells 6 and 7. A positive induced voltage is generated in the charged particle beam 10 that is generated by the control of the apparatus 11 and accelerates the charged particle beam 10 in the traveling direction in synchronization with the charged particle beam passing through the first and second induction accelerating cells 6 and 7. Apply.

  The synchronization is performed by connecting a bunch monitor 9 that senses the passage of the charged particle beam 10 to the vacuum chamber 13 in the gap 3 different from the gap 3, and based on the passage signal 9 a of the charged particle beam 10 from the bunch monitor 9. It is controlled by the voltage generator 11. When the exciting current 11a flows in the direction of the arrow in FIG. 1 from the pulse voltage generator 11, an induced voltage is generated in the first and second induction accelerating cells 6 and 7.

  In the third induction accelerating cell 8 that applies an induction voltage for confining the charged particle beam 10, the generation timing of the induction voltage is controlled by the pulse voltage generator 12 based on the passing signal 9 a from the bunch monitor 9. The pulse voltage generator 12 and the third induction accelerating cell 8 are connected by a primary coil 7e, and the third induction accelerating cell 8 also receives an excitation current 12a from the pulse voltage generator 12 to generate an induction voltage generated by the charged particle beam 10. Apply to.

  The induction accelerating sector cyclotron 1 according to the present invention can reuse the entire system of the sector electromagnet 2 array and the vacuum chamber 13 of the conventional sector cyclotron, and the sector electromagnet 2 and the like. Note that a high-frequency accelerating cavity, a high-frequency source, and a control system therefor are not required as conventional sector cyclotron acceleration means. However, the high-frequency accelerating cavity can also be used as a confining device for the charged particle beam 10 in the present invention depending on the type of the charged particle beam 10.

  In FIG. 1, an example using three induction accelerating cells 6, 7, and 8 has been shown. Is possible. The inventors have already found in Patent Document 2 that, at the time of acceleration of a charged particle beam, an induced voltage for confinement is not necessarily required for each revolution. However, acceleration and confinement of the charged particle beam are desirable because separate control systems are easier to control. Further, as shown in Patent Document 1, each of the acceleration induction cell for acceleration and the induction acceleration cell for confinement is set as one unit, and the generation timing of the induction voltage for acceleration and confinement is determined by separate pulse voltage generators. It is also possible to perform control.

  As shown in FIG. 2, the pulse voltage generator 11 includes a digital signal device 14, a pattern generator 15, a switching power supply 16, a DC charger 17, a transmission line 18, and an induced voltage monitor 19. , The generation timing of the induced voltage 20 generated in the second induction accelerating cell 6, 7) is determined by using the passing signal 9 a of the charged particle beam 10 from the bunch monitor 9 and the induced voltage 20 (see FIG. This is a device for controlling so as to be applied. Details are described in Patent Documents 1 to 5.

  An arrow indicated by a broken line in FIG. 2 is a beam trajectory 10a of the charged particle beam 10. From the inside of the ring, a beam trajectory immediately after incidence, a second beam trajectory, a beam trajectory in the first round before emission, and an outgoing orbit. The beam trajectory. In addition, the lap | rotation in the meantime was represented with the dotted line, and was abbreviate | omitted.

  The bunch monitor 9 is connected to the vacuum chamber 13 so as to surround the entire beam trajectory, and detects the passage of the charged particle beam 10 through the charged particle beam. Then, a passing signal 9a which is a pulse is generated. The detected passage signal 9 a is input to the digital signal device 14 and used for control to synchronize the generation timing of the induced voltage 20 with the passage of the charged particle beam 10.

The switching power supply 16 applies a pulse voltage to the induction accelerating cell via the transmission line 18. High repeatability is possible. The switching power supply 16 generally has a plurality of current paths, adjusts the current passing through each branch, and controls the direction of the current to generate a positive induced voltage 20a and a negative induced voltage 20b in the induction accelerating cell. Let The DC charger 17 supplies power to the switching power supply 16. The on / off operation of the switching power supply 16 is controlled by the pattern generator 15 and the digital signal processing device 14. The induced voltage monitor 19 is a monitor for measuring the induced voltage value applied from the induction accelerating cell.

  The induced voltage 20 is composed of positive and negative induced voltages. The positive induced voltage 20a is an induced voltage for accelerating a part of the charged particle beam 10 in the traveling direction (broken arrow in the figure). The negative induced voltage 20b is an induced voltage that avoids magnetic saturation of the induction accelerating cell. In the induction accelerating cell 8 for confining the charged particle beam 10, the negative induced voltage 20 b is accelerated in the direction opposite to the traveling direction of the charged particle beam 10.

  The pattern generator 15 generates a gate signal pattern 15 that controls the on / off operation of the switching power supply 16. That is, the device converts the current path of the switching power supply 16 into a combination of on and off based on the gate parent signal 14a. The digital signal processing device 14 calculates a gate parent signal 14a which is a signal based on the generation of the gate signal pattern 15a by the pattern generator 15.

  The gate signal pattern 715 is a pattern for controlling the induced voltage 20 applied from the induction accelerating cell. When the induced voltage 20 is applied, it is a signal for determining the application time and generation timing, and a signal for determining a pause time between the positive induced voltage and the negative induced voltage. Therefore, the application timing and application time of the induced voltage 20 can be adjusted according to the length of the charged particle beam 10 accelerated by the gate signal pattern 7j.

  As shown in FIG. 3, the pulse voltage generator 12 has the same configuration as the pulse voltage generator 11, and thus the description of the same configuration is omitted. However, only the driving of the third induction accelerating cell 8 for confining the charged particle beam 10 is controlled. That is, a negative induced voltage 20b is applied to the head of the charged particle beam 10, and a positive induced voltage 20a is applied to the tail of the charged particle. Thereby, the synchronous oscillation of the charged particle beam 10 is controlled, and loss due to the diffusion of the charged particle beam 10 is prevented (referred to as “(charged particle beam) confinement”).

  By incorporating the third induction accelerating cell 8 for confinement and the pulse voltage generator 12 for controlling the driving thereof as the confinement means, the charged particle beam 10 can also be confined by the induced voltage. This also enables acceleration of ion clusters without limiting the type of charged particle beam. Depending on the type of the charged particle beam 10 and the acceleration energy level, a conventional high-frequency acceleration cavity can be used for confinement instead of the induction acceleration cell 8.

Here, the induction accelerating cells (first, second, and third induction accelerating cells 6, 7, and 8) have the same structure in principle as the induction accelerating cells for linear induction accelerators that have been manufactured so far. . Hereinafter, the principle of generation of the induced voltage 20 will be described using the cross section of the second induction accelerating cell 7.

  As shown in FIG. 4, the second induction accelerating cell 7 has a double structure including an inner container 7a and an outer container 7b, and a magnetic body 7c is inserted into the outer container 7b to create an inductance. A part of the inner container 7a connected to the vacuum chamber 13 around which the charged particle beam 10 circulates is made of an insulator 7d such as ceramic.

  When a pulse voltage 16a is applied from the DC charger 17 connected to the switching power supply 16 to the primary coil 7e surrounding the toroidal magnetic body 7c, a primary current (excitation current 11a) flows through the primary coil 7e. The exciting current 11a generates a magnetic flux around the primary coil 7e, and the magnetic body 7c surrounded by the primary coil 7e is excited.

  As a result, the magnetic flux density B penetrating the magnetic body 7c increases with time. At this time, an induction electric field is generated in accordance with Faraday's induction law at the secondary insulator 7d, which is both ends 7f of the conductor inner container 7a, across the insulator 7c. This induction electric field becomes an acceleration electric field 7 g for accelerating the charged particle beam 10. A portion where the acceleration electric field 7g is generated is referred to as an acceleration gap 7h. Therefore, the second induction accelerating cell 7 is a one-to-one transformer.

A switching power supply 16 for generating a pulse voltage 16a is connected to the primary coil 7e of the second induction accelerating cell 7, and the generation of the acceleration electric field 7g can be freely controlled by turning the switching power supply 16 on and off from the outside. it can. Accordingly, the second induction accelerating cell 7 receives the pulse voltage 16 from the switching power supply 16 in the primary coil 7e, and generates the induced voltage 20 that is induced in the secondary insulator 7d and applied to the charged particle beam 10. . The same applies to the first induction acceleration cell 7 and the third induction acceleration cell 8.

  As shown in FIG. 5, the upper and lower magnetic pole surfaces 2a of the sector electromagnet 2 are provided with a gradient 2c so that the internal space is widened toward the ring central portion 1a. On the ring center portion 1a side of the sector electromagnet 2, a magnetic flux density gradient in which the magnetic flux density B decreases toward the ring center 1a occurs due to the distance between the magnetic poles becoming far.

When a charged particle of charge e at mass m moves in a uniform magnetic field of magnetic flux density B at velocity v at right angles to the magnetic field, the Lorentz force F acting on the charged particle is e · v · B. . At this time, if the radius of rotation of the charged particle from the ring center 0 is r, from the condition of the balance between the Lorentz force F and the centrifugal force,
F = mv ² / r = e · v · B (Formula 1)
It becomes.

  Therefore, if the magnetic flux density B on the ring center portion 1a side is low, as is apparent from Equation 1, the rotational radius (ρ1) of the charged particles immediately after incidence increases. As a result, a sufficient space can be secured in the ring center portion 1a for installing the magnetic body 7c on the ring center portion 1a side of the induction accelerating cell and the outer container 7b for storing the magnetic body 7c.

Note that ρ2 in FIG. 5 is a rotation radius at the time of emission. Also, delta ₁ is a difference in rotational radii of the rotational radius and the next lap of the time of incidence (orbital separation width), delta ₂ is a track width of separation before exiting one round and the rotation radius at the time of emission. The orbit separation width differs between the gradient 2c portion of the magnetic pole surface 2b and the flat portion. The gradient portion 2c is wider than the flat portion because the magnetic density decreases. The arrow indicated by r is the radial axis direction.

  FIG. 6A shows the variation in the direction of the induced voltage of the first induction accelerating cell 6 and the second induction accelerating cell. 6B shows the induced voltage value (V1 (t)) of the first induction accelerating cell 6 in (A), and FIG. 6C shows the induced voltage value (V2 (t) of the second induced acceleration cell 7 in (A). )) Is represented by a time axis t.

  As shown in FIGS. 6A to 6C, the first induction accelerating cell 6 and the second induction accelerating cell 7 cross the primary coil with one switching power supply 16 of the pulse voltage generator 11. Connected in series. The exciting current 11a flows through the primary coil 7e (in the direction of the arrow) and the induced voltage (at this timing (t1 <t <t2), the positive induced voltage 2a indicated by the solid line in the first induction accelerating cell 6 is In the two-induction acceleration cell 7, a negative induction voltage 20b) indicated by a solid line is generated. A positive induced voltage 20 a is applied to the charged particle beam 10 to accelerate the charged particle beam 10.

  The direction of the magnetic flux density B at this time is represented in the magnetic body 7c. That is, a black dot on the circle in the magnetic body 7c of the first induction accelerating cell 6 is from the back of FIG. 6, and a circle in the magnetic body 7c of the second induction acceleration cell 7 is from the front to the back. This means that the direction of the magnetic flux density 7i is formed.

  Further, at the time t2 <t <t3 when the charged particle beam 10 reaches the second induction accelerating cell 7, the direction of the pulse voltage 16a from the switching power supply 16 is reversed and the excitation current 11a flows in reverse. In the first induction accelerating cell 6, a negative induced voltage 2b indicated by a broken line is generated, and in the second induced accelerating cell 7, a positive induced voltage 20a indicated by a broken line is generated.

  As shown in FIGS. 6B and 6C, the primary coils 7e of the two first and second induction accelerating cells 6 and 7 are crossed and connected in series as described above. The induced voltages 20 in the positive and negative directions can be simultaneously generated in the second induction accelerating cells 6 and 7. The vertical lines indicated by dotted lines in FIGS. 6B and 6C indicate that the same time (t1, t2, t3) corresponds.

  Therefore, the primary coil 7e of the two first and second induction accelerating cells 6 and 7 is crossed and connected in series, so that the charged particle beam has a positive induced voltage 20a twice around the charged particle beam. Therefore, the charged particle beam 10 can be accelerated very efficiently. In addition, since the generation of the induction voltage 20 can be controlled by driving one switching power supply 16, the control is easy and the initial cost can be reduced.

  When the primary coils 7e of the first induction accelerating cell 6 and the second induction accelerating cell 7 are crossed and connected in series, the first and second induction accelerating cells 6 and 7 are opposed to each other in the sector cyclotron ring. By connecting to the vacuum chamber 13 located in the gap 3, the induction accelerating cyclotron according to the present invention can form the longest charged particle beam 10 and can accelerate the charged particle beam 10 more efficiently.

  In FIG. 6, the positive induction voltage 20a for acceleration and the negative induction voltage 20b for reset are simultaneously generated in pairs within the range of one round time T of the charged particle beam 10. Therefore, the time width of the charged particle beam 10 to be accelerated is inevitably less than half the circulation time T.

  According to the present invention, the accelerated acceleration sector cyclotron and the charged particle beam acceleration method can accelerate cluster ions to low energy levels at an unprecedented high energy level. In addition to the research field of surface physical properties by irradiation, it contributes to the research of physical properties in the deep part of materials. Industrially, in addition to the application of conventional accelerators, it will be possible to improve bulk materials and develop new materials.

DESCRIPTION OF SYMBOLS 1 Induction acceleration sector cyclotron 1a Ring center part 2 Sector electromagnet 2a Magnetic pole 2b Magnetic pole surface 2c Gradient 3 Gap 4 Injector 5 Outlet 6 First induction acceleration cell 7 Second induction acceleration cell 7a Inner container
7b outer container 7c magnetic body 7d insulator 7e primary coil 7f end 7g electric field 7h acceleration gap 7i magnetic flux density 8 third induction acceleration cell 9 bunch monitor 9a passing signal 10 charged particle beam 10a beam trajectory 11 pulse voltage generator 11a excitation Current 12 Pulse voltage generator 12a Excitation current 13 Vacuum chamber 14 Digital signal processor 14a Gate parent signal 14a Gate signal pattern 15 Pattern generator 15a Pattern generator 16 Switching power supply 16a Pulse voltage 17 DC charger 18 Transmission line 19 Induction voltage monitor 20 Inductive voltage 20a Positive induced voltage 20b Negative induced voltage

Claims (7)

A sector cyclotron sector electromagnet array and an induction accelerating cell connected to a vacuum chamber in the gap between the sector electromagnets to apply an induced voltage to the charged particle beam, synchronized with the charged particle beam passing through the conducting acceleration cell. An induction accelerating cyclotron, wherein a positive induced voltage for accelerating a charged particle beam in a traveling direction is applied to the charged particle beam. The induction accelerating cell includes a first induction accelerating cell connected to a vacuum chamber in a gap between sector electromagnets and a second induction accelerating cell connected to a vacuum chamber in another gap. The primary coils of the two induction accelerating cells are crossed and connected in series, and the first and second induction accelerating cells are simultaneously generated in the first and second induction accelerating cells by driving one switching power source. 2. The induction accelerating cyclotron according to claim 1, wherein a positive induction voltage for accelerating the charged particle beam in the traveling direction is applied to the charged particle beam in synchronization with the charged particle beam passing through the induction accelerating cell. The synchronization is performed by connecting a bunch monitor that senses the passage of a charged particle beam to any one of the gaps or a vacuum chamber different from the gap, and the switching is performed based on a passing signal of the charged particle beam from the bunch monitor. 3. The induction according to claim 2, wherein the driving timing of the power source is controlled, and a positive induced voltage is applied to the charged particle beam at a timing when the charged particle beam passes through the first and second induction accelerating cells. Accelerated cyclotron. A negative induced voltage that accelerates in the direction opposite to the traveling direction is applied to the head of the charged particle beam in the vacuum chamber of any one of the gaps or another gap different from the gap, and the traveling direction is applied to the tail of the charged particle beam. 4. The induction accelerating cyclotron according to claim 2, wherein a positive induction voltage for acceleration is applied to the third induction accelerating cell and a third induction accelerating cell for confining the charged particle beam is connected. The said 1st, 2nd induction | guidance | derivation acceleration cell is connected to the vacuum chamber located in the opposing gap in the ring of a sector cyclotron, The Claim 1 characterized by the above-mentioned. Induction acceleration sector cyclotron. 6. The gradient according to claim 1, wherein a gradient is provided on the upper and lower magnetic pole surfaces of the sector electromagnet so as to expand an internal space toward the center of the ring, and the gradient of the magnetic field strength of the sector electromagnet is provided. Induction acceleration sector cyclotron. A charged particle beam acceleration method comprising accelerating a charged particle beam of cluster ions by the induction accelerating sector cyclotron according to any one of claims 1 to 6.

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