JPH0636893A - Particle accelerator - Google Patents

Abstract

PURPOSE:To provide a vacuum chamber itself with beam converging action, contract beam diameter independent from the cross sectional structure of the chamber, and simplify the structure around the chamber. CONSTITUTION:In respective vertical and lateral positions of the wall surface 22a of a vacuum chamber 2, linear conductors 41-44 are arranged within a proper range along the axial direction of the chamber 2 or linearly over the whole circumference. The conductors 41-44 are normal conductors or superconductors, and the surfaces are covered with insulators to be insulated to the chamber 22. When a direct current is sent from a power source 46, a converging force horizontally and vertically acts on an electron beam 10. The intensities of a horizontal converging magnetic field 55 and a vertical converging magnetic field 56 are equal to each other by current regulating mechanisms 48, 50. When the magnetic field is 0 on the central orbit of the chamber 22, an optimum converging state is provided, the electron beam 10 is converged to a minor diameter on the central orbit of the chamber 22, and the performance of a synchrotron radiation 11 can be improved.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a particle accelerator such as a synchrotron, in which the vacuum chamber itself constituting the particle accelerator has a beam converging action.

[0002]

2. Description of the Related Art In recent years, small synchrotrons are expected to be applied as synchrotron radiation (SOR) devices to various fields such as creation of ultra-ultra LSI circuits, diagnosis in the medical field, molecular analysis, and structural analysis. .

An outline of the SOR synchrotron radiation device is shown in FIG. The electron beam 10 accelerated by a linac or the like enters the storage ring 22 from the inflector 18 via the beam transport unit 14. The electron beam 10 incident on the storage ring 22 is focused by the vertical focusing electromagnet 23 (for vertical direction) and the horizontal focusing electromagnet 25 (for horizontal direction) while being given energy in the high-frequency acceleration cavity 21, and the orbit adjusting electromagnet 30. The beam orbit is adjusted by (horizontal direction) and 32 (vertical direction) and is deflected by the deflection electromagnet 24 to be stored in the storage ring 2.
2 Continue to go around. The SOR light 11 generated when being deflected by the deflecting electromagnet 24 is sent to, for example, an exposure device through a beam channel 26 and is used as a light source or the like for creating an ultra-ultra LSI circuit.

[0004]

According to the SOR device of FIG. 2, the beam diameter is determined by the sectional structure (shape, diameter, etc.) of the vacuum chamber-22, and the performance of the SOR light generated by this is also determined. There was a limit. Further, since a large number of electromagnets are arranged in the vacuum chamber 22, there is a drawback that the structure around the vacuum chamber 22 becomes complicated.

The present invention solves the above-mentioned problems in the prior art, and makes it possible to converge the beam diameter to a smaller size regardless of the sectional structure of the vacuum chamber and to simplify the structure around the vacuum chamber. It aims to provide a particle accelerator.

[0006]

SUMMARY OF THE INVENTION The present invention is directed to a plurality of conductors arranged along the axial direction of a wall surface of a vacuum chamber through which a particle beam passes, and these conductors with respect to the particle beam. And a power supply device for supplying a current in the same direction to generate a converging magnetic field.

[0007]

According to the present invention, a plurality of conductors are arranged along the axial direction on the wall surface around the vacuum chamber through which the particle beam passes, and these conductors generate a converging magnetic field for the particle beam. Since the electric currents are made to flow in the same direction, it is possible to give a focusing force to the particle beam by the magnetic field generated from each conducting wire. Therefore, the beam diameter can be satisfactorily converged without being restricted by the sectional structure of the vacuum chamber. It is also possible to simplify the structure around the vacuum chamber by omitting the trajectory adjusting electromagnet and the like.

[0008]

FIG. 1 shows an embodiment in which the present invention is applied to an SOR device. In FIG. 1, (a) is an overall configuration diagram of the SOR device and an enlarged view of the vacuum chamber, and (b) is a wiring diagram of conductors. In FIG. 1A, the electron beam 10 accelerated by a linac or the like enters the storage ring 22 from the inflector 18 via the beam transport unit 14. The electron beam 10 incident on the storage ring 22 is focused by the vertical focusing electromagnet 23 (for vertical direction) and the horizontal focusing electromagnet 25 (for horizontal direction) while being given energy in the high frequency acceleration cavity 21, and is deflected by the deflection electromagnet 24. It is deflected and continues to rotate in the storage ring 22. The SOR light 11 generated when being deflected by the deflecting electromagnet 24 is sent to, for example, an exposure device through a beam channel 26 and is used as a light source or the like for creating an ultra-ultra LSI circuit.

As shown in an enlarged view in FIG. 1 (a), linear conductors 41 to 44 are provided in each of the upper, lower, left and right positions inside the wall surface 22a of the vacuum chamber 22 (accumulation ring).
They are linearly arranged in an appropriate range or along the entire circumference along the axial direction of 2. These straight conductors 41 to 44
Is composed of a normal conducting wire or a superconducting wire, the surface of which is covered with an insulator so as to be insulated from the vacuum chamber 22.

The linear conductors 41 to 44 are connected as shown in FIG. 1 (b), and a direct current power supply 46 causes a current to flow in the same direction. The current adjusting mechanisms 48, 50 are the upper and lower linear conductors 42,
The supply current to 44 and the supply current to the left and right linear conductors 43, 41 are individually adjusted.

FIG. 3 shows how magnetic fields are generated in the vacuum chamber 22 when a current is applied to the linear conductors 41 to 44 from the DC power supply 46. Since the electric currents in the same direction are applied to the linear conductors 41 to 44, the focusing force acts on the electron beam 10 in the horizontal and vertical directions. The current adjusting mechanisms 48 and 50 are adjusted to equalize the strengths of the horizontal focusing magnetic field 55 and the vertical focusing magnetic field 56 (the distances from the central orbit are supplied to the left and right linear conductors 41 and 43). If the magnetic field is set to 0 on the central orbit of the vacuum chamber 22 by increasing the electric current), an optimum converged state can be obtained and the electron beam 1
0 is converged into a small diameter on the central orbit of the vacuum chamber 22, and the performance of the SOR light 11 can be improved. Further, as a result, the orbit adjusting electromagnets 30, 32 of FIG.
Etc. can be omitted.

In FIG. 1, the DC power source 52 is for baking the vacuum chamber 22 using the linear conductors 41 to 44 when the vacuum chamber 22 is initially started up. That is, at the time of baking, the switch 54 is connected to the contact b side, and a large current is supplied from the DC power supply 46 to the linear conductor 4.
1 to 44 are heated and the vacuum chamber 22 is baked.

[0013]

[Other Embodiments] In the above embodiment, the linear conductors 41 are arranged on the upper, lower, left and right sides of the vacuum chamber 22. You can also In addition, the linear conductors 71 to 7 shown in FIG.
It is also possible to arrange a larger number such as eight.

The present invention can also be applied to particle accelerators other than SOR devices. In the case of a proton beam, a converging magnetic field can be obtained by reversing the direction of the current flowing through the straight conductor.

[0015]

As described above, according to the present invention, a plurality of conductors are arranged along the axial direction on the wall surface around the vacuum chamber through which the particle beam passes, and the particle beam is provided on these conductors. Since the electric currents in the same direction that generate the converging magnetic field are caused to flow, it is possible to apply the converging force to the particle beam by the magnetic field generated from each conductor.
Therefore, the beam diameter can be satisfactorily converged without being restricted by the sectional structure of the vacuum chamber. It is also possible to simplify the structure around the vacuum chamber by omitting the trajectory adjusting electromagnet and the like.

[Brief description of drawings]

FIG. 1 is an overall configuration diagram showing an embodiment of the present invention, an enlarged view of a vacuum chamber, and a wiring diagram of a straight conductor.

FIG. 2 is a plan view showing an outline of a conventional SOR device.

FIG. 3 is a cross-sectional view showing how magnetic fields are generated in the vacuum chamber of FIG.

FIG. 4 is a sectional view showing another embodiment of the present invention.

[Explanation of symbols]

 10 Electron Beam (Particle Beam) 22 Vacuum Chamber 22a Vacuum Chamber Wall Surface 41 to 44 Linear Conductor (Director) 46 DC Power Source (Power Source) 55, 56 Converging Magnetic Field

Claims (1)

[Claims] 1. A plurality of conductors arranged along the axial direction on a wall surface around a vacuum chamber through which a particle beam passes, and a plurality of conductors in the same direction for generating a converging magnetic field with respect to the particle beam. A particle accelerator comprising: a power supply device for passing an electric current.