JPH0896995A - Integrated particle beam type accelerator - Google Patents

Abstract

PURPOSE: To make high frequency power sources separately set in a high frequency quadrupole type particle beam type accelerator (RFQ) and an Alvarez type corpuscular beam type accelerator (DTL) commonly usable, and provide a small-sized portable particle beam type accelerator by the simplification of the matching element of a beam transporting system and the compacting of the whole device. CONSTITUTION: This accelerator has an integrated structure in which a RFQ cavity formed of a vein 3 and a cavity wall 2 and a DTL cavity formed of a drift tube 6 and a cavity wall 1 are mutually connected through a common end plate 8. The magnetic fluxes of operating mode of the both are connected by a slot 10 provided on the end plate 8, so that the RFQ can be also driven by the high frequency power supplied to the DTL.

Description

Detailed Description of the Invention

[0001]

INDUSTRIAL APPLICABILITY The present invention can be widely used for a particle linear accelerator, for example, a compact and versatile multipurpose proton linear accelerator, an entrance accelerator for a cancer treatment apparatus, and the like.

[0002]

2. Description of the Related Art A high frequency quadrupole particle linear accelerator (hereinafter,
RFQ) and Alvaret-type particle linear accelerator (hereinafter D)
The particle linear accelerator composed of
Each is stored in a separate tank, and high frequency power is supplied from different high frequency power supplies. Also, RFQ
A beam transport system is usually installed between the
The beam exiting the FQ is shaped in the horizontal and vertical directions by the matching element of this system, and then is incident on the DTL.

[0003]

However, in the above-mentioned conventional particle linear accelerator, there is a problem that the matching element of the beam transport system is complicated and the entire apparatus becomes large.

Therefore, the present invention has been made in view of the above problems of the prior art, and an object thereof is to provide an integrated particle linear accelerator in which the above problems are solved.

[0005]

In order to achieve this object, an integrated particle linear accelerator according to the present invention has a cavity in which a high frequency quadrupole particle linear accelerator and an Alvarre particle linear accelerator are connected via a common end plate. And a slot is provided around the center hole of the end plate to allow the magnetic flux generated on the side of the Alvaré particle linac to leak to the side of the high frequency quadrupole particle linac.

[0006]

The integrated structure in which the RFQ and DTL cavities are connected to each other through a common end plate significantly reduces the distance between them, simplifies the necessary matching elements, and makes the entire apparatus compact. Can be realized. Further, since the slot is provided around the center hole of the end plate, the magnetic flux of the DTL can be leaked to the RFQ, and the RFQ can also be driven by the high frequency power supplied to the DTL.

[0007]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, preferred embodiments of the present invention will be described with reference to the drawings. FIG. 1 shows an embodiment of the present invention (however, 1 Me
An axial sectional view of an integrated particle linear accelerator according to a constant velocity cold model for V protons) is shown in FIG. 2, and a sectional view taken along the line AA in FIG. In RFQ, the cavity formed by the four vanes 3 and the cavity wall 2 resonates in the TE210 (quadrupole) mode, and the electric field generated between the vanes accelerates the particles along the central axis 4. On the other hand, DTL
Then, the drift tube 6 is supported from the cavity wall 1 by the stem 7, and the particles are accelerated by the electric field generated in the gap 9 by the resonance of the TM010 mode.

In the present invention, as shown in FIG. 1, the cavity wall 1 of the Alvaré particle linac (DTL) and the cavity wall 2 of the high frequency quadrupole particle linac (RFQ) share the common end plate 8.
And is joined to the end plate 8 as shown in FIG.
A pair of upper and lower slots 10 are provided around the center hole 5 to allow the magnetic flux of DTL to leak to RFQ.

In this way, the two cavities are joined together through the common end plate 8 and the slot 10 provided in the end plate 8
Magnetic flux of TE210 mode of RFQ and TM010 of DTL
The mode magnetic flux is coupled so that the RFQ can also be driven by the high frequency power supplied to the DTL. Further, in the present invention, by adopting the integrated structure, the RFQ
The distance from the Vane outlet to the DTL drift tube inlet is significantly shortened.

Regarding this embodiment (cold model),
More specifically, the inner diameter and the length of the RFQ cavity wall 2 are 154.5 and 1220.0 mm, and the resonance frequency before tuning is 403 MHz. On the other hand, the DTL is composed of 6 cells having an inner diameter of 460.0 mm and a cell length of 68.5 mm, and the acceleration mode is the 4π mode. Further, although not shown, a side tuner for adjusting the resonance frequency is provided.

FIG. 3 shows the relationship between the end plate 8 and the slot 10. As described above, the elliptical slot 10 bent around the center hole 5 is centered on two points in accordance with the position of the RFQ vane. They are provided symmetrically. However, the layout of the slots is not limited to the vertical direction.

FIG. 4 shows a typical measurement result of the magnetic field distribution of RFQ obtained by adjusting the end tuner gap. The magnetic fields in the four quadrants are well balanced within ± 2.3%, and the axial distribution is uniform within ± 2.3%, and a good electromagnetic field distribution is obtained. Further, FIG. 5 shows a typical measurement result of the average electric field (integrated value of the electric field divided by the cell length) on the central axis of the DTL cell, and the flatness sufficient for practical use is obtained.

[0013]

As is clear from the above description, according to the integrated particle linear accelerator, the RFQ can be driven by the high frequency power supplied to the DTL, so that the high frequency power supply system and control can be simplified. Furthermore, simplification of the beam transport system between RFQ and DTL and downsizing of the entire apparatus can be achieved, and for example, a multi-purpose proton linear accelerator of about 10 MeV can be made portable.

[Brief description of drawings]

FIG. 1 is an axial sectional view of an integrated particle linear accelerator according to an embodiment of the present invention.

FIG. 2 is a sectional view taken along line AA in FIG.

FIG. 3 is an explanatory diagram of end plates and slots.

FIG. 4 is a diagram showing a typical measurement result of a magnetic field distribution in RFQ.

FIG. 5 is a diagram showing a representative measurement result of an average electric field distribution in DTL.

[Explanation of symbols]

 1 DTL Cavity Wall 2 RFQ Cavity Wall 3 RFQ Vane 4 Center Axis 5 Center Hole 6 DTL Drift Tube 7 DTL Stem 8 End Plate 9 DTL Gearup 10 Slot

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor, Minoya Hirota, 3-3-1 Minato Mirai, Nishi-ku, Yokohama-shi, Kanagawa Mitsubishi Nuclear Industry Co., Ltd. No. 1 in Mitsubishi Nuclear Industry Co., Ltd. (72) Inventor Taro Suga 3-3-1 Minatomirai, Nishi-ku, Yokohama-shi, Kanagawa Inside Mitsubishi Nuclear Industry Co., Ltd.

Claims (1)

[Claims] 1. The cavities of the high-frequency quadrupole particle linear accelerator and the Alvare particle linear accelerator are connected through a common end plate, and the Alvare particle linear accelerator side is provided around the center hole of the end plate. An integrated particle linear accelerator characterized in that a slot is provided to allow the generated magnetic flux to leak to the high frequency quadrupole particle linear accelerator side.