JPH11102800A - Superconducting high-frequency accelerating cavity and particle accelerator - Google Patents

Abstract

PROBLEM TO BE SOLVED: To miniaturize a helium refrigerator for cooling a cavity body by providing a fitting port part of an input coupler with a helium supply port and a helium refrigerator, separate from the helium refrigerator for the cavity body, and separately constituting the cooling systems of the input coupler and cavity body. SOLUTION: A connection part between an input coupler 6 and a beam pipe 7 is provided with a supply port of helium, fed from a helium refrigerator 12a separate from a helium refrigerator 19a for a cavity body 1, and cooling systems of the input coupler 6 and cavity body 1 are constituted separately. More than half of heat creeping into the cavity body 1 from ordinary temperature is therefore cooled, not by the helium refrigerator 10a for cooling the cavity body 1 but by the helium refrigerator 12a which is for exclusive use for cooling the connection part of the input coupler 6. Creeping heat from the ordinary temperature is therefore removed for suppressing the heat quantity entering the hollow body 1.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a superconducting high-frequency accelerating cavity accommodated in a cryostat for accelerating charged particles, and a particle accelerator such as a linear accelerator, a synchrotron and a storage ring provided with the cavity.

[0002]

2. Description of the Related Art A conventional superconducting high-frequency accelerating cavity uses niobium as a superconducting material, and the cavity body is housed in a horizontal cryostat and immersed and cooled by a large amount of liquid helium in the cryostat. Thus, the inner surface of the cavity is maintained in a superconductive state. For example, a superconducting high-frequency accelerating cavity having a resonance frequency of 500 MHz is made of pure niobium having a thickness of 1.5 mm, which is a superconducting material.
Multiple acceleration cavities are mechanically connected.

FIG. 6 is a configuration diagram showing a conventional superconducting high-frequency accelerating cavity. As shown in FIG. 6, a superconducting accelerating cavity body (hereinafter simply referred to as a cavity body) 1 is formed from a niobium material which is a superconducting material, and is manufactured into a shape shown in FIG. 6 by electron beam welding or the like. A helium liquid storage tank 2 for storing liquid helium is provided outside the cavity main body 1, and the cavity main body 1 is immersed in the liquid helium by the helium liquid storage tank 2 and is maintained in a superconducting state. I have.

A radiant heat shield 3 cooled by liquid nitrogen or gas helium is provided in an adiabatic vacuum tank outside the helium liquid storage tank 2, and the radiant heat shield 3 suppresses heat from entering the atmosphere. Outside the helium reservoir 2, a vacuum vessel 4 that constitutes the entire cryostat is provided together with the radiation heat shield 3.

On the other hand, high-frequency power required for beam acceleration is supplied from an input coupler 6 attached to a high-frequency power supply port (hereinafter referred to as an input port) 5 to the acceleration cavity of the cavity body 1 to accelerate the beam. Used for
Since most of the high-frequency power supplied from the input coupler 6 is consumed for accelerating the beam, the input port 5 has a low coupling strength, and is provided in the beam pipe 7 connected to both ends of the cavity body 1. .

[0006] The input coupler 6 is formed of a coaxial tube or a waveguide according to the frequency. Generally, the coaxial tube is used at 1.5 GHz or less. What should be noted here for superconductivity is high-frequency loss and heat penetration from the room temperature side. Usually, the input coupler 6 is manufactured by applying copper plating to stainless steel. Input coupler 6
Is connected to the input port 5 on the side of the cavity body 1.
This is done at a location sufficiently far away from the wire to seal the connection and use either indium wire or ribbon as the sealing material.

In the cavity body 1, when a beam passes through a cavity having a small loss, a harmonic (hereinafter referred to as HOM) is excited, generating a high electromagnetic field or causing beam instability. there is a possibility. for that reason,
ΗThe OM needs to be taken out of the cavity. The {O} coupler 8 is a coupler that takes out only the ΗOM without affecting the beam acceleration mode, and is provided in the beam pipe 7 like the input coupler 6.

A change in pressure or mechanical vibration in the cryostat deforms the cavity body 1 to change the resonance frequency of the cavity body 1, and the change in the resonance frequency is applied to the end of the cavity body 1. Attached piezo element tuner 9
Is corrected by finely adjusting the length of the cavity body 1. Helium is supplied to the helium liquid storage tank 2 from the helium refrigerator 10a via the helium supply port 10, and the cavity main body 1 is cooled by the supplied liquid helium.

[0009]

As described above, in the conventional superconducting high-frequency accelerating cavity having a resonance frequency of 500 MHz, the cavity main body 1 and the input port 5 are housed in the liquid helium liquid reservoir 2 and these are accommodated. By immersing in the liquid helium, the niobium material of the cavity main body 1 was maintained in a superconductive state.

However, the amount of heat entering the cavity body 1 per unit is about 30 W, and the heat of 100 W or more must be cooled by the helium refrigerator 10a together with the amount of heat generated by the high frequency of the cavity body 1. Must. About half of the heat intrusion of the cavity body 1 is caused by the input coupler 6, including the superconducting state holding period except during the cavity operation.
A considerable amount of liquid helium must be consumed for external heat intrusion.

The present invention has been made in view of the above circumstances, and reduces the amount of heat entering the cavity body from the input coupler.
By suppressing the amount of heat generated from the cavity body, the amount of liquid helium consumed by the cavity body is reduced, the structure of the entire helium refrigerator system is simplified, and the superconducting high-frequency accelerating air with a simplified cryostat structure. It is an object to provide a body and a particle accelerator.

[0012]

In order to achieve the above object, a superconducting high-frequency accelerating cavity according to the first aspect of the present invention comprises a cavity main body and helium for bringing the cavity main body to an extremely low temperature state. A liquid storage tank, a helium refrigerator for supplying liquid helium to the helium liquid storage tank, a helium supply port for guiding helium supplied from the helium refrigerator to the helium liquid storage tank, and a helium supply port disposed outside the helium liquid storage tank Radiated heat shield and vacuum vessel, a beam pipe connected to both ends of the cavity body, and an input coupler for supplying high-frequency power to the cavity body, a superconducting high-frequency accelerating cavity, wherein the input coupler In the mounting port part,
A helium refrigerator and a helium supply port are provided separately from the cavity main body, and the input coupler and a cooling system of the cavity main body are separated from each other.

According to a second aspect of the present invention, there is provided a superconducting high-frequency accelerating cavity according to the first aspect, wherein the helium refrigerator and the helium supply port are heat intrusion sources other than the input coupler. Wave couplers and other identifiable heat entry points are provided.

According to a third aspect of the present invention, there is provided a superconducting high-frequency accelerating cavity, wherein the cavity body, a helium liquid storage tank for keeping the cavity body at a very low temperature, and liquid helium supplied to the helium liquid storage tank. A helium refrigerator, a helium supply port for guiding helium supplied from the helium refrigerator to the helium reservoir, a radiant heat shield and a vacuum vessel arranged outside the helium reservoir, and connected to both ends of the cavity body Beam pipe, and a superconducting high-frequency accelerating cavity including an input coupler for supplying high-frequency power to the cavity main body, a harmonic coupler or the like that is a cooling source of the input coupler or a heat intrusion source other than the input coupler The refrigerator that cools each of the identifiable heat entry points is a general-purpose cryogenic refrigerator having two heat stages. And butterflies.

According to a fourth aspect of the present invention, there is provided a superconducting high-frequency accelerating cavity according to the third aspect, wherein the radiation heat shield has the same temperature as the heat stage on the high temperature side of the general-purpose cryogenic refrigerator. A radiant heat shield between the first radiant heat shield and a helium reservoir for accommodating the cavity main body, the second radiant heat having the same temperature as the low-temperature side heat stage of the general-purpose cryogenic refrigerator. A shield is provided, and the input coupler portion and the cavity body are covered with the second radiant heat shield.

According to a fifth aspect of the present invention, there is provided a superconducting high-frequency accelerating cavity according to the third or fourth aspect, further comprising a general-purpose cryogenic refrigerator having two heat stages, and a helium liquid storage tank. A radiant heat shield having the same temperature as that of the high-temperature stage of the general-purpose cryogenic refrigerator is provided on the outer side.

According to a sixth aspect of the present invention, there is provided a superconducting high-frequency accelerating cavity, comprising a cavity main body, a radiant heat shield and a vacuum vessel disposed outside the cavity main body, and beams connected to both ends of the cavity main body. In a superconducting high-frequency accelerating cavity provided with a pipe and an input coupler for supplying high-frequency power to the cavity body, a plurality of general-purpose cryogenic refrigerators having two stages of heat stages are provided. The heat stage on the low-temperature side of the machine is characterized in that the cavity body is connected to the input coupler, a harmonic coupler as a heat intrusion source other than the input coupler, and other identifiable heat intrusion points by a heat transfer path.

The superconducting high-frequency accelerating cavity according to the invention according to claim 7 is the superconducting high-frequency accelerating cavity according to claim 3 or 4, wherein the high-temperature side heat stage is 80K and the low-temperature side heat stage is 20K. It is characterized by being a refrigerator.

The superconducting high-frequency accelerating cavity according to the invention of claim 8 is a superconducting high-frequency accelerating cavity according to claim 5 or 6, wherein the high-temperature side heat stage is 40K and the low-temperature side heat stage is 4K. It is characterized by being a refrigerator.

According to a ninth aspect of the present invention, there is provided a particle accelerator.
A superconducting high-frequency accelerating cavity according to any one of claims 1 to 8 is provided.

[0021]

Embodiments of the present invention will be described below with reference to the drawings.

[First Embodiment] FIG. 1 is a structural view showing a first embodiment of a superconducting high-frequency accelerating cavity according to the present invention.
In addition, about the same component part as the above-mentioned prior art,
6 are given the same reference numerals as in FIG. 6 and detailed description is omitted.

As shown in FIG. 1, the cavity body 1 is made of a niobium material which is a superconducting material into the shape shown in FIG.
Is provided with a helium liquid storage tank 2 for keeping the cryogenic temperature.

The helium liquid storage tank 2 has an axial length up to a connection portion between the cavity main body 1 and the beam pipe 7, and immerses only the cavity main body 1 in liquid helium to maintain a superconducting state. I have. A radiant heat shield 3 and a vacuum container 4 constituting the entire cryostat are provided outside the helium liquid storage tank 2. And radiation heat shield 3
Is provided with a helium supply port 10. By supplying helium to the liquid from the helium supply port 10 into the helium liquid storage tank 2, the cavity body 1 is cooled.

On the other hand, high-frequency power required for beam acceleration is supplied from an input coupler 6 attached to the input port 5 to the acceleration cavity of the cavity body 1 and used for beam acceleration. The input ports 5 are provided in beam pipes 7 connected to both ends of the cavity body 1 for electronic use.

Here, since what must be considered for superconductivity is high-frequency loss and heat penetration from the room temperature side, the helium liquid reservoir 2 for the cavity body 1 is located outside the input coupler 6. Another helium liquid storage tank 11 is provided, and a helium refrigerator 10a for cooling the cavity body 1 is provided.
A helium supply port 12 from a helium refrigerator 12a dedicated to the input coupler 6 is provided.

That is, helium is supplied from the helium supply port 12 attached to the vacuum vessel 4 to the helium liquid storage tank 11 provided outside the input coupler 6 so that the helium liquid is emptied from the input coupler 6. The heat entering the body 1 is reduced.

In the embodiment shown in FIG. 1, the port connecting portions of the monitor port 13 and the monitor probe 14 installed at positions opposite to the input port 5 via the beam pipe 7 are also the same helium refrigerator 12a. The liquid is cooled by supplying helium to the liquid into the helium liquid reservoir 11.

Next, the operation of the first embodiment will be described.

Helium supplied from a helium refrigerator 12a separate from the helium refrigerator 10a for the cavity body 1 is provided at a mounting port portion of the input coupler 6, that is, at a connection portion between the input coupler 6 and the beam pipe 7. The supply port of
Since the input coupler 6 and the cooling system of the cavity body 1 are separated from each other, more than half of the heat that enters the cavity body 1 from room temperature can be removed by the helium refrigerator 10 that cools the cavity body 1.
The cooling is not performed by the helium refrigerator 12a, which cools the connection portion of the input coupler 6 but by the helium refrigerator 12a. As a result, heat entering from room temperature is removed, and the amount of heat input to the cavity body 1 is suppressed.

As described above, according to the present embodiment, the input coupler 6 and the cooling system of the cavity body 1 are separated from each other, so that the helium liquid storage tank 2 of the cavity body 1 is separated from the cavity body 1 by the beam. Since it can be limited from one end of the connection portion to the pipe 7 to the other end of the connection portion, the size of the helium liquid storage tank 2 can be reduced, and accordingly, the cavity body 1 is consumed for cooling. The amount of liquid helium can be reduced, the structure of the cryostat of the cavity body 1 can be simplified, and the helium refrigerator 10 that cools the cavity body 1 can be downsized.

In a superconducting high-frequency accelerating cavity for cooling to a superfluid temperature of helium having excellent high-frequency characteristics,
If only the cavity body 1 is cooled down to the superfluid temperature and the connecting portion of the input coupler 6 is brought into the conventional 4K superconducting or high-temperature superconducting state to reduce the application range of the expensive and complicated superfluid refrigeration system, As a result, the structure of the cryostat of the superconducting high-frequency accelerating cavity based on the superfluid temperature can be simplified at a low cost.

Further, by applying the superconducting high-frequency accelerating cavity of this embodiment to a particle accelerator, the helium refrigeration system of the entire particle accelerator can be downsized.

In the superconducting high-frequency accelerating cavity of the first embodiment, a ΗOM coupler 8 serving as a heat invasion source other than the input port 5, a ΗOM port 15 to which the ΗOM coupler 8 is attached, and other components shown in FIG. Monitor port 13 and monitor probe (high-frequency signal pickup monitor) 14 which are heat intrusion points that can be specified
May be separated from the helium refrigerator 10a of the cavity main body 1 and cooled by another refrigeration system to suppress heat intrusion.

Since the OM coupler 8 and the monitor probe 14 have an extremely small amount of heat penetration as compared with the input coupler 6, they are included in the helium refrigerator 12a of the input coupler 6 as shown in FIG. You may make it. Therefore, by providing a plurality of heat transfer paths from one helium refrigerator 12a for cooling, it is possible to reduce the number of refrigerators that supply helium.

[Second Embodiment] FIG. 2 is a configuration diagram showing a second embodiment of a superconducting high-frequency accelerating cavity according to the present invention.
The same or corresponding parts as those in the first embodiment are denoted by the same reference numerals and described. The same applies to the following embodiments.

In this embodiment, in a refrigeration system for cooling the input coupler 6 and the like by means other than the helium refrigerator 10 of the cavity body 1, a general-purpose cryogenic refrigeration having two heat stages having a helium circulation loop itself. The cooling unit of the input coupler 6 is cooled by a heat transfer action without using liquid helium by using the machine 16.

That is, the general-purpose cryogenic refrigerator 16 configured as a two-stage stage is attached to the vacuum vessel 4, and the first stage, which is a high-temperature stage, is connected to the radiation heat shield 3 of the cryostat of the cavity body 1. It is cooled by heat transfer. The second stage on the low temperature side is directly connected to the input coupler 6 to cool it. At this time, a flexible conductor 16a is provided in the heat transfer portion of the general-purpose cryogenic refrigerator 16 in consideration of heat shrinkage at a low temperature, and the flexible conductor 16a absorbs heat shrinkage and expansion of the device. .

Next, the operation of the second embodiment will be described.

In a refrigeration system for cooling the input coupler 6 and the like by a separate system, a general-purpose cryogenic refrigerator 16 having two heat stages having a helium circulation loop itself is used to cool the input coupler 6 into liquid. Cool to cryogenic temperature by heat transfer without using lithium. That is, by using a general-purpose cryogenic refrigerator 16 that does not directly cool with liquid helium, heat entering the cavity main body 1 from the outside is removed by a heat transfer path on the way, so that heat entering the cavity main body 1 due to factors other than high frequency waves. Heat can be minimized. In addition, the range of using liquid helium can be reduced.

Here, the general-purpose cryogenic refrigerator 16 is a refrigerator in which helium circulates between the refrigerator head and the compressor, and once the cooling pipe is filled with helium, it takes a considerable time ( It can be operated without replenishing helium. As a result, heat entering the cavity body 1 can be reduced, and the amount of helium consumed by the cavity body 1 can be reduced accordingly.

As described above, according to the present embodiment, the cooling range of the helium refrigerator 10 for cooling the cavity main body 1 can be limited to the cavity main body 1. Can be reduced as much as possible. Further, by using the general-purpose cryogenic refrigerator 16 for cooling only the heat generated by the high-frequency characteristics of the cavity body 1, the consumption of liquid helium can be reduced. Furthermore, the internal structure of the cryostat can be simplified, and the vacuum vessel 4
Can also be reduced.

[Third Embodiment] FIG. 3 is a block diagram showing a third embodiment of a superconducting high-frequency accelerating cavity according to the present invention.

In the present embodiment, in addition to the configuration of the second embodiment, two general-purpose cryogenic refrigerators 16 each having two heat stages are installed on the radiant heat shield 3. Besides cooling the coupler 6,
It is used for cooling the radiant heat shield 3 provided outside the helium reservoir 2 of the cavity body 1.

In this embodiment, the radiant heat shield 3
In order to suppress the radiant heat between the helium liquid storage tank 2 and the helium liquid storage tank 2, the second radiant heat shield 17 is connected to the helium liquid storage tank 2 using the second stage, which is the low-temperature stage of the general-purpose cryogenic refrigerator 16. 2 is newly provided outside. That is, in the present embodiment, the second radiant heat shield 17 is provided between the helium liquid storage tank 2 that houses the cavity body 1 and the first radiant heat shield 3.
Cover the input coupler 6 and the cavity body 1.

The first radiant heat shield 3 and the second radiant heat shield 17 can be made of copper as in the prior art. However, since the number of shields is increased by one, the weight and cost are taken into consideration. Manufactured from aluminum, weight and cost increases can be suppressed.

In this embodiment, for example, the temperature of the low-temperature side stage is 20 K, and the temperature of the high-temperature side stage is 80 K.
A temperature of K is suitable.

Next, the operation of the third embodiment will be described.

The radiant heat shield 3 in the adiabatic vacuum chamber of the cryostat of the cavity body 1 is used as a first shield, a second radiant heat shield 17 is newly provided, and the general-purpose cryogenic refrigerator 16 is connected to the input coupler 6 only. Instead, the two stages of the high-temperature side and the low-temperature side are connected to the first radiant heat shield 3 and the second radiant heat shield 17, respectively, and are used for cooling the cryostat of the cavity main body 1, so that the cavity main body 1
The amount of heat entering the device can be reduced. As a result, not only heat input from the input coupler 6 but also heat intrusion into the cavity body 1 due to radiation or the like can be removed only by the general-purpose cryogenic refrigerator 16.

As described above, according to the present embodiment, the cryostat of the cavity body 1 is merely heated by the general-purpose cryogenic refrigerator 16 without using liquid nitrogen or gas helium, which has conventionally cooled the radiant heat shield 3. Cooling of the heat shield becomes possible. Therefore, it is possible to reduce heat intrusion from the atmosphere side due to radiation and heat transfer into the helium liquid storage tank 2 in which the cavity body 1 is immersed in liquid helium, and accordingly, the amount of helium consumed by the cavity body 1 is reduced. be able to.

Further, by forming the first and second two-stage radiant heat shields from aluminum or the like, the support and the like can be simplified, and as a result, a cryostat with a simplified structure can be manufactured.

In the case of the present embodiment, for example, a temperature of 20K is most suitable for the low-temperature side stage and a temperature of 80K is suitable for the high-temperature side stage.

[Fourth Embodiment] FIG. 4 is a structural view showing a fourth embodiment of a superconducting high-frequency accelerating cavity according to the present invention.

In this embodiment, instead of the general-purpose cryogenic refrigerator 16 having two heat stages in the third embodiment, a general-purpose cryogenic refrigerator 19 having two more low-temperature stages is used. The first and second radiant heat shields are integrated to form a radiant heat shield 20 with a single-stage shield structure as in the first and second embodiments. The radiation heat shield 20 is made of copper or aluminum.

In this embodiment, the second stage on the low-temperature side of the general-purpose cryogenic refrigerator 19 having two low-temperature heat stages is also connected to the connection between the input port 5 and the input coupler 6. Have been. Further, the stage on the low-temperature side of the input port 5 is connected to the HOM port 15, which is a connection portion of the OM coupler 8 and the monitor probe 14, and the monitor port 1 by the heat transfer path 21.
3 and cooled.

The heat transfer path 21 can have good flexibility and thermal conductivity by laminating high purity aluminum sheets and then bonding them together.

In this embodiment, for example, the temperature of the low-temperature side stage is 4K, and the temperature of the high-temperature side stage is 40K.

Next, the operation of the fourth embodiment will be described.

Instead of the general-purpose cryogenic refrigerator 16, a general-purpose cryogenic refrigerator 19 having a lower-temperature heat stage is used, and cooled by liquid nitrogen or helium gas in a vacuum chamber of a hollow cryostat. The connected heat shield is connected to the stage on the high temperature side of the general-purpose cryogenic refrigerator 19 and cooled.

The stage on the low temperature side of the general-purpose cryogenic refrigerator 19 is connected to the helium liquid storage tank 2 containing the cavity body 1 to assist in cooling the cavity body 1. Thus, the first radiant heat shield provided in the second embodiment can be omitted, and a two-stage structure of the conventional helium liquid reservoir 2 and the radiant heat shield 20 provided in the vacuum heat insulating layer can be obtained.

In addition to the cavity main body 1 provided in the helium liquid storage tank 2, the beam pipe 7, the input port 5 part outside the helium liquid storage tank 2, and the ΗOM port 15 And the portion up to the monitor port 13 can be cooled to a superconducting state without cooling with liquid helium.

As described above, according to the present embodiment, the amount of heat entering the cavity body 1 can be reduced by reducing the temperature of the radiant shield to one stage as in the conventional case and further reducing the temperature of the radiant shield. . Further, by forming the radiation heat shield 20 from aluminum, the structure of the cryostat can be reduced in weight and simplified.

Further, only the cavity body 1 having a large influence on the high-frequency characteristics is brought into a superfluid state of 1.8 K, and the input port 6 and the beam pipe 7 with little high-frequency loss are provided in two stages without using liquid helium. The second stage on the low temperature side of the general-purpose cryogenic refrigerator 19 is used, and can be distinguished from the conventional 4K superconducting state by heat transfer.

[Fifth Embodiment] FIG. 5 is a structural view showing a fifth embodiment of a superconducting high-frequency accelerating cavity according to the present invention.

In the present embodiment, the hollow body 1
The helium liquid storage tank 2 that accommodates the helium is eliminated, and a plurality of two-stage general-purpose cryogenic refrigerators 19 having a further lower temperature heat stage as in the fourth embodiment (three in this embodiment) are provided.
Attached, of which two general purpose cryogenic refrigerators 19
Is connected to the cavity main body 1 by the heat transfer path 23.

Further, the low-temperature side stage of another general-purpose cryogenic refrigerator 19 is connected to the input port 6 and the #OM port 14 by another heat transfer path 21 as in the fourth embodiment, and cools them. . In the cryostat, a radiation heat shield 20 is provided outside the cavity body 1, and the outside of the radiation heat shield 20 is surrounded by the vacuum vessel 4.

Therefore, in the present embodiment, in a cavity in which the calorific value due to the beam loss in the cavity is relatively small, liquid helium is not used for the cavity cryostat, and all of heat intrusion from the outside and heat generation of the cavity itself are eliminated. Is cooled by heat transfer from the low-temperature stage of the general-purpose cryogenic refrigerator 19.

In this embodiment, for example, the most suitable temperature is 4K for the low-temperature side heat stage and 40K for the high-temperature side heat stage.

Next, the operation of the fifth embodiment will be described.

In a cavity having a small current amount and a relatively small beam loss in the cavity body 1, the low-temperature of the two-stage general-purpose cryogenic refrigerator 19 having a further lower heat stage without directly cooling with liquid helium is used. The cavity body 1 is cooled to the superconducting state only by the side cooling heat.

If the cooling capacity of one cavity is insufficient, the cavity body 1 is cooled by arranging a plurality of general-purpose cryogenic refrigerators 19. This eliminates all liquid helium that directly cools the cavity, simplifies the structure of the cavity cryostat, and a large-scale helium refrigeration system that was previously indispensable for superconducting high-frequency acceleration cavities. Can be eliminated.

As described above, according to the present embodiment, by removing the helium liquid reservoir 2 from the cryostat of the cavity, not only the cryostat can be made smaller and simpler than the conventional one, but also the liquid outside the cavity can be removed. In addition to supplying helium to the cavity, it is not necessary to install an expensive and complicated helium refrigeration system in the cavity that liquefies helium vaporized by heat generated from the cavity and circulates helium in the liquid.

[Application Examples] Although described in the first embodiment, in addition to this, any one of the superconducting high-frequency accelerating cavities of the second to fifth embodiments may be used as a linear accelerator or a synchrotron as a particle accelerator. Alternatively, by applying the present invention to a storage ring, the structure of the entire linear accelerator and the entire cryostat of the ring can be simplified, and the total length of the linear accelerator and the total length of the ring can be reduced. Also, because helium consumption can be reduced,
The helium refrigeration system as a whole can be reduced.

[0074]

As described above, according to the first aspect of the present invention,
According to the superconducting high-frequency accelerating cavity described in Nos. 6 to 6, a cryogenic refrigerator that does not directly cool with a helium is provided in a separate refrigeration system other than the cavity main body, such as a helium, in the input coupler portion that accounts for a large factor in heat intrusion from the outside , The conventional helium refrigerator can be limited to the cavity body, and the consumption of liquid helium can be reduced accordingly. Therefore, the structure of the cryostat of the superconducting high-frequency accelerating cavity can be manufactured with a simpler structure than before, and the helium refrigerator that cools the cavity body can be downsized.

Further, as described in claim 7, the superconducting high-frequency accelerating cavity according to any one of claims 1 to 6 is used for a particle accelerator such as a linear accelerator, a synchrotron, or a storage ring, thereby achieving helium refrigeration. The entire equipment including the system can be simplified, and the entire system can be made compact.

[Brief description of the drawings]

FIG. 1 is a configuration diagram showing a first embodiment of a superconducting high-frequency acceleration cavity according to the present invention.

FIG. 2 is a configuration diagram showing a second embodiment of a superconducting high-frequency acceleration cavity according to the present invention.

FIG. 3 is a configuration diagram showing a third embodiment of a superconducting high-frequency acceleration cavity according to the present invention.

FIG. 4 is a configuration diagram showing a fourth embodiment of a superconducting high-frequency acceleration cavity according to the present invention.

FIG. 5 is a configuration diagram showing a fifth embodiment of the superconducting high-frequency acceleration cavity according to the present invention.

FIG. 6 is a configuration diagram showing a conventional superconducting high-frequency accelerating cavity.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Cavity main body 2 Helium reservoir 3 First radiation heat shield 4 Vacuum container 5 High frequency power supply port (input port) 6 Input coupler 7 Beam pipe 8 {O} coupler 9 Piezoelectric element tuner 10 Helium supply port 10a Helium refrigerator 11 Helium reservoir for input coupler 12 Helium supply port for input coupler 12a Helium refrigerator 13 Monitor port 14 Monitor probe 15 OM port 16 General-purpose cryogenic refrigerator 16a Flexible conductor 17 Second radiant heat shield 19 General-purpose cryogenic refrigerator 20 Radiant heat Shield 21 Heat transfer path 23 Heat transfer path

Claims (9)

[Claims] 1. A helium refrigerator, a helium refrigerator for supplying helium to the helium liquid reservoir, and a helium refrigerator for supplying liquid helium to the helium liquid reservoir. A helium supply port for guiding the helium to be supplied to the helium reservoir, a radiant heat shield and a vacuum vessel disposed outside the helium reservoir, a beam pipe connected to both ends of the cavity main body, and the cavity main body A superconducting high-frequency accelerating cavity including an input coupler for supplying high-frequency power to the input coupler, wherein the input port is provided with a helium refrigerator and a helium supply port that are separate from the cavity main body, at a mounting port portion of the input coupler; A superconducting high-frequency accelerating cavity, wherein a cooling system for the cavity main body and the cooling system for the cavity main body are separated. 2. The superconducting high-frequency accelerating cavity according to claim 1, wherein the helium refrigerator and the helium supply port are respectively connected to a harmonic coupler, which is a heat intrusion source other than the input coupler, and other identifiable heat intrusion points. A superconducting high-frequency acceleration cavity characterized by being provided. 3. A helium refrigerator for supplying liquid helium to the helium storage tank, a helium liquid storage tank for bringing the cavity main body to an extremely low temperature state, and a helium refrigerator. A helium supply port for guiding helium to the helium reservoir, a radiant heat shield and a vacuum vessel disposed outside the helium reservoir, a beam pipe connected to both ends of the cavity body, and a high frequency power supply to the cavity body. In the superconducting high-frequency accelerating cavity provided with the input coupler for supplying the heat, the cooling of the input coupler or the cooling of each of the harmonic coupler and other identifiable heat intrusion points which are heat intrusion sources other than the input coupler is performed. A superconducting high-frequency accelerating cavity, wherein the refrigerator is a general-purpose cryogenic refrigerator having two heat stages. 4. The superconducting high-frequency accelerating cavity according to claim 3, wherein the radiant heat shield is a first radiant heat shield having the same temperature as a heat stage on a high temperature side of the general-purpose cryogenic refrigerator. A second radiant heat shield having the same temperature as that of the low-temperature side heat stage of the general-purpose cryogenic refrigerator is provided between the shield and the helium liquid storage tank that houses the cavity body, and the second radiant heat shield uses an input coupler. A superconducting high-frequency accelerating cavity, wherein said superconducting high-frequency accelerating cavity covers a portion and said cavity main body. 5. The superconducting high-frequency accelerating cavity according to claim 3, wherein a general-purpose cryogenic refrigerator having two heat stages is provided, and a high-temperature side of the general-purpose cryogenic refrigerator is provided outside a helium liquid storage tank. A superconducting high-frequency accelerating cavity, provided with a radiant heat shield at the same temperature as the heat stage. 6. A cavity body, a radiant heat shield and a vacuum vessel disposed outside the cavity body, a beam pipe connected to both ends of the cavity body, and supplying high-frequency power to the cavity body. In a superconducting high-frequency accelerating cavity equipped with an input coupler, a plurality of general-purpose cryogenic refrigerators having two stages of heat stages are provided, and the low-temperature side heat stages of these general-purpose cryogenic refrigerators are cavity-connected by a heat transfer path. A superconducting high-frequency accelerating cavity, wherein the main body is connected to an input coupler, a high-frequency coupler as a heat intrusion source other than the input coupler, and other identifiable heat intrusion points. 7. A superconducting high-frequency accelerating cavity according to claim 3, wherein the high-temperature side heat stage is a general-purpose cryogenic refrigerator having a temperature of 80K and a low-temperature side heat stage of 20K. Torso. 8. The superconducting high-frequency accelerating cavity according to claim 5, wherein the high-temperature side heat stage is a general-purpose cryogenic refrigerator having a temperature of 40K and a low-temperature side heat stage of 4K. Torso. 9. A particle accelerator comprising the superconducting high-frequency accelerating cavity according to any one of claims 1 to 8.