阅读说明：本技术 一种紧凑型高频直线加速器系统及其应用 (Compact high-frequency linear accelerator system and application thereof ) 是由 何源 王志军 窦为平 陈伟龙 于 2020-12-30 设计创作，主要内容包括：本发明涉及一种紧凑型高频直线加速器系统及其应用,该系统包括：离子源,用于产生离子束流；直线加速器系统,通过低能传输线与所述离子源连接,用于对离子束流进行加速和传输,以得到不同能量值的加速离子束流；所述直线加速器系统包括射频四极场加速器、交叉指漂移管直线加速器、边耦合漂移管直线加速器和返波型行波加速器；剂量分配系统,与所述返波型行波加速器的输出端连接,用于对不同能量值的加速离子束流进行分离并输送至患病部位,以满足不同癌症治疗的需求。本发明采用局部屏蔽和整体屏蔽相结合的思路,可减小整体屏蔽体的尺寸约1/4,从而减小整个直线加速器系统的安装尺寸。(The invention relates to a compact high-frequency linear accelerator system and application thereof, wherein the system comprises: an ion source for generating an ion beam current; the linear accelerator system is connected with the ion source through a low-energy transmission line and is used for accelerating and transmitting the ion beam current so as to obtain accelerated ion beam currents with different energy values; the linear accelerator system comprises a radio frequency quadrupole field accelerator, an interdigital drift tube linear accelerator, an edge coupling drift tube linear accelerator and a backward wave type traveling wave accelerator; and the dose distribution system is connected with the output end of the backward wave type traveling wave accelerator and is used for separating accelerated ion beam current with different energy values and conveying the accelerated ion beam current to the affected part so as to meet the requirements of treating different cancers. The invention adopts the idea of combining the local shielding and the whole shielding, and can reduce the size of the whole shielding body to about 1/4, thereby reducing the installation size of the whole linear accelerator system.)

1. A compact high frequency linac system, comprising:

an ion source (1) for generating a beam of ions;

the linear accelerator system is connected with the ion source (1) through a low-energy transmission line (2) and is used for accelerating and transmitting ion beam current so as to obtain accelerated ion beam current with different energy values; the linear accelerator system comprises a radio frequency quadrupole field accelerator (3), an interdigital drift tube linear accelerator (4), an edge coupling drift tube linear accelerator (5) and a backward wave type traveling wave accelerator (6);

the input end of the radio frequency quadrupole field accelerator (3) is connected with the output end of the low energy transmission line (2) and is used for accelerating the ion beam output from the low energy transmission line (2);

the input end of the interdigital drift tube linear accelerator (4) is connected with the output end of the radio frequency quadrupole field accelerator (3) and is used for accelerating the ion beam current output from the radio frequency quadrupole field accelerator (3);

the input end of the side-coupled drift tube linear accelerator (5) is connected with the output end of the interdigital drift tube linear accelerator (4) and is used for accelerating the ion beam current output from the interdigital drift tube linear accelerator (4);

the input end of the backward wave type traveling wave accelerator (6) is connected with the output end of the side coupling drift tube linear accelerator (5) and is used for accelerating the ion beam current output from the side coupling drift tube linear accelerator (5);

the shielding system comprises an integral shielding system (11) and a local shielding system, the local shielding system comprises an accelerator shielding system (9) and a high-energy transmission line shielding system (10), the integral shielding system is used for shielding generated secondary particles so that the dosage level outside the shielding system meets the personal safety requirement, the local shielding system is used for enabling components in the tunnel to be small in radiation damage and long in service life, and the waiting time for entering of maintenance personnel after stopping can be shortened.

2. The compact high frequency linear accelerator system according to claim 1, wherein the focusing element of at least one of the interdigital drift tube linear accelerator (4), the edge-coupled drift tube linear accelerator (5) and the backward-wave traveling wave accelerator (6) is a variable gradient permanent magnet comprising two concentric rings on which permanent magnetic material is distributed, and the outer ring of the concentric rings is sleeved with a metal sleeve.

3. The compact high frequency linac system according to claim 2, characterized in that the gradient range of the variable gradient permanent magnet is 140-.

4. The compact high frequency linear accelerator system of claim 1, wherein the shielding material of the local shielding system is a metal that is not easily activated, a hydrogen containing material, concrete or heavy concrete; the shielding material of the integral shielding system (11) is concrete or heavy concrete.

5. The compact high frequency linear accelerator system of claim 4, wherein the non-easily activated metal comprises lead and lead alloys, tungsten and tungsten alloys, iron and iron alloys, or aluminum and aluminum alloys.

6. The compact high frequency linac system according to claim 4, wherein the hydrogen-containing material comprises water, heavy water, polyethylene, or boron-containing polyethylene.

7. The compact high frequency linac system according to claim 1, which is capable of simultaneously satisfying the transport requirements for particles having a nuclear to mass ratio of 1/2 or more.

8. Use of a compact high frequency linac system according to any of claims 1 to 7 in FLASH methods of ion radiotherapy, cancer therapy and cosmetology.

Technical Field

The invention relates to a compact high-frequency linear accelerator system and application thereof, belonging to the technical field of medical equipment.

Background

Compared with the traditional cancer radiotherapy, the proton and heavy ion technology has great advantages, ions are accelerated to a specific energy range through an accelerator, ion rays are formed and are led out to be emitted into a human body, a Bragg curve-shaped energy release track is formed, powerful irradiation can be carried out on tumors, irradiation on surrounding normal tissues is greatly reduced, and the maximum curative effect is achieved. The ion energy required for treatment varies according to the tumor location, and the energy range is generally from 70 to 230 MeV/u.

Proton treatment accelerators typically employ proton cyclotrons and synchrotrons, while heavy ion accelerators typically employ synchrotrons. The cyclotron can provide continuous and stable beams, but the cyclotron is a weak focusing structure, has low transmission efficiency, can bring about more serious activation problems, and the energy of the extracted beams is fixed.

The synchrotron can realize energy adjustment, but the injection, energy rise and standard circulation of the synchrotron takes a long time, the transduction time is about the second level, the ineffective treatment time can be increased, and the synchrotron can only provide pulse beam, and the induced beam has low flow and average flow strength and cannot adapt to the requirements of quick and continuous treatment. In addition, the synchrotron occupies a large area, and the whole system architecture is complex.

The linear accelerator has the main advantages of small transverse size, easy extraction and injection, almost no beam loss in the transmission and acceleration processes, and adjustable energy. However, the conventional linear accelerator includes a focusing system for transverse confinement, a resonant cavity for longitudinal acceleration, and a long matching transmission line between different types of acceleration structures, so the longitudinal dimension is too long to meet the installation requirements of hospitals.

Disclosure of Invention

Aiming at the outstanding problems, the invention provides a compact high-frequency linear accelerator system suitable for hospital installation scale and application thereof, the longitudinal length of the linear accelerator system is less than 25m, the loss beam power is low, the shielding system is safe and simple, the transmission of particles with the nuclear-to-mass ratio of greater than or equal to 1/2 can be met, and the beam can be supplied to a plurality of terminals with different energies.

In order to achieve the purpose, the invention adopts the following technical scheme:

a compact high frequency linac system, comprising:

an ion source for generating an ion beam current;

the linear accelerator system is connected with the ion source through a low-energy transmission line and is used for accelerating and transmitting the ion beam current so as to obtain accelerated ion beam currents with different energy values; the linear accelerator system comprises a radio frequency quadrupole field accelerator, an interdigital drift tube linear accelerator, an edge coupling drift tube linear accelerator and a backward wave type traveling wave accelerator;

the input end of the radio frequency quadrupole field accelerator is connected with the output end of the low energy transmission line and is used for accelerating the ion beam current output from the low energy transmission line;

the input end of the interdigital drift tube linear accelerator is connected with the output end of the radio frequency quadrupole field accelerator and is used for accelerating the ion beam current output from the radio frequency quadrupole field accelerator;

the input end of the side coupling drift tube linear accelerator is connected with the output end of the interdigital drift tube linear accelerator and is used for accelerating the ion beam current output by the interdigital drift tube linear accelerator;

the input end of the backward wave type traveling wave accelerator is connected with the output end of the side coupling drift tube linear accelerator and is used for accelerating the ion beam current output by the side coupling drift tube linear accelerator;

the shielding system comprises an integral shielding system and a local shielding system, wherein the local shielding system comprises an accelerator shielding system and a high-energy transmission line shielding system, the local shielding system enables the radiation damage of components in the tunnel to be small, the service life of the components is long, in addition, the waiting time for the approach of maintenance personnel after the shutdown can be shortened, and the integral shielding system enables the dosage level outside the shielding system to meet the personal safety requirement.

Preferably, the focusing component of at least one of the interdigital drift tube linear accelerator, the edge-coupled drift tube linear accelerator and the backward wave type traveling wave accelerator is a variable gradient permanent magnet, and the focusing component comprises two concentric rings, permanent magnet materials are distributed on the concentric rings, and metal sleeves are sleeved outside the concentric rings.

In the compact high-frequency linear accelerator system, the gradient range of the variable gradient permanent magnet is preferably 140-.

The compact high-frequency linear accelerator system is characterized in that the shielding material of the local shielding system is preferably metal, hydrogen-containing material, concrete or heavy concrete which is not easy to activate; the shielding material of the integral shielding system is concrete or heavy concrete.

In the compact high-frequency linear accelerator system, preferably, the metal which is not easy to activate comprises lead and lead alloy, tungsten and tungsten alloy, iron and iron alloy or aluminum and aluminum alloy.

In the compact high-frequency linear accelerator system, preferably, the hydrogen-containing material includes water, heavy water, polyethylene or boron-containing polyethylene.

The compact high-frequency linear accelerator system preferably further comprises a dose distribution system connected with the output end of the backward wave type traveling wave accelerator and used for separating accelerated ion beams with different energy values and conveying the accelerated ion beams to affected parts; the dose distribution system comprises a multi-channel secondary iron and a plurality of high-energy transmission lines, the multi-channel secondary iron is used for separating ion beams with different energy values, the high-energy transmission lines are used for transmitting the accelerated ion beams to diseased parts of different cancer patients, and the high-energy transmission lines deviate from the center of an upstream linear accelerator, so that accelerator activation caused by recoil neutrons generated during beam debugging is avoided.

The compact high-frequency linear accelerator system is preferably characterized in that the radio-frequency quadrupole field accelerator, the interdigital drift tube linear accelerator, the edge-coupled drift tube linear accelerator and the backward wave type traveling wave accelerator are respectively provided with a radio-frequency power source, a feeding system and a low-level control system which are independent of each other.

The compact high-frequency linear accelerator system can meet the transmission requirement of particles with the nuclear-to-mass ratio of 1/2 or more.

The invention also provides an application of the compact high-frequency linear accelerator system in a FLASH method and cosmetology of ion radiotherapy and cancer treatment.

Due to the adoption of the technical scheme, the invention has the following advantages:

1. the linear accelerator cavity has high acceleration gradient, particularly a backward wave type traveling wave accelerator, the effective acceleration gradient can reach 60MV/m, and the compact transmission line is used for replacing the existing longer matching transmission line, so that the longitudinal length of the whole linear accelerator system is less than 25m, and the requirement of the hospital on installation length is met;

2. the beam loss control is carried out through the radio frequency quadrupole field accelerator, so that the beam loss mainly occurs at the RFQ accelerator and the interdigital drift tube linear accelerator, and according to the characteristics of the beam loss, the local shielding is added at the position, so that the radiation damage of components in the tunnel is small, the service life is long, and in addition, the waiting time for entering the tunnel by maintenance personnel after stopping can be shortened. By adopting the concept of combining the local shielding and the integral shielding, the size of the integral shielding body can be reduced by about 1/4, so that the installation size of the whole linear accelerator system is reduced;

3. the linear accelerator system can meet the transportation requirement of particles with the nuclear-mass ratio of 1/2 or more by using the permanent magnet with variable gradient to replace the existing permanent magnet with invariable gradient.

Drawings

FIG. 1 is a block diagram of a compact high frequency linear accelerator system according to an embodiment of the invention;

FIG. 2 is a block diagram of an edge-coupled drift tube linear accelerator according to an embodiment of the present invention;

FIG. 3 is a schematic view of a variable gradient permanent magnet according to this embodiment of the present invention;

FIG. 4 is a schematic perspective view of a backward wave type traveling wave accelerator according to the embodiment of the present invention;

the respective symbols in the figure are as follows:

1-an ion source; 2-a low energy transmission line; 3-a radio frequency quadrupole field accelerator; 4-interdigital drift tube linear accelerators; 5-side coupling drift tube linear accelerator, 51-accelerating cavity, 52-coupling cavity, 53-side coupling drift tube and 54-permanent magnet; 6-a backward wave type traveling wave accelerator, 61-a drift tube, 62-a magnetic coupling hole and 63-a disk; 7-multichannel secondary iron; 8-high energy transmission line; 9-accelerator shield system; 10-high energy transmission line shielding system; 11-integral shielding system.

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention more apparent, the technical solutions of the present invention are described clearly and completely below, and it is obvious that the described embodiments are some, not all embodiments of the present invention. All other embodiments, which can be obtained by a person skilled in the art without any inventive step based on the embodiments of the present invention, are within the scope of the present invention.

Fig. 1 is a block diagram of a compact high-frequency linear accelerator system according to an embodiment of the present invention. As shown in fig. 1, the system includes: the ion source 1 is used for generating ion beam current, and the linear accelerator system is connected with the ion source 1 through a low-energy transmission line 2 and is used for accelerating and transmitting the ion beam current so as to obtain accelerated ion beam currents with different energy values; and the dose distribution system is connected with the linear accelerator system and is used for separating accelerated ion beam current with different energy values and conveying the accelerated ion beam current to the affected part so as to meet the requirements of different cancer treatments.

In this embodiment, the ion source 1 is preferably an Electron Cyclotron Resonance (ECR) ion source or a laser ion source for generating an ion beam, the beam energy at the outlet of the ion source 1 is in the range of 20 to 25keV/u, and the operating frequency of the ECR ion source is preferably 18 GHz.

In this embodiment, the low-energy transmission line 2 is configured to receive an ion beam output by the ion source 1 and having a nuclear-to-mass ratio greater than or equal to 1/2, and match the ion beam and send the ion beam to a Radio Frequency Quadrupole (RFQ) accelerator 3.

In this embodiment, the linear accelerator system includes: the system comprises a radio frequency quadrupole field accelerator 3, an interdigital drift tube linear accelerator 4, an edge coupling drift tube linear accelerator 5 and a backward wave type traveling wave accelerator 6 which are connected in sequence; the dose distribution system comprises a multi-channel secondary iron 7 and a plurality of high-energy transmission lines 8, wherein the multi-channel secondary iron 7 is used for separating ion beam current with different energy values, and the high-energy transmission lines 8 are used for transmitting the accelerated ion beam current to diseased parts of different cancer patients.

The radio frequency quadrupole field accelerator 3 is used for accelerating the beam output from the low-energy transmission line 2 to specific energy, the working frequency range of the radio frequency quadrupole field accelerator 3 is preferably between 714MHz and 750MHz, and the outlet energy range is 2-3 MeV/u. Compared with a conventional RFQ accelerator, the radio frequency quadrupole field accelerator 3 is structurally improved (the specific structure is disclosed in the Chinese patent with the publication number of CN110267426A, which is not described herein), can realize separation of a central beam cluster and low-energy particles after acceleration, reduce beam loss power, and reduce space dose and equipment activation risk.

The transverse matching between the tail end of the radio frequency quadrupole field accelerator 3 and the front accelerating units and the gathering units of the interdigital drift tube linear accelerator 4 is completed, the matching function of a commonly used medium-energy transmission line is replaced, and the length of the whole linear accelerator can be shortened by about 2-3 meters. The transverse matching is completed by gradually increasing the radius of the tail end of the radio frequency quadrupole field accelerator 3, and adjusting the length of the tail end unit and the gradient of the quadrupole iron. The radius of the tail end of a common radio frequency quadrupole field accelerator 3 is kept constant, and the transverse focusing is too large, while the transverse focusing of an interdigital drift tube linear accelerator 4 is relatively weak, so that the transverse matching is difficult to realize. When the radius of the tail end of the radio frequency quadrupole field accelerator 3 is gradually increased, the transverse focusing of the radio frequency quadrupole field accelerator is gradually weakened until the transverse focusing is equivalent to that of the interdigital drift tube linear accelerator 4, and the difficulty of transverse matching is reduced. Further, the length of the tail end unit of the radio frequency quadrupole field accelerator 3 is optimally selected, 360-degree rotation of a beam phase space can be achieved, and further matching with the interdigital drift tube linear accelerator 4 is achieved.

In the linear accelerator system, a radio frequency quadrupole field accelerator 3 and an interdigital drift tube linear accelerator 4 are low-energy acceleration sections, a side-coupled drift tube linear accelerator 5 is an intermediate-energy acceleration section, a backward wave type traveling wave accelerator 6 is a high-energy acceleration section, and the accelerators are connected in series to accelerate ion beams to specific energy meeting the requirements of patients. The interdigital drift tube linear accelerator 4 can accelerate the beam to a plurality of MeV energy sections, has the highest shunt impedance, and can continuously accelerate the beam at the outlet of the radio frequency quadrupole field accelerator 3 to specific energy. The operating frequency range of the radio frequency quadrupole field accelerator 3 and the interdigital drift tube linear accelerator 4 is between 714MHz and 750 MHz. The side-coupled drift tube linear accelerator 5 can accelerate the beam to tens of MeV energy sections, has high shunt resistance, and is used for continuously accelerating the beam at the outlet of the interdigital drift tube linear accelerator 4 to specific energy. The backward wave type traveling wave accelerator 6 is used for accelerating the beam current at the outlet of the side-coupled drift tube linear accelerator 5 to 70-230 MeV/u. The working frequency ranges of the side-coupled drift tube linear accelerator 5 and the backward wave type traveling wave accelerator 6 are between 2856MHz and 3000 MHz.

The interdigital drift tube linear accelerator 4 preferably has an operating frequency range between 714MHz and 750MHz and an outlet energy range of 7-10 MeV/u. The addition of the interdigital drift tube linear accelerator 4 between the radio frequency quadrupole field accelerator 3 and the edge-coupled drift tube linear accelerator 5 is necessary to replace the existing scheme, and has two obvious advantages. On the one hand, the 750MHz radio frequency quadrupole field accelerator 3 and the 3GHz side coupling drift tube linear accelerator 5 have frequency hopping, the loss of beam current may be brought by the frequency hopping, and the low energy frequency hopping increases the risk of loss. On the other hand, compared with the side-coupled drift tube linear accelerator 5, the interdigital drift tube linear accelerator 4 can increase the beam energy from 2-3MeV/u to 7-10MeV/u, the effective acceleration gradient can be increased by about 4-5 times, and the length of the whole system is shortened to 1/4-1/5. In addition, the interdigital drift tube linear accelerator 4 can also bear beam loss, low-energy particles which are output by the radio frequency quadrupole field accelerator 3 and do not meet the acceleration requirement of the interdigital drift tube linear accelerator 4 can be lost at the position, the accelerator local shielding system 9 is designed in a targeted manner, the radiation damage of components in a tunnel can be small, the service life is long, the waiting time for entering the tunnel of maintenance personnel after stopping can be shortened, the size (length and thickness) of the whole shielding system 11 can be reduced, the idea of combining local shielding and whole shielding is adopted, the size of the whole shielding system can be reduced by about 1/4, the safety of the shielding system is ensured, and the installation size and cost of the shielding system can be reduced. The local shielding system 9 or 10 is made of metal which is not easy to activate, hydrogen-containing material, concrete or heavy concrete. And the integral shielding system 11 is made of concrete or heavy concrete.

The working frequency range of the edge-coupled drift tube linear accelerator 5 is preferably between 2856MH and 3000MHz, and the outlet energy range is 60-80 MeV/u. As shown in fig. 2, a preferred embodiment of an edge-coupled linac structure is shown. The device is formed by connecting a series of side-coupled drift tube acceleration modules in series. An edge-coupled drift tube acceleration module comprises an acceleration cavity 51, a coupling cavity 52, an edge-coupled drift tube 53, and an acceleration gap between the drift tubes. The edge-coupled drift tube 53 is connected to the accelerating cavity 51 by a support structure. The working mode of the acceleration cavity 51 is 0 mode, the beam obtains energy gain when passing through the gap between the side coupling drift tubes 53, and when the electric field is reversed, the beam enters the side coupling drift tubes 53 and can be shielded. Two adjacent accelerating cavities 51 are connected by a vacuum pipe (not shown). The working mode of the accelerating cavity 51 is pi mode, and the accelerating efficiency is higher. A permanent magnet 54 is disposed between two adjacent accelerating cavities 51 for laterally focusing the beam current. The number of acceleration gaps in one acceleration chamber 51 may be increased gradually, up to 10-14, as the beam energy increases.

In the embodiment, preferably, the variable gradient permanent magnet is adopted to replace the constant gradient permanent magnet which is commonly used at present, and the linear accelerator system can meet the transportation requirement of particles with the nuclear-mass ratio of greater than or equal to 1/2. As shown in FIG. 3, a schematic diagram of a preferred embodiment of a variable gradient permanent magnet is shown. The gradient variable permanent magnet consists of two concentric rings, flaky permanent magnetic materials are distributed on the rings and are bonded with each other, the whole concentric rings are arranged in a metal sleeve with the same shape, and each ring can independently generate a concentrated quadrupole field. When the arrangement direction angles of the magnetic materials of the two concentric rings are the same, the intensity of the collecting quadrupole field reaches the maximum value, when the arrangement direction angles of the magnetic materials of the two concentric rings are opposite, the intensity of the collecting quadrupole field reaches the minimum value, and the relative angle theta is changed to theta 1+ theta 2, so that the gradient of the collecting quadrupole field is between the maximum value and the minimum value. The gradient range of the variable gradient permanent magnet of a preferred embodiment is 140-280T/m, and the focusing requirement of particles with the nuclear-to-mass ratio of 1/2 or more is met.

As shown in fig. 4, a schematic structural diagram of a preferred backward type traveling wave accelerator 6 according to an embodiment of the present invention is shown, and the operating frequency range of the accelerator is preferably between 2856MHz and 3000MHz, and the accelerator is formed by connecting a series of backward type traveling wave acceleration modules in series, where one backward type traveling wave acceleration module includes a drift tube 61, a magnetic coupling hole 62 and a disk 63. The disks 63 are arranged in one-to-one correspondence with the drift tubes 61 and used for fixing the drift tubes 61 on the backward wave type traveling wave accelerator 6, and the disks 63 are provided with magnetic coupling holes 62.

The conventional proton linear accelerator generally adopts a dual-period standing wave acceleration structure in a high-energy section, and compared with the conventional dual-period standing wave acceleration structure, the return wave type traveling wave accelerator has the advantages of short field building time, small reflected power, adjustable energy and the like.

In the prior art, a traveling wave accelerator is considered to replace a double-period standing wave acceleration structure, the double-period standing wave acceleration structure has the characteristics of adjustable energy, high acceleration gradient and the like, the effective shunt impedance can reach 55M omega/M, and the structure of the traveling wave accelerator is the existing forward traveling wave acceleration structure of a disk-load waveguide. Compared with the existing disc-loaded waveguide forward traveling wave acceleration structure, the preferred backward traveling wave accelerator in the specific implementation mode of the invention has the characteristics of higher effective shunt impedance, higher energy gain and the like. The existing disk charge waveguide forward traveling wave accelerating structure adopts a central hole for electric coupling, which can be understood as that a hole is formed in the middle of the disk 63, and the diameter of the central hole is required to be relatively large in order to increase the coupling. The wave returning type traveling wave accelerator 6 of the invention is additionally provided with the magnetic coupling hole 62 on the disk 63 and works in a magnetic coupling mode, so that the beam central hole can be made very small, in addition, the wave returning type traveling wave accelerator 6 of the invention is also additionally provided with the drift tube 61, an electric field is more concentrated between two adjacent drift tubes, the shunt impedance is improved by about one time, the effective shunt impedance can be more than 100M omega/M, and the effective acceleration gradient can reach 60 MV/M.

In this embodiment, the rf quadrupole accelerator 3, the interdigital drift tube linear accelerator 4, the edge-coupled drift tube linear accelerator 5, and the backward wave type traveling wave accelerator 6 are respectively provided with an rf power source, a feeding system, and a low level control system (not shown). The radio frequency power source provides radio frequency power for each accelerator; the feeding system is used for feeding the radio frequency power emitted from the radio frequency power source into each accelerator; the low-level control system is used for adjusting the radio frequency power and the phase. Preferably, the radio frequency power source adopts a klystron or a gyrotron, and the low level control system adopts digital low level.

In this embodiment, the high energy transmission lines 8 are used to transmit beams of specific energies to the terminals. The multi-channel dipolar iron 7 can realize the separation of a plurality of specific energy beam flows and is transmitted to different energy terminals through a plurality of high-energy transmission lines 8, so that the beam supply of different energy terminals is realized. The high-energy transmission line 8 has a large energy acceptance, and when the energy demand changes, other energy spot-beam streams can be transmitted to the terminal through the fine adjustment of the current of the multi-channel diode 7.

The compact high-frequency linear accelerator can provide ion beam current with peak current intensity of a plurality of emA to more than ten emA at the highest peak value within us time, and the duty ratio can reach 4 per thousand at the highest. For conventional ion cancer treatment, cancer cells are killed by accumulating the mainly passed dose, so that the strong mean flow which is tens of nA can meet the requirements, and the compact high-frequency linear accelerator disclosed by the invention is very easy to realize. For ion FLASH cancer treatment, cancer cells are rendered dead by hypoxia mainly through transient ultra-high dose, so that mainly concerning dose rate, the compact high-frequency linear accelerator of the invention can be 5 x 5cm at the target²Providing doses in the range of thousands of Gy/s, FLASH cancer treatment can be completed in a shorter time, even on the ms scale.

The compact high-frequency linear accelerator of the invention canSimultaneously, the acceleration and the transmission of particles with nuclear-to-proton ratio of 1/2 or more are satisfied, so that ions with different energies and different ion numbers can be provided, for example, 22MeV protons, 41MeV/u¹²C⁶⁺22MeV/u⁴He²⁺25MeV/u of⁷Li³⁺And the like, these ions are widely used in the cosmetic industry.

Finally, it should be noted that: the above examples are only intended to illustrate the technical solution of the present invention, but not to limit it; although the present invention has been described in detail with reference to the foregoing embodiments, it will be understood by those of ordinary skill in the art that: the technical solutions described in the foregoing embodiments may still be modified, or some technical features may be equivalently replaced; and such modifications or substitutions do not depart from the spirit and scope of the corresponding technical solutions of the embodiments of the present invention.