Medical superconducting particle linear accelerator

Abstract

The invention relates to a medical superconducting particle linear accelerator which comprises an injector, a superconducting short acceleration mechanism and a superconducting edge coupling acceleration cavity. The superconducting short acceleration mechanism is then connected in series with the superconducting edge coupling acceleration cavity, and particles generated by the injector sequentially pass through the superconducting short acceleration mechanism and the superconducting edge coupling acceleration cavity; each superconducting short acceleration mechanism and each superconducting edge coupling acceleration cavity are provided with a superconducting klystron high-frequency power source; and the liquid helium preparation and compensation mechanism provides a liquid helium refrigeration working medium. According to the medical superconducting particle linear accelerator, the injector, the short acceleration mechanisms and the side coupling acceleration cavities are connected in series to form the medical superconducting particle linear accelerator, a high-frequency power source with a small size is configured for each acceleration unit, all the acceleration units and the high-frequency power sources are superconductive, and therefore the formed superconducting particle linear accelerator has the advantages that the medical superconducting particle linear accelerator is simple in structure and low in cost. The energy consumption is low, the operation cost is low, and radiation therapy is supported.

Description

Technical Field

[0001] This invention relates to the field of medical superconducting particle linear accelerators. Background Technology

[0002] Linear particle accelerators offer advantages such as convenient beam injection and extraction, and high beam intensity, but also suffer from high energy consumption. While high energy consumption isn't a significant operational cost issue for scientific experiments, it becomes prohibitive for radiotherapy. The high energy consumption of linear particle accelerators stems primarily from two sources: the energy consumed in establishing the high-frequency electric field within the accelerating cavity, and the energy consumed by the high-frequency power source itself. An effective way to reduce energy consumption is to achieve superconductivity, and the key to achieving superconductivity lies in the miniaturization of the accelerating mechanism and the high-frequency power source, which necessitates changes to the typical layout of linear particle accelerators. For radiotherapy, linear particle accelerators require accelerated particles to reach high energies, such as 230 MeV / u for protons and 420 MeV / u for carbon ions. Linear particle accelerators at these energy levels typically consist of two accelerating sections: a low-energy section and a high-energy section. The low-energy section generally uses several Alvarez (LW) accelerating cavities, while the high-energy section typically uses several side-coupled accelerating cavities. The diameter of the side-coupled accelerating cavity is about 100 mm, which is convenient for achieving superconductivity, while the diameter of the Alvarez accelerating cavity is between 800 and 1000 mm and the length is between 7 and 16 m. The volume is large and it is not convenient for achieving superconductivity. Summary of the Invention

[0003] This invention addresses the issue that current superconducting particle linear accelerators typically use Alvarez accelerator cavities in series for the low-energy acceleration section, but the Alvarez accelerator cavities themselves are very large and inconvenient to achieve superconductivity. The invention provides a medical superconducting particle linear accelerator that replaces the Alvarez accelerator cavities with a shorter, smaller acceleration mechanism.

[0004] The technical solution adopted by this invention to achieve its technical objective is as follows: a medical superconducting particle linear accelerator, including an injector; further including a set of superconducting short acceleration mechanisms and a set of superconducting side-coupled acceleration cavities; all the superconducting short acceleration mechanisms are then connected in series with all the superconducting side-coupled acceleration cavities, and the particles generated by the injector pass sequentially through the superconducting short acceleration mechanisms and the superconducting side-coupled acceleration cavities; each superconducting short acceleration mechanism and each superconducting side-coupled acceleration cavity is equipped with a superconducting klystron high-frequency power source;

[0005] The liquid helium production and compensation mechanism provides liquid helium refrigerant to all superconducting short acceleration mechanisms, superconducting side-coupled acceleration cavities, and superconducting klystron high-frequency power sources through a series-connected and parallel combined liquid helium injection pipeline.

[0006] Furthermore, the aforementioned medical superconducting particle linear accelerator also includes a vacuum pipe A that runs through all the superconducting short acceleration mechanisms and the superconducting side-coupled acceleration cavity, and the particles generated by the injector are accelerated in the vacuum pipe A.

[0007] Furthermore, in the aforementioned medical superconducting particle linear accelerator: the liquid helium injection pipe is surrounded by a vacuum pipe B.

[0008] In this invention, the medical superconducting particle linear accelerator is composed of an injector connected in series with multiple short acceleration mechanisms and multiple side-coupled acceleration cavities. Each acceleration unit is equipped with a small-volume high-frequency power source, and all acceleration units and tube high-frequency power sources are made superconducting. The superconducting particle linear accelerator composed of this method can support radiotherapy with lower energy consumption and thus lower operating costs.

[0009] The present invention will now be described in detail with reference to the accompanying drawings and specific embodiments. Attached Figure Description

[0010] Appendix Figure 1 This is a layout diagram of the medical superconducting particle linear accelerator of the present invention. Detailed Implementation

[0011] This embodiment is a medical superconducting particle linear accelerator consisting of an injector 1, several superconducting short acceleration mechanisms 2, and several superconducting side-coupled acceleration cavities 3 connected in series. A vacuum pipe A4 connects the injector 1 and runs through all the superconducting short acceleration mechanisms 2 and superconducting side-coupled acceleration cavities 3. Each superconducting short acceleration mechanism 2 and superconducting side-coupled acceleration cavity 3 is equipped with a superconducting klystron high-frequency power source 5. A liquid helium production and compensation mechanism 6 provides liquid helium refrigerant to all the superconducting short acceleration mechanisms 2, superconducting side-coupled acceleration cavities 3, and superconducting klystron high-frequency power sources 5 through a series-parallel combined liquid helium injection pipe. The liquid helium injection pipe is surrounded by a vacuum pipe B7.

[0012] In this embodiment, the particles ejected from the injector 1 are accelerated in the vacuum pipe A4. The acceleration is mainly achieved by connecting several superconducting short acceleration mechanisms 2 and several superconducting side-coupled acceleration cavities 3 in series to form an acceleration channel.

[0013] In this embodiment, the injector 1 adopts the most commonly used injector, which includes an ion source and a primary acceleration mechanism, and typically comes in three styles:

[0014] 1. Connect the ion source to a high voltage multiplier, and then connect it to a beam mixer;

[0015] 2. Connect the ion source to a single-stage electrostatic accelerator or a tandem electrostatic accelerator, and then connect it to a beam mixer;

[0016] 3. Connect the ion source to a high-energy quadrupole field (RFQ) accelerator. Since the RFQ also has the function of focusing, there is no need to provide a separate focuser.

[0017] Figure 1 The injector 1 shown uses an ion source connected to an RFQ, which are integrated into one unit.

[0018] There are various options for the superconducting short acceleration mechanism 2, such as a single-gap acceleration cavity, a short cylindrical helical cavity, a planar helical cavity, a split-ring acceleration cavity, a λ / 4 resonant cavity, and a multi-unit elliptical cavity. These short acceleration mechanisms are all convenient for achieving superconductivity. In this embodiment, the superconducting short acceleration mechanism 2 uses a superconducting single-gap acceleration cavity.

[0019] A continuous particle beam is generated by an ion source, accelerated by a primary acceleration mechanism to obtain a certain energy, focused by a beam gatherer to form a pulsed beam with a frequency, accelerated by multiple short acceleration mechanisms in a low-energy acceleration section to reach the energy required for the connecting side-coupled acceleration cavity, and then accelerated by multiple side-coupled acceleration cavities to reach the energy required for radiotherapy.

[0020] In this embodiment, the phase of each superconducting short acceleration mechanism 2 is independently adjustable, so the spacing is not limited.

[0021] Different particles have different charge-to-mass ratios, and the energy required to connect and couple the accelerating cavity also varies. For protons, this energy is above 100 MeV.

[0022] The number of superconducting short acceleration mechanisms 2 depends on the acceleration voltage of a single short acceleration mechanism. Generally, the number of short acceleration mechanisms can reach dozens or even hundreds.

[0023] The number of superconducting side-coupled accelerating cavities 3 depends on the number of accelerating cavities in each superconducting side-coupled accelerating cavity 3 and the energy gain of each accelerating cavity. Generally, a dozen or so superconducting side-coupled accelerating cavities 3 are required.

[0024] In this embodiment, although only six superconducting short acceleration mechanisms 2 and three superconducting side-coupled acceleration cavities 3 are arranged, the layout of the accelerator can be demonstrated.

[0025] As shown in the figure Figure 1 The focusing equipment, guiding equipment, various beam testing equipment and vacuum equipment necessary for a linear accelerator are omitted, but this does not affect the presentation of the basic features of this invention: the series combination of multiple superconducting short acceleration mechanisms 2 in the low-energy acceleration section and multiple superconducting side-coupled acceleration cavities 3 in the high-energy acceleration section.

Claims

1. A medical superconducting particle linear accelerator, comprising an injector (1); characterized in that: It also includes a set of superconducting short acceleration mechanisms (2) and a set of superconducting side-coupled acceleration cavities (3); all the superconducting short acceleration mechanisms (2) are then connected in series with all the superconducting side-coupled acceleration cavities (3), and the particles generated by the injector (1) pass through the superconducting short acceleration mechanism (2) and the superconducting side-coupled acceleration cavity (3) in sequence; each superconducting short acceleration mechanism (2) and superconducting side-coupled acceleration cavity (3) is equipped with a superconducting klystron high-frequency power source (5); The liquid helium production and compensation mechanism (6) provides liquid helium refrigerant to all superconducting short acceleration mechanisms (2), superconducting side-coupled acceleration cavities (3) and superconducting klystron high-frequency power sources (5) through a series-parallel combination of liquid helium injection pipelines.

2. The medical superconducting particle linear accelerator according to claim 1, characterized in that: It also includes a vacuum pipe A (4) that runs through all the superconducting short acceleration mechanisms (2) and the superconducting side-coupled acceleration cavity (3), in which the particles generated by the injector (1) are accelerated.

3. The medical superconducting particle linear accelerator according to claim 1 or 2, characterized in that: The liquid helium injection pipe is fitted with a vacuum pipe B (7).

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