Accelerator beam space charge compensation measurement device and method

Abstract

The application discloses a kind of space charge compensation degree measuring device and measuring method, it is related to accelerator technical field, including detachable electrode, one end of the detachable electrode is fixedly connected with first diagnostic mechanism, the other end is fixedly connected with second diagnostic mechanism, one end of the first diagnostic mechanism is fixedly connected with one end of the solenoid magnet, the other end of the solenoid magnet is fixedly connected with the ion source;The first diagnostic mechanism is used to measure the beam emittance and beam intensity of the detachable electrode entrance end, and the second diagnostic mechanism is used to measure the beam emittance and beam intensity at the outlet of the detachable electrode.The application provides a kind of space charge compensation degree measuring device, to measure and analyze the space charge compensation degree in the design stage of accelerator, provides the space charge compensation degree measuring method for the design of accelerator, can support the design of accelerator to improve reliability.

Description

Technical Field

[0001] This invention relates to the field of accelerator technology, and specifically to a method for measuring the degree of space charge compensation. Background Technology

[0002] Accelerators have high requirements for the quality of the beam itself and the transmission of the beam, but the space charge effect can affect the beam quality and reduce the transmission efficiency, especially for low-energy high-current ion beams, where the effect of the space charge is more significant.

[0003] However, a space charge compensation mechanism exists in the actual beam transmission process. The principle of this mechanism is that the ion beam will undergo an ionization reaction with the neutral gas remaining in the beam channel, producing secondary electrons and secondary ions. Among them, particles with the same charge as the ion beam will be repelled outward under the influence of the space potential generated by the ion beam, while particles with opposite charges will be constrained by the space potential, thereby neutralizing part of the space charge of the main ion beam to achieve a certain degree of space charge compensation.

[0004] The degree of space charge compensation is affected by the vacuum level. At higher vacuum levels, the number of residual neutral gas particles in the beam channel is smaller, resulting in a lower degree of space charge compensation for the main beam. As the vacuum level decreases, the degree of space charge compensation from the residual gas increases. However, the lower the vacuum level, the higher the collision cross-section between the main beam and residual gas molecules, leading to increased particle loss from collisions in the main beam—a phenomenon known as vacuum stripping loss. Therefore, for accelerators, the vacuum level needs to be maintained within a reasonable range to avoid excessive space charge effects or collision losses, which could result in low beam transmission efficiency.

[0005] During the accelerator design phase, beam dynamics analysis is required to verify the feasibility of the proposed scheme. The space charge effect significantly impacts beam transmission. This is particularly true for the axial injection system design of cyclotron accelerators. Because the injection system is close to the ion source, unreacted gas particles from the ion source migrate into the injection system, resulting in a lower vacuum level compared to other locations and thus a higher degree of space charge compensation. To increase the reliability of the injection system design, the degree of space charge compensation needs to be measured and analyzed. Summary of the Invention

[0006] The purpose of this invention is to provide a device for measuring the degree of space charge compensation, so as to measure and analyze the degree of space charge compensation during the design phase of accelerators, and to provide a method for measuring the degree of space charge compensation in accelerator design, thereby supporting the reliability of accelerator design. Specifically, it includes the following technical solutions:

[0007] An accelerator beam space charge compensation measurement device includes a detachable electrode. One end of the detachable electrode is fixedly connected to a first diagnostic mechanism, and the other end is fixedly connected to a second diagnostic mechanism. One end of the first diagnostic mechanism is fixedly connected to one end of a solenoid magnet, and the other end of the solenoid magnet is fixedly connected to an ion source. The first diagnostic mechanism is used to measure the emittance and beam intensity at the ion inlet end of the detachable electrode, and the second diagnostic mechanism is used to measure the beam emittance and beam intensity at the outlet end of the detachable electrode.

[0008] The first diagnostic device includes a first vacuum chamber, a first emissivity scanner, and a first Faraday cylinder. One end of the first vacuum chamber is fixedly connected to the outlet of the detachable electrode, and the other end is fixedly connected to the solenoid magnet. The first emissivity scanner and the first Faraday cylinder are both mounted on the first vacuum chamber, and the first emissivity scanner and the first Faraday cylinder are arranged parallel to each other.

[0009] The second diagnostic device includes a second vacuum chamber, a second emissivity scanner, and a second Faraday cylinder. One end of the second vacuum chamber is fixedly connected to the outlet end of the detachable electrode, and the other end is fixedly connected to the second Faraday cylinder. The second emissivity scanner is mounted on the second vacuum chamber and is perpendicular to the second Faraday cylinder.

[0010] An accelerator beam space charge compensation measurement device further includes a first DC current transformer and a second DC current transformer. One end of the first DC current transformer is fixedly connected to the outlet end of the first vacuum chamber, and the other end is fixedly connected to the inlet end of the detachable electrode. One end of the second DC current transformer is fixedly connected to the outlet end of the detachable electrolyzer, and the other end is fixedly connected to the inlet end of the second vacuum chamber.

[0011] The detachable electrode includes several electrode assemblies connected end to end in sequence; each electrode assembly includes a housing, inside which is provided a cylindrical electrode, which is fixedly connected to one end of an electrode post, and the other end of the electrode post extends to the outside of the housing and is connected to a power supply.

[0012] The outer periphery of the electrode post is covered with an insulating sleeve.

[0013] A method for measuring the degree of space charge compensation, applied to any of the aforementioned accelerator beam space charge compensation measurement devices, includes the following steps:

[0014] S1: Obtain the initial beam parameters at the inlet end of the detachable electrode, the terminal beam parameters at the outlet end, and the electromagnetic field distribution parameters of the detachable electrode.

[0015] S2: Using the initial beam parameters and electromagnetic field distribution parameters as input conditions, and the degree of space charge compensation as a variable, the input is entered into the beam dynamics analysis software to calculate and obtain the measured beam parameters;

[0016] S3: Compare the measured beam parameters with the terminal beam parameters and calculate the error;

[0017] S4: If the error falls within the threshold range, then the current space charge compensation degree is the measured space charge compensation degree.

[0018] If the error does not fall within the threshold range, adjust the charge compensation level value and execute steps S2 to S4 until the error falls within the threshold range.

[0019] The initial beam parameters include initial beam intensity and initial beam emissivity; the terminal beam parameters include terminal beam intensity and terminal beam emissivity; the calculated beam parameters include calculated beam intensity and calculated beam emissivity.

[0020] The beam dynamics software includes, but is not limited to, TRACK, TraceWin, and SNOP.

[0021] In step S2, the beam parameters are calculated using the PIC algorithm.

[0022] The present invention has the following advantages:

[0023] (1) This invention provides an accelerator beam space charge compensation measurement device, which can measure the influence of vacuum degree and different beam intensities on the degree of space charge compensation. This invention provides a measurement device that measures the beam emittance at both ends of a detachable electrode, combined with the space charge compensation measurement method provided by this invention, to achieve the measurement of the degree of space charge compensation; the entire measurement device has a simple structure and the measurement results are accurate.

[0024] (2) The accelerator beam space charge compensation measurement device provided by the present invention can be disassembled individually, including the ion source and the equipment of each vacuum chamber, and then used as components for assembling a cyclotron accelerator, and can be used as part of the axial injection line of the cyclotron accelerator; other parts can also retain and optimize some components as part of the high-energy transmission line. Each component of the accelerator beam space charge compensation measurement device can be used for other purposes, saving costs.

[0025] (3) The accelerator beam space charge compensation measurement device provided by the present invention uses a detachable electrode to connect to the power supply group. When the electrode components that make up the power supply group are connected to the same static voltage, the accelerator beam space charge compensation measurement device can be used to analyze the influence of the bias voltage on the degree of space charge compensation, that is, to measure the degree of space charge compensation under the current voltage. When the electrode components are connected to different static voltages or radio frequency voltages, the space charge compensation device can form electrostatic lenses, beam concentrates and other electrical components, thereby measuring the degree of space charge compensation of different electrical components and providing experimental support for the design of electrostatic lenses and beam concentrates.

[0026] (4) This invention also provides a method for measuring the degree of space charge compensation in an accelerator beam space charge compensation measurement device. This method proposes to obtain the degree of space charge compensation by measuring the beam parameters at both ends of a detachable electrode and combining them with the PIC algorithm. This calculation method, combined with software calculation, reduces a large amount of manual calculation, and at the same time, the accuracy of the calculation results is higher. Attached Figure Description

[0027] Figure 1 A schematic diagram of the accelerator beam space charge compensation measurement device;

[0028] Figure 2 This is a schematic diagram of the detachable electrode structure;

[0029] In the figure: 1. Detachable electrode, 10. Electrode assembly, 11. Housing, 12. Cylindrical electrode, 13. Electrode post, 14. Insulating sleeve, 2. First diagnostic mechanism, 21. First vacuum chamber, 22. First emittance scanner, 23. First Faraday cylinder, 3. Second diagnostic mechanism, 31. Second vacuum chamber, 32. Second emittance scanner, 33. Second Faraday cylinder, 4. Solenoid magnet, 5. Ion source, 6. First DC current transformer, 7. Second DC current transformer. Detailed Implementation

[0030] The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments.

[0031] Therefore, the following detailed description of embodiments of the present invention is not intended to limit the scope of the claimed invention, but merely illustrates some embodiments of the invention. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without inventive effort are within the scope of protection of the present invention.

[0032] It should be noted that, unless otherwise specified, the embodiments and features and technical solutions in the present invention can be combined with each other.

[0033] It should be noted that similar labels and letters in the following figures indicate similar items. Therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures.

[0034] In the description of this invention, it should be noted that the terms "upper," "lower," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, or the orientation or positional relationship commonly used when the product of this invention is in use, or the orientation or positional relationship commonly understood by those skilled in the art. These terms are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this invention. In addition, the terms "first," "second," etc., are only used to distinguish descriptions and should not be construed as indicating or implying relative importance.

[0035] See Figure 1 and Figure 2 An accelerator beam space charge compensation measurement device includes a detachable electrode 1. One end of the detachable electrode 1 is fixedly connected to a first diagnostic mechanism 2, and the other end is fixedly connected to a second diagnostic mechanism 3. One end of the first diagnostic mechanism 2 is fixedly connected to one end of a solenoid magnet 4, and the other end of the solenoid magnet 4 is fixedly connected to an ion source 5. The first diagnostic mechanism 2 is used to measure the beam emittance and beam intensity at the inlet end of the detachable electrode 1, and the second diagnostic mechanism 3 is used to measure the beam emittance and beam intensity at the outlet end of the detachable electrode 1. The ion source 5, the solenoid magnet 4, the first diagnostic mechanism 2, the detachable electrode 1, and the second diagnostic mechanism 3 are coaxially arranged, so that the beam emitted from the ion source 5 is focused by the solenoid magnet, enters the first diagnostic mechanism 2, passes through the detachable electrode 1, and exits and is absorbed by the second diagnostic mechanism 3.

[0036] The beam parameters emitted from the ion source 5 and entering the detachable electrode 1 are detected by the first diagnostic device 2, and the beam parameters at the exit end of the detachable electrode 1 are detected by the second diagnostic device. By using the beam parameters at the inlet and outlet sections of the detachable electrode 1, the specific value of the space charge compensation degree is calculated.

[0037] The first diagnostic device 2 includes a first vacuum chamber 21, a first emissivity scanner 22, and a first Faraday cylinder 23. One end of the first vacuum chamber 21 is fixedly connected to the inlet end of the detachable electrode 1, and the other end is fixedly connected to the solenoid magnet 4. The first emissivity scanner 22 and the first Faraday cylinder 23 are both mounted on the first vacuum chamber 21, and are arranged parallel to each other. Furthermore, when the first emissivity scanner 22 and the first Faraday cylinder 23 are in operation, the center of their detection ends can move to the central axis of the beam transmission line.

[0038] The second diagnostic device 3 includes a second vacuum chamber 31, a second emissivity scanner 32, and a second Faraday cylinder 33. One end of the second vacuum chamber 31 is fixedly connected to the outlet end of the detachable electrode 1, and the other end is fixedly connected to the second Faraday cylinder 33. The second emissivity scanner 32 is mounted on the second vacuum chamber 31, and the second emissivity scanner 32 and the second Faraday cylinder 33 are arranged perpendicularly to each other. A vacuum pump is connected to either the first vacuum chamber 21 or the second vacuum chamber 31, and the vacuum pump provides a vacuum environment for both the first vacuum chamber 21 and the second vacuum chamber 31. Because the first vacuum chamber 21, the second vacuum chamber 31, and the detachable electrode are interconnected, they can share the same vacuum pump.

[0039] The first emissivity scanner 22 and the second emissivity scanner 32 are used to detect the beam emissivity at the inlet and outlet ends of the detachable electrode 1, respectively. The first Faraday cylinder 23 and the second Faraday cylinder 33 are used to detect the beam intensity at the inlet and outlet ends of the detachable electrode 1. The second Faraday cylinder 33 and the second emissivity scanner 32 are arranged perpendicularly to each other, that is, the second Faraday cylinder 33 is coaxially arranged with the particle beam, so that the second Faraday cylinder 33 can both measure the beam intensity and absorb the particle beam. The detection ends of the first emissivity scanner 22, the first Faraday cylinder 23, the second emissivity scanner 32, and the second Faraday cylinder 33 can all be adjusted in height. The position of the second Faraday cylinder 33 is fixed, and its center is located on the central axis of the beam transmission line, which can play the role of beam measurement and collection.

[0040] An accelerator beam space charge compensation measurement device further includes a first DC current transformer 6 and a second DC current transformer 7. One end of the first DC current transformer 6 is fixedly connected to the outlet end of the first vacuum chamber 21, and the other end is fixedly connected to the inlet end of the detachable electrode 1. One end of the second DC current transformer 7 is fixedly connected to the outlet end of the detachable electrolyzer, and the other end is fixedly connected to the inlet end of the second vacuum chamber 31. The first DC current transformer 6 and the second DC current transformer 7 can also measure the beam intensity, mainly used to further verify and confirm the accuracy of the beam intensity detected by the first Faraday cage 23 and the second Faraday cage 33.

[0041] The detachable electrode 1 includes several electrode assemblies 10, which are connected end-to-end in sequence. Each electrode assembly includes a housing 11, inside which a cylindrical electrode 12 is disposed. One end of the cylindrical electrode 12 is fixedly connected to an electrode post 13, and the other end of the electrode post 13 extends to the outside of the housing 11 and is connected to a power supply. The cylindrical electrode 12 is coaxially arranged with the particle beam, allowing the particle beam to pass through the inside of the cylindrical electrode 12.

[0042] The electrode post 13 is covered with an insulating sleeve 14. The insulating sleeve 14 is used to isolate the electrode post 13 from the housing 11 and prevent the housing 11 from short-circuiting and conducting electricity.

[0043] The working principle of this invention is:

[0044] The accelerator beam space charge compensation measurement device is operated. Once the operating conditions of the accelerator beam space charge compensation measurement device are met, the first Faraday cylinder 23 on the first vacuum chamber 21 is controlled to descend, so that the detection end of the first Faraday cylinder 23 descends to the beamline formed by the beam. At the same time, the first emittance scanner 22 and the second emittance scanner 32 are controlled to rise, so that the detection ends of the first emittance scanner 22 and the second emittance scanner 32 are lifted away from the beamline formed by the beam. Then, the ion source 5 is made to output a stable current intensity according to a preset value, and a static voltage or radio frequency voltage is applied to the detachable electrode 1 as needed. The initial beam intensity is measured at the inlet of the detachable electrode 1 using the first Faraday tube 23 on the first vacuum chamber 21. After the initial beam intensity is measured, the detection end of the first emittance scanner 22 is lowered to measure the initial emittance at the inlet of the detachable electrode 1. Then, the first emittance scanner 22 and the first Faraday tube 23 on the first vacuum chamber 21 are sequentially raised. The terminal beam intensity after passing through the detachable electrode 1 is measured using the second Faraday tube 33 at the rear end of the second vacuum chamber 31. The detection end of the second emittance scanner 32 is then lowered to the beamline of the beam to measure the emittance of the terminal beam after the detachable electrode 1. After the measurement is completed, the second emittance scanner 32 is raised. The measured beam parameters are read and input into the dynamic analysis software to calculate the degree of space charge compensation.

[0045] The method for calculating the degree of space charge compensation by measuring the initial beam current parameters at the inlet end and the terminal beam current parameters at the outlet end of the detachable electrode 1 is as follows:

[0046] A method for measuring the degree of space charge compensation is applied to the space charge compensation measuring device for accelerator beams. In this method, the vacuum levels of the first vacuum chamber 21 and the second vacuum chamber 31 are set according to experimental requirements and can be changed as needed. At the same time, the intensity of the particle beam is also set according to experimental requirements and can be changed as needed.

[0047] A method for measuring the degree of space charge compensation includes the following steps:

[0048] S1: Obtain the initial beam parameters at the inlet end of the detachable electrode 1, the terminal beam parameters at the outlet end, and the electromagnetic field distribution parameters of the detachable electrode 1. The electromagnetic field distribution parameters are calculated using electromagnetic software according to the design conditions. The initial beam parameters are obtained by measuring the first Faraday tube 23 and the first emissivity scanner 22; the terminal beam parameters are obtained by measuring the second Faraday tube 33 and the second emissivity scanner 32.

[0049] S2: Using the initial beam parameters and electromagnetic field distribution parameters as input conditions, and the space charge compensation degree as a variable, the data is input into the beam dynamics analysis software to calculate the measured beam parameters. The space charge compensation degree is a variable that can be adjusted by changing the vacuum levels of the first vacuum chamber 21 and the second vacuum chamber 31. By changing the vacuum levels of the first vacuum chamber 21 and the second vacuum chamber 31, the content of residual gas in the entire system can be adjusted. The space charge compensation degree can be adjusted by changing the content of inert gas. Residual gas includes the working gas required when the ion source generates plasma, as well as residual gases such as O2, H2O, and N2 from the vacuum system itself.

[0050] S3: Compare the measured beam parameters and the terminal beam parameters, and calculate the obtained error; in this embodiment, the method for calculating the error between the measured beam parameters and the terminal beam parameters is common knowledge and will not be elaborated in this invention. The terminal beam parameters are obtained by measurement between the second emissivity scanner 32 and the second Faraday tube 33.

[0051] S4: If the error falls within the threshold range, the space charge compensation degree in the current beam dynamics analysis software is the measured space charge compensation degree; in this embodiment, the threshold is ±0.5%, that is, when the calculated error is 100±0.5%, the space charge compensation degree of the current calculated beam parameters can be obtained as the measured space charge compensation degree.

[0052] If the error does not fall within the threshold range, adjust the charge compensation level value and execute steps S2 to S4 until the error falls within the threshold range.

[0053] The initial beam parameters include initial beam intensity and initial beam emissivity; the terminal beam parameters include terminal beam intensity and terminal beam emissivity; the calculated beam parameters include calculated beam intensity and calculated beam emissivity.

[0054] In this embodiment, the beam dynamics software includes, but is not limited to, software such as TRACK, TraceWin, and SNOP.

[0055] In step S2, the beam parameters are calculated using the PIC algorithm.

[0056] In this invention, the beam parameters are calculated using the PIC algorithm, which is a commonly used calculation method in dynamic software analysis in this field, and will not be explained further in this invention.

[0057] The accelerator space charge compensation degree measurement device and method provided by the present invention can detect the degree of space charge compensation under different vacuum conditions.

[0058] According to Liu Wei's theorem, when the particle beam motion is canonical, the particle density in phase space remains constant. In beam transmission, if the beam energy remains constant, the area of ​​the phase space ellipse remains constant, meaning the beam emittance remains constant. However, the application of Liu Wei's theorem requires that: 1) the space charge effect of the Coulomb force between particles within the beam be ignored; and 2) collisions between particles and remaining gas molecules or atoms in the transmission system be neglected. For high-current beams, especially at low energies, the space charge effect of particle interactions cannot be ignored and is the main reason for the increase in emittance and envelope. Therefore, by measuring the change in beam emittance, it is possible to determine whether the degree of space charge compensation meets the design requirements.

[0059] Specifically, the motion of charged particles is influenced by electromagnetic fields, which are generated by external electromagnetic fields. External electromagnetic fields include the electric fields generated by accelerator components. and the magnetic field generated by accelerator components and space charge field It is formed by superposition, that is:

[0060]

[0061]

[0062] For beam dynamics analysis, the space charge effect is calculated using the PIC (Particle-in-Cell) algorithm. To reduce computational complexity and improve efficiency, a group of real charged particles with similar velocities and positions can be assumed to move together and treated as a single macroparticle, thus reducing the number of charged particles that need to be calculated. The macroparticle has the same charge-to-mass ratio as the real charged particles, and weights are used to represent how many real particles each macroparticle represents. The macroparticle is tracked and simulated using the PIC algorithm. The particle distribution is divided using a grid, and the Poisson equation and boundary conditions are solved to obtain the electromagnetic field within the grid. This electromagnetic field is then superimposed with the external field to react with the particles.

[0063] The number of real particles each macroparticle represents is called the macroparticle weight. The macroparticle weight wt without charge compensation is calculated as follows:

[0064]

[0065] in, To account for the beam intensity during space charge compensation, The frequency of the particle beam, The amount of charge carried by a single electron. The number of macroparticles set in the simulation.

[0066] However, during particle beam transmission, the particle beam collides with residual gas molecules or atoms in the transmission channel, ionizing the residual molecules or atoms. The beam then captures oppositely charged ions in the vacuum chamber for neutralization, thus compensating for the influence of space charge to some extent. The degree of space charge compensation is defined as follows:

[0067]

[0068] in, To compensate for the beam intensity before / before compensation, This represents the equivalent beam intensity after space charge compensation. The degree of space charge compensation is related to the vacuum level and the electric field. In this embodiment, the electric field mainly depends on the electrical components, and the vacuum level can be adjusted by the gas flow rate at the injection port of the first vacuum chamber 21 and the vacuum pump connected to the first vacuum chamber 21 and the second vacuum chamber 31.

[0069] Therefore, after considering space charge compensation, the macroparticle weight wt' is calculated as follows:

[0070]

[0071] In this invention, the measured beam intensity is obtained by substituting the above parameters into the PIC calculation method for beam dynamics analysis. When the error between the measured beam intensity and the terminal beam intensity is within a threshold range, the space charge compensation degree is substituted into the calculation process. This refers to the degree of space charge compensation under the current vacuum level and other parameters.

[0072] Therefore, the measuring device and measuring method provided by this invention, combined with electromagnetic analysis software, can realize the measurement of the degree of space charge compensation.

[0073] The above description is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the scope of the technology disclosed in the present invention, based on the technical solution and inventive concept of the present invention, should be covered within the scope of protection of the present invention.

Claims

1. An accelerator beam space charge compensation measurement device, characterized in that, The device includes a detachable electrode (1), one end of which is fixedly connected to a first diagnostic mechanism (2) and the other end of which is fixedly connected to a second diagnostic mechanism (3). One end of the first diagnostic mechanism (2) is fixedly connected to one end of a solenoid magnet (4), and the other end of the solenoid magnet (4) is fixedly connected to an ion source (5). The first diagnostic mechanism (2) is used to measure the beam emissivity and beam intensity at the inlet end of the detachable electrode, and the second diagnostic mechanism (3) is used to measure the beam emissivity and beam intensity at the outlet end of the detachable electrode.

2. The accelerator beam space charge compensation measurement device as described in claim 1, characterized in that, The first diagnostic device (2) includes a first vacuum chamber (21), a first emissivity scanner (22) and a first Faraday tube (23). One end of the first vacuum chamber (21) is fixedly connected to the inlet end of the detachable electrode (1), and the other end is fixedly connected to the solenoid magnet (4). The first emissivity scanner (22) and the first Faraday tube (23) are both installed on the first vacuum chamber (21), and the detection end center of the first emissivity scanner (22) and the detection end center of the first Faraday tube (23) can both move to the central axis of the beam transmission line.

3. The accelerator beam space charge compensation measurement device as described in claim 2, characterized in that, The second diagnostic device (3) includes a second vacuum chamber (31), a second emissivity scanner (32), and a second Faraday cylinder (33). One end of the second vacuum chamber (31) is fixedly connected to the outlet end of the detachable electrode (1), and the other end is fixedly connected to the second Faraday cylinder (33). The second emissivity scanner (32) is mounted on the second vacuum chamber (31), and the second emissivity scanner (32) and the second Faraday cylinder (33) are arranged perpendicular to each other.

4. The accelerator beam space charge compensation measurement device as described in claim 3, characterized in that, It also includes a first DC current transformer (6) and a second DC current transformer (7). One end of the first DC current transformer (6) is fixedly connected to the outlet end of the first vacuum chamber (21), and the other end is fixedly connected to the inlet end of the detachable electrode (1). One end of the second DC current transformer (7) is fixedly connected to the outlet end of the detachable electrode, and the other end is fixedly connected to the inlet end of the second vacuum chamber (31).

5. The accelerator beam space charge compensation measurement device as described in claim 1, characterized in that, The detachable electrode (1) includes several electrode assemblies (10), which are connected end to end in sequence; each electrode assembly includes a housing (11), and a cylindrical electrode (12) is provided inside the housing (11). The cylindrical electrode (12) is fixedly connected to one end of an electrode post (13), and the other end of the electrode post (13) extends to the outside of the housing (11) and is connected to a power supply.

6. The accelerator beam space charge compensation measurement device as described in claim 5, characterized in that, The outer periphery of the electrode post (13) is covered with an insulating sleeve (14).

7. A method for measuring the degree of space charge compensation, applied to the accelerator beam space charge compensation measurement device according to any one of claims 1-6, characterized in that, Includes the following steps: S1: Obtain the initial beam parameters at the inlet end of the detachable electrode (1), the terminal beam parameters at the outlet end, and the electromagnetic field distribution parameters of the detachable electrode (1). S2: Using the initial beam parameters and electromagnetic field distribution parameters as input conditions, and the degree of space charge compensation as a variable, the input is entered into the beam dynamics analysis software to calculate and obtain the measured beam parameters; S3: Compare the measured beam parameters with the terminal beam parameters and calculate the error; S4: If the error falls within the threshold range, then the current space charge compensation degree is the measured space charge compensation degree. If the error does not fall within the threshold range, adjust the charge compensation level value and execute steps S2 to S4 until the error falls within the threshold range.

8. The method for measuring the degree of space charge compensation as described in claim 7, characterized in that, The initial beam parameters include initial beam intensity and initial beam emissivity; the terminal beam parameters include terminal beam intensity and terminal beam emissivity; the calculated beam parameters include calculated beam intensity and calculated beam emissivity.

9. The method for measuring the degree of space charge compensation as described in claim 8, characterized in that, The beam dynamics software includes, but is not limited to, software such as TRACK, TraceWin, and SNOP.

10. The method for measuring the degree of space charge compensation as described in claim 9, characterized in that, In step S2, the beam parameters are calculated using the PIC algorithm.

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