Electron beam focusing control device and method based on electro-dipole magnet

Abstract

An electron beam focusing control device and method based on electric dipole magnets are used for beam precise control technology of large-scale electron beam accelerators. In view of problems of high-energy electron beam transmission trajectory distortion and beam divergence under the geomagnetic field, an electron beam focusing control method based on electric dipole magnets is proposed. Firstly, according to the geomagnetic field, target coordinates and beam parameters, the beam focusing control algorithm is substituted and solved to obtain the emission angle of the electron beam with different energies. Secondly, the calculated beam emission angle is converted into the accelerator pointing and the magnetic field strength and direction of the electric dipole magnet. Finally, the excitation current amplitude of two groups of electric dipole magnets or the excitation current amplitude of one group of electric dipole magnets and the rotation angle of the rotating structure are set, so that the focusing of the electron beam is realized.

Description

TECHNICAL FIELD

[0001] The application relates to an electron beam focusing regulation device and method based on an electric dipole magnet, and belongs to the technical field of high-energy charged particle accelerators. BACKGROUND

[0002] The rapid development of high-energy electron accelerator technology promotes its wide application in the fields of industry, medical treatment and the like. From the technical characteristics, the application of the electron accelerator involves multiple professions including high-energy physics, beam optics, pulse power and the like, and has a high technical threshold. In recent years, with the continuous increase of the accelerator scale, the beam transmission distance is also getting longer, and in this case, the influence of the geomagnetic field on the beam hitting experiment effect is increasingly prominent. On the one hand, the electron beam advances in the form of Larmor circulation precession, and the radial deflection directly affects the beam hitting accuracy; on the other hand, the high-energy electron beam generated by the electron accelerator must have a certain energy distribution, and the deflection radii of different energy electrons in the spatial magnetic field are different, so that the beam flies to the target to form a beam band, causing a large drop in the beam flux density, and directly affecting the experiment effect. Therefore, it is necessary to carry out research on the spatial focusing regulation technology of high-energy electron beams.

[0003] Through the research on the large-scale accelerator technology, it is found that a most common regulation method is to configure a set of magnet groups (dipole magnet + quadrupole magnet + quadrupole magnet + dipole magnet) at the rear end of the accelerator, and with the increase of the beam transmission distance, the magnet groups need to be repeatedly used to ensure the real-time regulation of the electron beam trajectory. The problem of this method is that: first, the amount of the magnet groups is large, which increases the scale and cost of the accelerator system; second, due to the large scale of the accelerator, a large space is needed. SUMMARY

[0004] The technical problem solved by the application is to overcome the shortcomings of the prior art, and provide an electron beam focusing regulation device and method based on an electric dipole magnet, which solves the problems of electron beam transmission path distortion and beam emission, and improves the hitting accuracy and the beam flux density to the target.

[0005] The technical solution of the application is an electron beam focusing regulation device based on an electric dipole magnet, comprising a data acquisition and processing unit and a magnetic field generating device.

[0006] The data acquisition and processing unit acquires three-dimensional geomagnetic field strength, magnetic field direction angle, distance from the target point, target coordinates and different electron speeds; and according to the related preset parameters, the initial emission angle of different energy electrons is calculated; according to the initial emission angle required by different energy electrons, the magnetic field strength of the two groups of electric dipole magnets or the rotation angle of the rotation mechanism is calculated, and based on this, the output current value of the excitation current source is calculated.

[0007] The magnetic field generating device is used to generate a one-dimensional magnetic field, so that the electron beam is incident perpendicularly to the magnetic field, and the emission angle reaches the calculated setting value after the electrons pass through the effective magnetic field area length of the magnet, so as to ensure that the different energy electrons reach the same target after flying.

[0008] Further, the magnetic field generating device adopts two groups of orthogonal electric dipole magnets and their excitation current sources, or adopts a group of electric dipole magnets and their excitation current sources and a group of rotating mechanisms.

[0009] Further, the excitation current source is used to supply power to one or two groups of electric dipole magnets to control the magnetic field strength inside the magnet.

[0010] Further, the rotating mechanism carries a group of electric dipole magnets to control the direction of the magnetic field of the magnet.

[0011] Further, the emission angle of the electron beam is set to Where B is the magnetic field strength; χ is the magnetic field angle; L is the length from the target point; e is the electronic charge; m0 is the electronic rest mass; φ i is the angle between the electron emission velocity vector and the X axis; θ i is the angle between the electron emission velocity vector and the Z axis, i = 1 ~ N, N is the number of turns of the coil, γ i is the beam parameter, v i is the target coordinate, φ i is the emission angle of the electron.

[0012] Further, the magnetic induction intensity B m of the electric dipole magnet is adjusted by the output current amplitude of the excitation current source, and the relationship between them is as follows:

[0013] B m = k μ r N I

[0014] Where B m is the magnetic induction intensity of the electric dipole magnet; k is the linear correction factor; μ r is the magnetic permeability of the magnetic core; N is the number of turns of the coil; I is the excitation current amplitude.

[0015] The electron beam focusing regulation method realized by the electron beam focusing regulation device based on electric dipole magnets comprises the following steps:

[0016] S1, according to the three-dimensional magnetic induction intensity B of the geomagnetic field and the direction angle χ, the length L from the target point, the target coordinate and the beam parameter v i and γ i , the emission angle φ i and θ i of the electron beam of different energy are calculated;

[0017] S2, according to the emission angle φ of different energy electrons i and θ i , the magnetic induction intensity B of the electric dipole magnet is calculated m ; according to the emission angle φ in the XYZ rectangular coordinate system i and θ i , the two sets of electric dipole magnet pairs are set to be consistent with the calculated emission angle α i .

[0018] Further, the method for calculating the magnetic induction intensity of the electric dipole magnet is: In the formula, α i and β i are the deflection angles of the electron and the X-axis and the Z-axis respectively; d is the effective magnetic field length of the electric dipole magnet; e is the electron charge; and m0 is the electron rest mass.

[0019] A computer readable storage medium stores a computer program, and the computer program is executed by a processor to realize the steps of the electron beam focusing control method based on the electric dipole magnet.

[0020] An electron beam focusing control device based on an electric dipole magnet includes a memory, a processor, and a computer program stored in the memory and executable on the processor, and the processor executes the computer program to realize the steps of the electron beam focusing control method based on the electric dipole magnet.

[0021] Compared with the prior art, the present application has the following advantages:

[0022] (1) The present application considers the site cost, device size and economy, and only through two sets of electric dipole magnet groups or one set of electric dipole magnet and rotating mechanism, the electron beam spatial focusing in the space magnetic field environment can be realized, and the volume, weight and cost of the beam control device are greatly reduced.

[0023] (2) The present application designs an overall electron beam spatial focusing scheme, different emission angles are set for different energy electrons, so that all electrons are transmitted to the same position on the target plane under the action of the magnetic field, thereby realizing the convergence of the beam.

[0024] (3) The method uses two sets of orthogonal electric dipole magnet groups, or one set of electric dipole magnet and rotating mechanism, and uses the excitation current source to accurately control the magnetic induction intensity inside the magnet, so as to adjust the electron beam emission angle.

[0025] (4) The method has the characteristics of small size, light weight, and strong real-time performance.

[0026] (5) The proposed electron beam focusing control method based on electric diode magnets is highly practical and can be fully applied in various large-scale electron accelerator devices. This method can effectively improve beam target accuracy and beam flux density, thereby enhancing the experimental results of electron beam irradiation. Attached Figure Description

[0027] Figure 1 A flowchart for spatial focusing of an electron beam.

[0028] Figure 2 This is a schematic diagram illustrating the principle of the electron beam spatial focusing method.

[0029] Figure 3 A schematic diagram illustrating the principle of setting the electron beam emission angle for an electric diode magnet;

[0030] Figure 4 This is a block diagram of the structure of an electron beam focusing and control device based on an electric diode magnet. Detailed Implementation

[0031] To better understand the above technical solutions, the technical solutions of this application will be described in detail below with reference to the accompanying drawings and specific embodiments. It should be understood that the embodiments of this application and the specific features in the embodiments are detailed descriptions of the technical solutions of this application, rather than limitations on the technical solutions of this application. In the absence of conflict, the embodiments of this application and the technical features in the embodiments can be combined with each other.

[0032] The following description, in conjunction with the accompanying drawings, provides a more detailed account of an electron beam focusing and control device and method based on an electric diode magnet, as provided in the embodiments of this application. Specific implementation methods may include (e.g.) Figures 1-4 (As shown): Based on geomagnetic field parameters, target coordinates, and beam parameters, the emission angles of electrons with different energies are calculated. Furthermore, the magnetic field strength of the electric diodes and the rotation angle of the rotating mechanism are calculated. The magnetic field strength is controlled by the excitation current, thereby setting the initial emission angles of electrons with different energies. Specifically, it includes a data acquisition and processing unit and a magnetic field generating device. The data acquisition and processing unit acquires three-dimensional geomagnetic field strength, magnetic field direction angle, distance from the target point, target coordinates, and the velocities of different electrons. Based on relevant preset parameters, it calculates the initial emission angles of electrons with different energies. Based on the initial emission angles required for different energies, it calculates the magnetic field strength of the two sets of electric diodes or the rotation angle of the rotating mechanism. Based on this, it calculates the output current value of the excitation current source. The magnetic field generating device generates a one-dimensional magnetic field, causing the electron beam to be incident perpendicularly to the magnetic field aperture. After passing through the effective magnetic field region of the magnet, the emission angle reaches the calculated set value, ensuring that electrons with different energies reach the same target after flight.

[0033] Furthermore, in one possible implementation, the magnetic field generating device employs two sets of orthogonal electric diodes and their excitation current sources, or employs one set of electric diodes and their excitation current sources and a set of rotating mechanisms.

[0034] In one possible implementation, the excitation current source is used to power one or two sets of electric diodes, controlling the magnetic field strength inside the magnets.

[0035] Furthermore, in one possible implementation, the rotating mechanism carries a set of electric diodes to control the direction of the magnetic field.

[0036] In one possible implementation, the emission angle of the electron beam is set to... Where B is the magnetic field strength; χ is the magnetic field angle; L is the distance from the target point; e is the electron charge; m0 is the electron rest mass; φ i θ is the angle between the electron emission velocity vector and the X-axis. i γ is the angle between the electron emission velocity vector and the Z-axis, i = 1 to N, where N is the number of coil turns. i For beam parameters, v i For target coordinates, φ i The emission angle of the electron.

[0037] Furthermore, the magnetic induction intensity B of the electric diode magnet m The amplitude of the output current from the excitation current source is adjusted, and the relationship between the two is as follows:

[0038] B m =kμ r NI

[0039] In the formula, B m ρ is the magnetic flux density of the electric diode; k is the linear correction factor; μ r denoted as ρ, where ρ is the permeability of the magnetic core; N is the number of turns in the coil; and I is the amplitude of the excitation current.

[0040] Based on the same inventive concept, the present invention also provides an electron beam focusing control method implemented according to the aforementioned electron beam focusing control device based on an electric diode magnet, comprising:

[0041] S1. Based on the three-dimensional magnetic induction intensity B of the geomagnetic field, the directional angle χ, the distance from the target point L, the target coordinates, and the beam parameter v i and γ i The emission angle φ of electron beams with different energies was calculated. i and θ i ;

[0042] S2. Based on the emission angle φ of electrons with different energies i and θ i, the magnetic induction intensity B of the electromagnet is calculated m ; according to the emission angle φ i and θ i in the XYZ rectangular coordinate system, the two sets of electromagnets are set to offset the electron beam by an angle α i consistent with the calculated emission angle.

[0043] Further, the method for calculating the magnetic induction intensity of the electromagnet is as follows: wherein, α i and β i are the offset angles of the electron with respect to the X axis and the Z axis respectively; d is the effective magnetic field length of the electromagnet; e is the electronic charge; and m0 is the electronic rest mass.

[0044] In the scheme provided in the embodiments of the present application, the electron beam focusing principle based on the electromagnet is as shown in Figure 2 . The Larmor precession trajectory of the electrons with different energies in the magnetic field is used to inversely calculate the spatial transmission trajectory and the theoretical value of the emission angle of the electron beam. Based on this, the magnetic field intensity of the two sets of electromagnets or the magnetic field intensity of one set of electromagnets and the rotation angle value of the rotating mechanism are controlled, so that the emission angle of the electron beam can be accurately adjusted to be equal to the calculated theoretical value, and finally the electron beams with different energies are focused on a specific position in space.

[0045] The specific steps of the present application are as follows:

[0046] (1) According to the three-dimensional geomagnetic field intensity B, the magnetic field direction angle χ, the length L from the target point, the target coordinates and the parameters such as different electron speeds v i and the relativistic factor γ i , the initial emission angles φ i and θ i of the electrons with different energies are calculated (φ is the included angle between the electron emission speed vector and the X axis, and θ is the included angle between the electron emission speed vector and the Z axis), as shown in Figure 1 .

[0047]

[0048]

[0049] wherein, B is the magnetic field intensity; χ is the magnetic field included angle; L is the length from the target point, i.e. the length of ST in Figure 2 ; e is the electronic charge; m0 is the electronic rest mass; φ i is the included angle between the electron emission speed vector and the X axis; and θ i is the included angle between the electron emission speed vector and the Z axis.

[0050] (2) As shown in Figure 3As shown, an electric diode magnet can achieve precise adjustment of the electron beam emission direction, with the electron beam incident direction perpendicular to the magnetic field direction. The length d of the magnetic field region and the magnetic induction intensity B are also shown. m With electron velocity v i The deflection angles α of the electron beam relative to the X and Z axes i and β i The following relationship exists between them:

[0051]

[0052] (3) Figure 4 As shown, in the electron beam focusing and control device based on an electric diode magnet, the data acquisition and processing unit reads parameters such as magnetic field and beam current, calculates the electron emission angle, and sends the output current amplitude to the excitation current source of the electric diode magnet, or sends the rotation angle information to the rotating mechanism. This enables precise adjustment of the electron beam emission angle.

[0053] B m =kμ r NI

[0054] (4) The basic process of the electron beam focusing control method based on electric diode magnets is as follows: Figure 1 As shown.

[0055] This application provides a computer-readable storage medium storing computer instructions that, when executed on a computer, cause the computer to perform... Figure 1 The method described.

[0056] Those skilled in the art will understand that embodiments of this application can be provided as methods, systems, or computer program products. Therefore, this application can take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, this application can take the form of a computer program product implemented on one or more computer-usable storage media (including, but not limited to, disk storage and optical storage) containing computer-usable program code.

[0057] This application is described with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of this application. It will be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, special-purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, generate instructions for implementing the flowchart... Figure 1 One or more processes and / or boxesFigure 1 means for performing the function specified in the block or blocks.

[0058] These computer program instructions can also be stored in a computer readable memory that can direct a computer or other programmable data processing apparatus to function in a Figure 1 one or more flowcharts and / or blocks Figure 1 means for performing the function specified in the block or blocks.

[0059] These computer program instructions can also be loaded onto a computer or other programmable data processing apparatus to cause a series of operational steps to be performed on the computer or other programmable apparatus to produce a computer implemented process such that the instructions which execute on the computer or other programmable apparatus provide steps for implementing the flowcharts and / or blocks Figure 1 one or more flowcharts and / or blocks ​ means for performing the function specified in the block or blocks.

[0060] It is to be understood that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting; it is also possible in the

[0061] Obviously, numerous modifications and variations of the present application are possible in light of the above teachings. It is therefore to be understood that within the scope of the

[0062] Those skilled in the art will appreciate that the application described herein is susceptible to variations and modifications other than those specifically described. It is to be understood that the application includes all such variations and modifications which fall within the spirit and scope of the present application.

Claims

1. An electron beam focusing control device based on electro-diamagnetic magnets, characterized by, The magnetic field generating device comprises a data acquisition and processing unit and a magnetic field generating device. The data acquisition and processing unit acquires three-dimensional magnetic field intensity, magnetic field direction angle, distance from the target point, target coordinates, and different electron speeds; and according to relevant preset parameters, calculates the initial emission angle of different energy electrons; according to the initial emission angle required by different energy electrons, calculates the magnetic field intensity of the two groups of electric dipole magnets or the rotation angle of the rotation mechanism, and based on this, calculates the output current value of the excitation current source. The magnetic field generating device is used to generate a one-dimensional magnetic field, so that the electron beam is perpendicular to the magnetic field plane and is incident, and after the electrons pass through the effective magnetic field area length of the magnet, the emission angle reaches the calculated setting value, ensuring that different energy electrons reach the same target after flying. The magnetic field generating device adopts two groups of orthogonal electric dipole magnets and their excitation current sources, or adopts one group of electric dipole magnets and their excitation current sources and one group of rotation mechanisms. The emission angle of the electron beam is set to where B is the magnetic field strength; χ is the magnetic field angle; L is the length from the target point; e is the electron charge; m0 is the electron rest mass; φ i is the angle between the electron emission velocity vector and the X-axis; θ i is the angle between the electron emission velocity vector and the Z-axis, i = 1 ~ N, N is the number of turns of the coil, γ i is the beam parameter, v i is the target coordinate.

2. The electron beam focusing control device based on electro-diamagnetic magnet according to claim 1, characterized in that, The excitation current source is used to supply power to one or two groups of electric dipole magnets to control the magnetic field intensity inside the magnet.

3. The electron beam focusing and steering device based on electro-diamagnetic magnets according to claim 1, characterized in that, The rotation mechanism carries a group of electric dipole magnets to control the direction of the magnet magnetic field.

4. The electron beam focusing control device based on electro-diamagnetic iron according to claim 1, characterized in that, The magnetic induction B of the electrically diamagnetic magnet m The output current amplitude of the excitation current source is adjusted, and the relationship between them is as follows: B m = kμ r NI where B m is the magnetic induction of the electrically biased magnet; k is a linear correction factor; μ r is the magnetic permeability of the core; N is the number of turns of the coil; and I is the amplitude of the excitation current.

5. The electron beam focusing control method based on the electron beam focusing control device of claim 1, wherein, The computer program is executed by the processor to realize the steps of the method of any one of claims 5-6. S1, according to the magnetic field intensity B and magnetic field angle χ, the length L from the target point, the target coordinate v i and beam parameters γ i , the emission angle φ i and θ i of the electron beam of different energy are calculated S2, the emission angle φ of the different energy electron beam i and θ i , the magnetic induction intensity B of the electric dipole magnet is calculated m ; according to the emission angle φ i and θ i in the XYZ rectangular coordinate system, the two sets of electric dipole magnets are set to be consistent with the calculated emission angle α i .

6. The method of claim 5, wherein, The method for calculating the magnetic induction intensity of the electromagnet is: In the formula, α i and β i are the offset angles of the electron and the X-axis and the Z-axis respectively; d is the effective magnetic field length of the electromagnet; e is the electronic charge; and m0 is the electronic rest mass.

7. A computer-readable storage medium storing a computer program, the computer program comprising instructions that, when executed by a computer, cause the computer to perform the method of any one of claims 1 to 6. The processor executes the computer program to realize the steps of the method of any one of claims 5-6.

8. An electron beam focusing control device based on electro-dipole magnets, comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, characterized in that: ​

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