A multi-charge-state beam extraction device for a negative hydrogen ion cyclotron

Abstract

The application discloses a multi-charge-state beam extraction device for a negative hydrogen ion cyclotron, which comprises the following steps: arranging a three-charge-state beam extraction device of protons, negative hydrogen ions and hydrogen atoms on the track of the accelerated beam to an extraction energy; or arranging a double-charge-state beam extraction device of protons and negative hydrogen ions; or arranging a double-charge-state beam extraction device of protons and hydrogen atoms; and the three-charge-state or double-charge-state beam extraction device is provided with a stripping target and / or an electrostatic deflection plate which are combined by stripping films with different thicknesses and different positions, the different position stripping films are used for online adjusting the proportion of each component beam, and the different positions refer to the front and rear positions and the radial positions of the plurality of stripping films on the track of the beam extraction. The application solves the problem that the prior art can only extract a single-charge-state beam and can only online adjust the total flow intensity of each charge-state beam but cannot adjust the flow intensity of each charge-state beam.

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field of cyclotron, and particularly relates to a multi-charge-state beam extraction device for a negative hydrogen ion cyclotron. BACKGROUND

[0002] A cyclotron is a circular accelerator in which charged particles make a cyclotron motion along a closed orbit, and the particles are repeatedly accelerated by the periodic oscillation of the electric field acting on the acceleration gap. Because the cyclotron can repeatedly use the high-frequency electric field to accelerate, it can accelerate particles to a higher energy at a lower cost, and has been widely used in many fields such as nuclear physics research, aerospace, weapons, isotope production, cancer treatment, industrial irradiation, etc. Due to the small footprint, low cost, high reliability, easy maintenance, and wide range of applications, a large number of commercial and industrial cyclotrons have appeared internationally in the last century.

[0003] Among the many applications, most applications do not have special requirements for the electrical properties of the extracted beam, but with the development of scientific research, some applications have new requirements for the electrical properties of the beam: not only do they need to provide multiple charge states at one time, but also the beam intensity of each charge state needs to be adjusted flexibly online. The provision of multiple charge states at one time not only requires the provision of a negative hydrogen ion beam and / or a hydrogen atom beam in addition to the provision of a conventional proton beam.

[0004] The difficulty of simultaneously providing multiple charge states lies in that: if the electrostatic deflection extraction method is used, only one of the proton beam or the negative hydrogen ion beam can be extracted; similarly, if the stripping film extraction method is used, the negative hydrogen ion beam cannot be extracted.

[0005] The difficulty of adjusting the amount of each charge state online lies in that: because each extraction device can only extract one charge state of the beam, the total current cannot be adjusted by dividing the total current among each charge state of the beam, and if the beam intensity of a single type is to be adjusted online, the method of adjusting the injection beam intensity is used. Assuming that the same extraction device can simultaneously extract multiple charge states of the beam, when the method of adjusting the injection beam intensity is used to adjust the beam intensity of each charge state in the multiple charge states, only the total beam intensity of each charge state can be adjusted online, and the beam intensity of each charge state cannot be adjusted separately. SUMMARY

[0006] The present application is directed to the problems existing in the prior art, and proposes a multi-charge-state beam extraction structure for a negative hydrogen ion cyclotron, aiming to solve the problem that each extraction device in the prior art can only extract one kind of charge-state beam, and when adjusting the flow intensity of each charge state in the multi-charge-state by adjusting the injection beam intensity, only the total flow intensity of each charge-state beam can be adjusted online, and the flow intensity of each charge-state beam cannot be adjusted respectively.

[0007] The present application proposes the following technical solutions to solve the technical problems:

[0008] A multi-charge-state beam extraction device for a negative hydrogen ion cyclotron, characterized in that: on the trajectory of the beam accelerated to the extraction energy, a proton, negative hydrogen ion, and hydrogen atom three-charge-state beam extraction device is arranged; or a proton beam and negative hydrogen ion double-charge-state beam extraction device is arranged; or a proton and hydrogen atom double-charge-state beam extraction device is arranged; the three-charge-state or double-charge-state beam extraction device is provided with a stripping target composed of stripping films with different thicknesses and different positions and / or an electrostatic deflection plate, the stripping films with different positions are used to adjust the proportion of each component beam online, the different thicknesses refer to that the stripping films are arranged with different thicknesses according to the requirements of multi-charge-state beam extraction; the different positions refer to that on the trajectory of beam extraction, the positions of the plurality of stripping films are different in front and back and different in radial position;

[0009] Further, the proton, negative hydrogen ion, and hydrogen atom three-charge-state beam extraction device comprises a stripping target composed of stripping film A, stripping film B, and stripping film C, and an electrostatic deflection plate; the thickness of the stripping film A is the thickness at which the flow intensity of the extracted hydrogen atom H is the highest; the thicknesses of the stripping film B and the stripping film C are thick enough to make the proportion of the extracted proton H + be more than 99.9%; the middle of the stripping film B is provided with a rectangular through hole, which is used to control the electrostatic deflection plate not to be bombarded by negative hydrogen ions when the negative hydrogen ions pass through the electrostatic deflection plate.

[0010] Further, the stripping target composed of the stripping film A, the stripping film B, and the stripping film C, the width of the stripping film A, the stripping film B, and the stripping film C is greater than 150% of the beam spot size to ensure that the beam passes through the stripping film, rather than the rear support of the stripping film, the radial positions of the inside of the stripping film A and the stripping film B are the same, and the proportion of the proton beam can be adjusted online by adjusting the radial position of the stripping film C.

[0011] Further, the proportion of the proton beam can be adjusted online by adjusting the radial position of the stripping film C, specifically: when the inside radius of the stripping film C is greater than the outside radius of the small hole of the stripping film B, the proportion of the proton beam is the lowest.

[0012] Further, the proton beam proportion can be adjusted on line by adjusting the radial position of the stripping film C. Specifically, the smaller the inner radius of the stripping film C, the higher the proportion of the proton beam, and the lower the proportion of the hydrogen atom beam and the negative hydrogen ion beam. When the inner radius of the stripping film C is smaller than the inner radius of the small hole of the stripping film B, only the proton beam is extracted.

[0013] Further, the hydrogen atom beam proportion can be adjusted on line by adjusting the radial position of the stripping film A.

[0014] Further, the hydrogen atom beam proportion can be adjusted on line by adjusting the radial position of the stripping film A. Specifically, when the inner radius of the stripping film A is smaller than the inner radius of the small hole of the stripping film B, the proportion of the hydrogen atom beam is the highest.

[0015] Further, the hydrogen atom beam proportion can be adjusted on line by adjusting the radial position of the stripping film A. Specifically, the larger the inner radius of the stripping film A, the lower the proportion of the hydrogen atom beam, and the higher the proportion of the proton beam and the negative hydrogen ion beam. When the inner radius of the stripping film A is larger than the outer radius of the small hole of the stripping film B or the inner radius of the stripping film C, the proportion of the hydrogen atom beam is reduced to 0.

[0016] Further, the radial positions of the stripping film C and the stripping film A are adjusted at the same time, so that the proportions of the three charged beams can be adjusted on line.

[0017] Further, the inner radius of the stripping film A and the stripping film C cannot be smaller than the inner radius of the stripping film B, so as to prevent the stripping film A and C from stripping the particles on the trajectory of the extraction energy zone.

[0018] Further, the proton beam and negative hydrogen ion double-charge beam extraction device is composed of a stripping target composed of the stripping film B and the stripping film C and an electrostatic deflection plate. The thickness of the stripping film B and the stripping film C is thick enough to extract the proton H + The proportion is more than 99.9%. The middle of the stripping film B is provided with a rectangular through hole, which is used to control the electrostatic deflection plate not to be bombarded by negative hydrogen ions when the negative hydrogen ions pass through the electrostatic deflection plate.

[0019] Further, the stripping target composed of the stripping film B and the stripping film C can realize on-line adjustment of the proportions of the proton and the negative hydrogen ion by adjusting the position of the stripping film C.

[0020] Further, the position of the stripping film C is adjusted to realize on-line adjustment of the proportions of the proton and the negative hydrogen ion. Specifically, when the inner radius of the stripping film C is larger than the outer radius of the small hole of the stripping film B, the proportion of the proton beam is the lowest, and the proportion of the negative hydrogen ion beam is the highest.

[0021] Further, the position of the stripping film C is adjusted to realize online adjustment of the proportion of protons and negative hydrogen ions, specifically, the smaller the inner radius of the stripping film C, the higher the proportion of the proton beam and the lower the proportion of the negative hydrogen ion beam.

[0022] Further, the position of the stripping film C is adjusted to realize online adjustment of the proportion of protons and negative hydrogen ions, specifically, when the inner radius of the stripping film C is smaller than the inner radius of the small hole of the stripping film B, only the proton beam is extracted.

[0023] Further, when the radial position of the stripping film C is adjusted, the inner radius of the stripping film C cannot be smaller than the inner radius of the stripping film B, so as to prevent the stripping film C from stripping particles that do not reach the trajectory of the extraction energy zone.

[0024] Further, the proton and hydrogen atom double-charge-state beam extraction device is composed of a stripping target composed of the stripping film A and the stripping film C; the thickness of the stripping film A is the thickness at which the hydrogen atom H flow intensity is the highest when the hydrogen atom H is extracted; and the thickness of the stripping film C is thick enough to extract the hydrogen atom H + with a proportion of more than 99.9%.

[0025] Further, the stripping target composed of the stripping film A and the stripping film C realizes online adjustment of the proportion of protons and hydrogen atoms by adjusting the radial position of the stripping film C.

[0026] Further, the radial position of the stripping film C is adjusted to realize online adjustment of the proportion of protons and hydrogen atoms, specifically, the smaller the inner radius of the stripping film C, the higher the proportion of the proton beam and the lower the proportion of the hydrogen atom beam.

[0027] Further, the radial position of the stripping film C is adjusted to realize online adjustment of the proportion of protons and hydrogen atoms, specifically, when the inner radius of the stripping film C is equal to the inner radius of the stripping film A, only the proton beam is extracted.

[0028] Further, the radial position of the stripping film C is adjusted to realize online adjustment of the proportion of protons and hydrogen atoms, specifically, when the radial position of the stripping film C is adjusted, the inner radius of the stripping film C cannot be smaller than the inner radius of the stripping film A, so as to prevent the stripping film C from stripping particles that do not reach the trajectory of the extraction energy zone.

[0029] Advantages and effects of the present application

[0030] 1. The application solves the problem that the prior art can only extract single-charge-state beam and can only adjust the total beam intensity of each charge state but cannot adjust the beam intensity of each charge state by installing a stripping target and / or an electrostatic deflection plate on the beam extraction orbit, installing a plurality of stripping films with different thicknesses, longitudinal positions and radial positions on the stripping target, and adjusting the radial position of each stripping film to adjust the proportion of each component beam in line.

[0031] 2. The application ingeniously uses the feature that the sum of the beam intensities of various charge states after stripping (i.e., the total beam intensity) is equal to the beam intensity before stripping, solving the difficult problem of adjusting the proportion of each component beam in line that has long plagued technicians in the field: because the application provides a plurality of stripping films for multiple charge states on the beam extraction orbit rather than only one type of stripping film, when one of the plurality of stripping films for multiple charge states cannot extract 100% of the injected beam intensity due to adjustment of its radial position, the remaining beam intensity will be "absorbed" by other stripping films for other charge states on the extraction orbit. The reason why it is "absorbed" and not merged into the next beam group of the current stripping film is that the remaining beam intensity has a place to go rather than no place to go. Since there is a place to go, it will not continue to rotate on the accelerator extraction orbit and will not be merged into the next beam group of the current stripping film. BRIEF DESCRIPTION OF DRAWINGS

[0032] Figure 1 A multi-charge-state beam extraction principle for a negative hydrogen ion cyclotron according to the application;

[0033] Figure 2 A curve of the change of each beam component with the thickness of the stripping film during the stripping process of the negative hydrogen ion beam according to the application;

[0034] Figure 3 A stripping film structure according to the application;

[0035] Figure 4a A proton beam proportion adjustment method according to the application;

[0036] Figure 4b A proton beam proportion adjustment method according to the application;

[0037] Figure 4c A proton beam proportion adjustment method according to the application;

[0038] Figure 5a A hydrogen atom beam proportion adjustment method according to the application;

[0039] Figure 5b A hydrogen atom beam proportion adjustment method according to the application;

[0040] Figure 5cThe third method for adjusting the proportion of the hydrogen atom beam of the application;

[0041] Figure 6 The schematic diagram for introducing the proton and negative hydrogen ion double-charge-state beam of the application;

[0042] Figure 6a The first method for adjusting the proportion of the proton beam and the negative hydrogen ion beam of the application

[0043] Figure 6b The second method for adjusting the proportion of the proton beam and the negative hydrogen ion beam of the application

[0044] Figure 6c The third method for adjusting the proportion of the proton beam and the negative hydrogen ion beam of the application

[0045] Figure 7 The schematic diagram for introducing the proton and hydrogen atom double-charge-state beam of the application;

[0046] Figure 7a The first method for adjusting the proportion of the proton beam and the hydrogen atom beam of the application

[0047] Figure 7b The second method for adjusting the proportion of the proton beam and the hydrogen atom beam of the application

[0048] Figure 7c The third method for adjusting the proportion of the proton beam and the hydrogen atom beam of the application DETAILED DESCRIPTION

[0049] Design principle of the application

[0050] 1. Design of the stripping target structure. Three stripping films are installed on the stripping target (a conventional stripping target has only one stripping film), and the three stripping films are different in thickness, longitudinal position and radial position. The different thicknesses are selected according to the beam requirements, and the flow intensity of each charge-state beam obtained after stripping is different for each thickness, and the sum of the flow intensities of various charge-state beams (i.e. the total flow intensity) after stripping is equal to the flow intensity before stripping. The different longitudinal positions are the front and rear positions of the three stripping films on the beam trajectory, and the different radial positions are the positions of the three stripping films along the accelerator radius.

[0051] 2. Principle of the change of the beam components with the thickness of the stripping film during the stripping process of the negative hydrogen ion beam. As shown in FIG. 2, the three stripping films are installed on the stripping target, and the three stripping films are different in thickness, longitudinal position and radial position. Figure 2As shown, in this embodiment, negative hydrogen ions are injected from the central region of the accelerator. During the stripping process, as the thickness of the stripping film increases, electrons are stripped from the negative hydrogen ions. Each stripping process involves the loss of one or two electrons. After losing one electron, the negative hydrogen ion becomes a hydrogen atom beam; after losing two electrons, it becomes a proton beam. The proportion of hydrogen atom beams reaches a peak as the stripping film thickness changes, then gradually decreases. This decrease is due to the decreasing total number of negative hydrogen ions, thus reducing the number of hydrogen atoms generated. However, while the number of hydrogen atoms decreases, some hydrogen atoms will lose another electron, becoming protons. The number of protons stripped from hydrogen atoms gradually increases. Simultaneously, protons have difficulty gaining electrons to re-become hydrogen atoms (H) or negative hydrogen ions (H). - Therefore, once the stripping membrane reaches a certain thickness, the beam will be completely stripped into a proton beam.

[0052] 3. Principles of Multiple Release Film Thickness Design. Based on... Figure 2 The thickness of the three release films was designed based on the principle that the proportion of each component in the beam varies with different release film thicknesses. Figure 2 As shown, the horizontal axis represents the thickness of the release film, and the vertical axis represents the beam current intensity. ① When the release film thickness is 6, the current intensity of hydrogen atoms is the highest, at 60, but at this time, the negative hydrogen ion H... - and proton H + The flux intensity is only about 20. When the peel film thickness is 6, the flux intensity of hydrogen atoms is equal to that of hydrogen ions (H). - and proton H + ① The current intensity is 3 times that of hydrogen atoms; ② As the thickness of the stripping film increases, the current intensity of hydrogen atoms and negative hydrogen ions gradually decreases. When the thickness of the stripping film reaches 40, the current intensity drops to 0, but at this time the current intensity of protons reaches the highest level of close to 99.

[0053] Utilizing the above characteristics, the thickness of the stripping film for generating hydrogen atoms is designed to be close to 6, and the thickness of the stripping film for generating protons is designed to be 40. In practical applications, the thickness of the stripping film for generating protons can be as thick as possible, so that the flux density approaches 99%. Figure 2 It can be seen that the current intensity of negative hydrogen ions is at its highest (100) when the thickness of the stripping membrane on the horizontal axis is 0. Therefore, the thickness of the negative hydrogen ion stripping membrane is designed to be 0, which means that no stripping membrane is needed. However, since the electrostatic deflection plate is not bombarded by negative hydrogen ions to avoid power loss when the negative hydrogen ions reach it, a stripping membrane specifically for negative hydrogen ions is still required. The center of this stripping membrane is a rectangular window, the size of which is calculated to control the diameter of the negative hydrogen ion clusters passing through the rectangular window. This diameter ensures that the clusters do not bombard the electrostatic deflection plate when passing through it.

[0054] Figure 2 The thickness required after the beam energy is changed is different, and the maximum value of the hydrogen atom beam current can also be different. For example, if the energy is doubled, the thickness of the hydrogen atom beam peak can change from 6 to 12, and the corresponding thickness of the proton 99 can be 80, etc. These can be calculated and are prior art. Therefore, the thickness of 6, 40, etc. in this item is not universal for all energies, and whether it needs to be supplemented

[0055] 4. Design principle of radial position of multiple stripping films. The position includes longitudinal position and radial position. The longitudinal position has no sequence and can be reversed, because the proportion of each component beam is determined by the thickness of the stripping film, not the position of the stripping film before and after. The radial position of the stripping film is used to adjust the charge proportion between each stripping film. The radial position of each stripping film must be determined according to the demand of its proportion, and the radial position cannot be reversed at will. The radial position is the distance from the inside of the stripping film to the center point of the accelerator. Since the total length of the stripping film is fixed, as the radial distance from the inside of the stripping film to the center point of the accelerator changes, the width of the stripping film also changes.

[0056] 5. Adjusting the radial position of multiple stripping films instead of adjusting the injection beam current. Adjusting the radial position of multiple stripping films can change the proportion of multiple charges to each other, but adjusting the radial position of a single stripping film cannot change the flow intensity of a single type of charge, but only by adjusting the injection beam intensity. Because the total flow intensity is constant from input to output, for the extracted single type of beam, even if the radial position of stripping film C is changed (the radial distance from the inside of stripping film C is increased, and the width is shortened), most of the beam is left without passing through stripping film C to become protons, and only a small amount of the beam becomes protons. But the remaining beam is not lost but continues to rotate in the accelerator and is combined into the next beam group. When the next beam group passes through stripping film C, its flow intensity is not only the current flow intensity injected from the injection port, but also the flow intensity of the remaining beam that did not exit last time and continued to rotate in the accelerator extraction orbit. With the increase of the number of superpositions, the remaining flow intensity that continues to rotate in the accelerator extraction orbit includes the flow intensity of the remaining beam of the previous N times, until the flow intensity of the previous N times plus the flow intensity of the current beam passing through stripping film C equals 100% of the injected flow intensity. Because the accelerator has millions of beam groups per second, the process from being able to extract only a small part of the injected flow intensity to 100% of the extracted injected flow intensity is so fast that it can be ignored. That is, for the extracted single type of beam, although the radial position of stripping film C is moved, the extracted beam flow intensity cannot be changed, and 100% of the beam is still extracted. The reason is that the injected flow intensity is not lost, and the remaining beam will also be added to the next beam group.

[0057] However, when the multi-charge-state beam is extracted, the situation changes: the remaining beam does not continue to rotate on the accelerator extraction orbit, but is distributed to other stripping films with different radial positions, and because the thicknesses of the other stripping films and the current stripping film are different, different proportion and different charge-state beams are generated. The flow intensities of these different proportion and different charge-state beams are added together to equal 100% of the total injection flow intensity. Therefore, in the case of multi-charge-state extraction, the proportion between multi-charge-state beams can be adjusted by adjusting the radial positions of the stripping films. And in the case of multi-charge-state extraction, only the method of adjusting the radial position can be used, and the method of adjusting the injection current cannot be used. Because when the method of adjusting the injection beam intensity is used to adjust the flow intensity of each charge state in the multi-charge state, the total flow intensity of each charge state beam can only be adjusted online, and the flow intensity of each charge state beam cannot be adjusted separately.

[0058] Based on the above principle, the present application designs a multi-charge-state beam extraction device for a negative hydrogen ion cyclotron.

[0059] A multi-charge-state beam extraction device for a negative hydrogen ion cyclotron is shown in Figure 1 The characteristic point is that on the trajectory of the beam accelerated to the extraction energy ③, a proton, negative hydrogen ion, and hydrogen atom three-charge-state beam extraction device is arranged; or a proton beam and negative hydrogen ion double-charge-state beam extraction device is arranged; or a proton and hydrogen atom double-charge-state beam extraction device is arranged; the three-charge-state or double-charge-state beam extraction device is provided with a stripping target ① composed of stripping films with different thicknesses and different positions and / or an electrostatic deflection plate ②, the different position stripping films are used to adjust the proportion of each component beam online, the different thicknesses refer to that according to the requirements of multi-charge-state beam extraction, the stripping films are arranged to be different thicknesses; the different positions refer to that on the trajectory of the beam extraction, the radial positions of the multiple stripping films are different from each other.

[0060] Further, as shown in Figure 1 , Figure 3 The proton, negative hydrogen ion, and hydrogen atom three-charge-state beam extraction device includes a stripping target composed of stripping film A, stripping film B, and stripping film C, and an electrostatic deflection plate ②; the thickness of the stripping film A is the thickness at which the flow intensity of the hydrogen atom H is the highest when the hydrogen atom H is extracted; the thicknesses of the stripping film B and the stripping film C are thick enough to make the proportion of the extracted proton H + be more than 99.9%; the middle of the stripping film B is provided with a rectangular through hole, which is used to control the electrostatic deflection plate not to be bombarded by negative hydrogen ions when the negative hydrogen ions pass through the electrostatic deflection plate.

[0061] Furthermore, the stripping target composed of stripping membrane A, stripping membrane B, and stripping membrane C has a width greater than 150% of the beam spot size to ensure that the beam passes through the stripping membrane rather than through the support at the rear end of the stripping membrane. The radial positions of the inner sides of stripping membrane A and stripping membrane B are the same, and the proportion of the proton beam can be adjusted online by adjusting the radial position of stripping membrane C.

[0062] Supplementary notes

[0063] Peeling membranes A, B, and C are respectively mounted on membrane frames, which are connected to the peeling target. The radial back-and-forth movement of each membrane frame is controlled by a motor or other means, and their positions are fed back, so as to realize the online adjustment of the radial position of each peeling membrane.

[0064] Furthermore, such as Figure 4a As shown, the proportion of the proton beam can be adjusted online by adjusting the radial position of the stripping membrane C. Specifically, the proportion of the proton beam is lowest when the inner radius of the stripping membrane C is greater than the outer radius of the small hole in the stripping membrane B.

[0065] Furthermore, such as Figure 4c As shown, the proportion of the proton beam can be adjusted online by adjusting the radial position of the stripping membrane C. Specifically, the smaller the inner radius of the stripping membrane C, the higher the proportion of the proton beam and the lower the proportion of the hydrogen atom beam and the negative hydrogen ion beam. When the inner radius of the stripping membrane C is smaller than the inner radius of the small hole in the stripping membrane B, only the proton beam is extracted.

[0066] Furthermore, the stripping target composed of stripping membrane A, stripping membrane B, and stripping membrane C allows for online adjustment of the proportion of hydrogen atom beams by adjusting the radial position of stripping membrane A.

[0067] Furthermore, such as Figure 5a As shown, the proportion of hydrogen atom beams can be adjusted online by adjusting the radial position of the stripping film A. Specifically, the proportion of hydrogen atom beams is highest when the inner radius of the stripping film A is smaller than the inner radius of the small hole in the stripping film B.

[0068] Furthermore, such as Figure 5c As shown, the proportion of hydrogen atom beams can be adjusted online by adjusting the radial position of the stripping membrane A. Specifically, the larger the inner radius of the stripping membrane A, the lower the proportion of hydrogen atom beams and the higher the proportions of proton beams and negative hydrogen ion beams. When the inner radius of the stripping membrane A is greater than the outer radius of the small hole in the stripping membrane B or the inner radius of the stripping membrane C, the proportion of hydrogen atom beams drops to 0.

[0069] Furthermore, by simultaneously adjusting the radial positions of the stripping membrane C and the stripping membrane A, the proportion of the three charge states in the beam can be adjusted online.

[0070] Furthermore, the inner radii of stripping membrane A and stripping membrane C cannot be less than the inner radius of stripping membrane B, in order to prevent stripping membranes A and C from stripping particles that have not reached the extraction energy region trajectory in areas where the inner radius of stripping membrane B is smaller.

[0071] Furthermore, the proton beam and negative hydrogen ion dual-charge beam extraction device consists of a stripping target composed of stripping membrane B and stripping membrane C, and an electrostatic deflection plate; the thickness of stripping membrane B and stripping membrane C is sufficiently thick to extract protons H. + The proportion is over 99.9%; the stripping membrane B has a rectangular through hole in the middle, which is used to control the electrostatic deflection plate so that it is not bombarded by negative hydrogen ions when passing through it.

[0072] Furthermore, the stripping target, composed of stripping membrane B and stripping membrane C, allows for online adjustment of the proton and negative hydrogen ion ratio by adjusting the radial position of stripping membrane C.

[0073] Furthermore, such as Figure 6a As shown, the ratio of protons to negative hydrogen ions can be adjusted online by adjusting the radial position of the stripping membrane C. Specifically, when the inner radius of the stripping membrane C is greater than the outer radius of the small hole in the stripping membrane B, the proportion of the proton beam is the lowest and the proportion of the negative hydrogen ion beam is the highest.

[0074] Furthermore, by adjusting the radial position of the stripping membrane C, the proportion of protons and negative hydrogen ions can be adjusted online. Specifically, the smaller the inner radius of the stripping membrane C, the higher the proportion of the proton beam and the lower the proportion of the negative hydrogen ion beam.

[0075] Furthermore, the online adjustment of the proton and hydrogen ion ratio is achieved by adjusting the radial position of the stripping membrane C. Specifically, when the inner radius of the stripping membrane C is smaller than the inner radius of the small hole in the stripping membrane B, only the proton beam is drawn out.

[0076] Furthermore, when adjusting the radial position of the stripping membrane C, the inner radius of the stripping membrane C cannot be less than the inner radius of the stripping membrane B, in order to prevent the stripping membrane C from stripping particles that have not reached the trajectory of the extraction energy region in areas where the inner radius of the stripping membrane B is smaller.

[0077] Furthermore, the proton and hydrogen atom dual-charge beam extraction device is composed of a stripping target formed by stripping film A and stripping film C; the thickness of stripping film A is the thickness at which the hydrogen atom H current is highest when hydrogen atom H is extracted; the thickness of stripping film C is sufficiently thick to extract proton H. + It accounts for more than 99.9%.

[0078] Furthermore, the stripping target, composed of stripping membrane A and stripping membrane C, allows for online adjustment of the proton and hydrogen atom ratio by adjusting the radial position of stripping membrane C.

[0079] Further, as shown in Figure 7a , Figure 7b , Figure 7c The online adjustment of the proportion of protons and hydrogen atoms is realized by adjusting the radial position of the stripping film C, specifically, the smaller the inner radius of the stripping film C, the higher the proportion of the proton beam, and the lower the proportion of the hydrogen atom beam.

[0080] Further, as shown in Figure 7a The online adjustment of the proportion of protons and hydrogen atoms is realized by adjusting the radial position of the stripping film C, specifically, when the inner radius of the stripping film C is equal to the inner radius of the stripping film A, only the proton beam is extracted.

[0081] Further, the online adjustment of the proportion of protons and hydrogen atoms is realized by adjusting the radial position of the stripping film C, specifically, when the radial position of the stripping film C is adjusted, the inner radius of the stripping film C cannot be smaller than the inner radius of the stripping film A, so as to prevent the stripping film C from stripping the particles on the trajectory of the extraction energy region.

[0082] It should be noted that the above specific embodiments are only an explanation of the present application, and are not a limitation of the present application, and those skilled in the art can make modifications to the above embodiments without creative contribution after reading the present specification, as long as they are within the scope of the claims of the present application.

Claims

1. A multi-charge-state beam extraction device for a negative hydrogen ion cyclotron, characterized by: On the trajectory of the beam accelerated to the extraction energy, a proton, negative hydrogen ion, hydrogen atom three-charge-state beam extraction device is arranged; or a proton beam and negative hydrogen ion double-charge-state beam extraction device is arranged; or a proton, hydrogen atom double-charge-state beam extraction device is arranged; the three-charge-state or double-charge-state beam extraction device is provided with a stripping target composed of stripping films with different thicknesses and different positions and / or an electrostatic deflection plate, the different positions are used for online adjustment of the proportion of each component beam, the different thicknesses refer to that the stripping films are arranged with different thicknesses according to the requirements of multi-charge-state beam extraction, the different positions refer to that on the trajectory of the beam extraction, the multiple stripping films are different in front and back positions and different in radial positions in the direction of the beam advancement. The proton, negative hydrogen ion, hydrogen atom three-charge-state beam extraction device comprises a stripping target composed of stripping film A, stripping film B and stripping film C and an electrostatic deflection plate; the thickness of the stripping film A is the thickness at which the hydrogen atom H flow intensity is the highest when the hydrogen atom H is extracted; the thicknesses of the stripping film B and the stripping film C are thick enough to make the proportion of the extracted proton H+ be more than 99.9%; the middle of the stripping film B is provided with a rectangular through hole, which is used for controlling that the electrostatic deflection plate is not bombarded by the negative hydrogen ion when the negative hydrogen ion passes through the electrostatic deflection plate. The stripping target composed of the stripping film A, the stripping film B and the stripping film C, the width of the stripping film A, the stripping film B and the stripping film C is greater than 150% of the beam spot size to ensure that the beam passes through the stripping film instead of passing through the rear support of the stripping film, the radial positions of the inside of the stripping film A and the stripping film B are the same, and the proportion of the proton beam can be adjusted online by adjusting the radial position of the stripping film C. The stripping target composed of the stripping film A, the stripping film B and the stripping film C, the proportion of the hydrogen atom beam can be adjusted online by adjusting the radial position of the stripping film A. The radial positions of the stripping film C and the stripping film A are adjusted at the same time to realize online adjustment of the proportions of the three-charge-state beams. The inside radius of the stripping film A and the stripping film C cannot be less than the inside radius of the stripping film B to prevent the stripping film A and C from stripping the particles on the trajectory of the extraction energy area.

2. A multi-charge-state beam extraction device for a negative hydrogen ion cyclotron according to claim 1, characterized in that: The proportion of the proton beam can be adjusted online by adjusting the radial position of the stripping film C, specifically, when the inside radius of the stripping film C is greater than the outside radius of the rectangular through hole of the stripping film B, the proportion of the proton beam is the lowest.

3. The multi-charge-state beam extraction device for a negative hydrogen ion cyclotron according to claim 1, characterized by: The proportion of the proton beam can be adjusted online by adjusting the radial position of the stripping film C, specifically, the smaller the inside radius of the stripping film C, the higher the proportion of the proton beam, and the lower the proportions of the hydrogen atom beam and the negative hydrogen ion beam, when the inside radius of the stripping film C is less than the inside radius of the rectangular through hole of the stripping film B, only the proton beam is extracted.

4. The multi-charge-state beam extraction device for a negative hydrogen ion cyclotron according to claim 1, characterized by: The radial position of the stripping film A can be adjusted to online adjust the proportion of the hydrogen atom beam, specifically, when the inner radius of the stripping film A is smaller than the inner radius of the rectangular through hole of the stripping film B, the proportion of the hydrogen atom beam is the highest.

5. The multi-charge-state beam extraction device for a negative hydrogen ion cyclotron according to Claim 1, characterized by: The radial position of the stripping film A can be adjusted to online adjust the proportion of the hydrogen atom beam, specifically, when the inner radius of the stripping film A is larger, the proportion of the hydrogen atom beam is lower, and the proportion of the proton beam and the negative hydrogen ion beam is higher, when the inner radius of the stripping film A is larger than the outer radius of the rectangular through hole of the stripping film B or the inner radius of the stripping film C, the proportion of the hydrogen atom beam is reduced to 0.

6. A multi-charge state beam extraction device for a negative hydrogen ion cyclotron according to claim 1, characterized by: The stripping target composed of the stripping film B and the stripping film C and the electrostatic deflection plate; the thickness of the stripping film B and the stripping film C is thick enough to make the proportion of the extracted proton H+ above 99.9%; the middle of the stripping film B is provided with a rectangular through hole, which is used to control the electrostatic deflection plate from being bombarded by the negative hydrogen ion when the negative hydrogen ion passes through the electrostatic deflection plate.

7. A multi-charge-state beam extraction device for a negative hydrogen ion cyclotron according to claim 6, characterized in that: The stripping target composed of the stripping film B and the stripping film C realizes online adjustment of the proportion of the proton and the negative hydrogen ion by adjusting the radial position of the stripping film C.

8. A multi-charge-state beam extraction device for a negative hydrogen ion cyclotron according to claim 7, characterized in that: The radial position of the stripping film C is adjusted to realize online adjustment of the proportion of the proton and the negative hydrogen ion, specifically, when the inner radius of the stripping film C is larger than the outer radius of the rectangular through hole of the stripping film B, the proportion of the proton beam is the lowest, and the proportion of the negative hydrogen ion beam is the highest.

9. A multi-charge state beam extraction device for a negative hydrogen ion cyclotron according to claim 7, characterized in that: The radial position of the stripping film C is adjusted to realize online adjustment of the proportion of the proton and the negative hydrogen ion, specifically, when the inner radius of the stripping film C is smaller, the proportion of the proton beam is higher, and the proportion of the negative hydrogen ion beam is lower.

10. A multi-charge state beam extraction device for a negative hydrogen ion cyclotron according to claim 6, characterized by: The radial position of the stripping film C is adjusted to realize online adjustment of the proportion of the proton and the negative hydrogen ion, specifically, when the inner radius of the stripping film C is smaller than the inner radius of the rectangular through hole of the stripping film B, only the proton beam is extracted.

11. A multi-charge state beam extraction device for a negative hydrogen ion cyclotron according to claim 6, characterized in that: When the radial position of the stripping film C is adjusted, the inner radius of the stripping film C cannot be smaller than the inner radius of the stripping film B, so as to prevent the stripping film C from stripping the particles on the trajectory of the extraction energy zone when the inner radius of the stripping film C is smaller than the inner radius of the stripping film B.

12. A multi-charge-state beam extraction device for a negative hydrogen ion cyclotron according to claim 1, characterized in that: The stripping target composed of the stripping film A and the stripping film C; the thickness of the stripping film A is the thickness at which the flow intensity of the extracted hydrogen atom H is the highest; the thickness of the stripping film C is thick enough to make the proportion of the extracted proton H+ above 99.9%.

13. A multi-charge-state beam extraction device for a negative hydrogen ion cyclotron according to claim 12, characterized in that: The stripping target composed of the stripping film A and the stripping film C realizes online adjustment of the proportion of the proton and the hydrogen atom by adjusting the radial position of the stripping film C.

14. A multi-charge-state beam extraction device for a negative hydrogen ion cyclotron according to claim 13, characterized in that: The radial position of the stripping film C is adjusted to realize online adjustment of the proportion of the proton and the hydrogen atom, specifically, when the inner radius of the stripping film C is smaller, the proportion of the proton beam is higher, and the proportion of the hydrogen atom beam is lower.

15. A multi-charge-state beam extraction device for a negative hydrogen ion cyclotron according to claim 13, characterized in that: The on-line adjustment of the proportion of protons and hydrogen atoms is realized by adjusting the radial position of the stripping film C, and specifically, only a proton beam is introduced when the inner radius of the stripping film C is equal to the inner radius of the stripping film A.

16. A multi-charge-state beam extraction device for a negative hydrogen ion cyclotron according to claim 13, characterized in that: The on-line adjustment of the proportion of protons and hydrogen atoms is realized by adjusting the radial position of the stripping film C, and specifically, when the position of the stripping film C is adjusted, the inner radius of the stripping film C cannot be less than the inner radius of the stripping film A, so as to prevent the stripping film C from stripping the particles on the trajectory which have not reached the introduction energy area.

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