Device and method for controlling angular distribution uniformity of isotropic thermal neutron radiation field

Abstract

The invention relates to an isotropic thermal neutron radiation field angle distribution uniformity control device and method, and the device is characterized in that a particle accelerator is used for emitting a high-energy charged particle beam with a beam position; the beryllium target is placed along the emission line of the high-energy charged particle beam, and the high-energy charged particle beam bombards the beryllium target to generate charges; the insulation isolation gasket is wound on the outer side of the beryllium target and prevents the charges from being led out from the outside through the beryllium target; and the adjusting assembly is connected with the beryllium target and used for acquiring the electric charge quantity on the beryllium target, and is connected with the particle accelerator and used for adjusting the angle of the high-energy charged particle beam irradiating to the beryllium target. According to the invention, the purposes of preventing the charges from being exported outwards based on the insulation isolation gasket and obtaining the charge quantity by the adjusting assembly to adjust the particle accelerator are achieved, so that after the insulation isolation gasket with low cost is used for isolation, the charge quantity is detected to adjust the particle accelerator, and the technical effect of effectively saving the cost is achieved.

Description

Technical Field

[0001] The present invention relates to the technical field of thermal neutron radiation fields, and in particular to a device and method for controlling the angular distribution uniformity of an isotropic thermal neutron radiation field. Background Art

[0002] Thermal neutron activation analysis, as a nondestructive, highly sensitive analytical and detection technology, plays an important role in fields such as materials science, medicine, archaeology, and forensic medicine. Uniform thermal neutron irradiation is crucial for improving measurement accuracy and repeatability, ensuring reliable results. The thermal neutron generation method, based on a large moderator and dual targets, produces an isotropic thermal neutron radiation field. Three neutron fluence detectors monitor the neutron fluence at three different locations, providing feedback to adjust the particle beam position.

[0003] However, in related technologies, neutron fluence detectors mostly use gamma-supplemented ionization chambers to accurately measure the neutron fluence under high gamma background. The cost of neutron fluence detectors is relatively high, and in order to ensure that the feedback adjustment of the particle beam position is more accurate, at least three detectors are required to feedback the neutron situation during the entire thermal neutron irradiation, and the overall device cost is relatively high.

[0004] The above problems need to be solved urgently. Summary of the Invention

[0005] The invention discloses a device and method for controlling the uniformity of angular distribution of an isotropic thermal neutron radiation field, aiming to solve the technical problems existing in the prior art.

[0006] The present invention adopts the following technical solutions:

[0007] On the one hand, the present invention provides an isotropic thermal neutron radiation field angular distribution uniformity control device, which includes: a particle accelerator, which is used to emit a high-energy charged particle beam with a beam position; a beryllium target, which is placed along the emission line of the high-energy charged particle beam, and the high-energy charged particle beam bombards the beryllium target to generate electric charge; an insulating isolation gasket, which is wrapped around the outside of the beryllium target, and blocks the electric charge from being conducted from the beryllium target to the outside; an adjustment component, which is connected to the beryllium target and is used to obtain the amount of charge on the beryllium target, and is connected to the particle accelerator and is used to adjust the angle at which the high-energy charged particle beam is emitted toward the beryllium target.

[0008] Optionally, the beryllium target includes an upper beryllium target and a lower beryllium target, and the upper beryllium target and the lower beryllium target are both distributed along the emission line of the high-energy charged particle beam; a spacing distance is set between the upper beryllium target and the lower beryllium target, and the lower edge line of the upper beryllium target and the upper edge line of the upper beryllium target are in the same horizontal plane.

[0009] Optionally, the distance between the upper beryllium target and the lower beryllium target is set to at least 50CM.

[0010] Optionally, the upper beryllium target and the lower beryllium target are both in a semicircular pancake-shaped structure, and the orthographic projections of the upper beryllium target and the lower beryllium target form a complete circle.

[0011] Optionally, the adjustment component includes an electrostatic needle and a single-chip microcomputer controller; the electrostatic needle is connected to the beryllium target, and the electrostatic needle is used to obtain the charge on the beryllium target and convert it into a voltage signal based on the charge; the electrostatic needle is connected to the single-chip microcomputer controller, and the single-chip microcomputer controller determines the amount of charge generated on the beryllium target based on the voltage signal and adjusts the angle of the high-energy charged particle beam emitted toward the beryllium target.

[0012] Optionally, the electrostatic needle includes a first electrostatic needle and a second electrostatic needle; the first electrostatic needle is connected to the upper beryllium target to obtain a first voltage signal corresponding to the upper beryllium target; the second electrostatic needle is connected to the lower beryllium target to obtain a second voltage signal corresponding to the lower beryllium target; the single-chip microcomputer controller determines the first charge corresponding to the upper beryllium target based on the first voltage signal, and determines the second charge corresponding to the lower beryllium target based on the second voltage signal; the single-chip microcomputer controller adjusts the angle of the high-energy charged particle beam emitted toward the beryllium target based on the first charge and the second charge.

[0013] Optionally, the particle accelerator includes an accelerator body and an XY bidirectional beam controller; the accelerator body emits the high-energy charged particle beam, and the high-energy charged particle beam adjusts the beam position through the XY bidirectional beam controller; the XY bidirectional beam controller is connected to the adjustment component, and the adjustment component is used to control the XY bidirectional beam controller to adjust the beam position of the high-energy charged particle beam.

[0014] According to another aspect of an embodiment of the present invention, a method for controlling the uniformity of the angular distribution of an isotropic thermal neutron radiation field is provided, comprising: an accelerator body emits a high-energy charged particle beam; the high-energy charged particle beam is adjusted in beam position by an XY bidirectional beam controller; part of the charged particles in the high-energy charged particle beam bombards an upper beryllium target, and another part of the charged particles bombards a lower beryllium target, generating electric charges, wherein the sum of the charged particles bombarding the upper beryllium target and the charged particles bombarding the lower beryllium target is the sum of the charged particles in the high-energy charged particle beam; a first electrostatic needle obtains the charge on the upper beryllium target, and a second electrostatic needle obtains the charge on the lower beryllium target; and a single-chip microcomputer controller adjusts the beam position of the high-energy charged particle beam emitted by the XY bidirectional beam controller based on the charges corresponding to the upper beryllium target and the lower beryllium target.

[0015] Optionally, the single-chip microcomputer controller adjusts the beam position of the high-energy charged particle beam emitted by the XY bidirectional beam controller based on the charges corresponding to the upper beryllium target and the lower beryllium target, including: the first electrostatic needle obtains the charge corresponding to the upper beryllium target and converts it into a first voltage signal; the second electrostatic needle obtains the charge corresponding to the lower beryllium target and converts it into a second voltage signal; the single-chip microcomputer controller receives the first voltage signal to determine the first charge amount corresponding to the upper beryllium target, and receives the second voltage signal to determine the second charge amount corresponding to the lower beryllium target; the single-chip microcomputer controller adjusts the beam position of the high-energy charged particle beam emitted by the XY bidirectional beam controller based on the first charge amount and the second charge amount.

[0016] Optionally, the single-chip microcomputer controller adjusts the beam position of the high-energy charged particle beam emitted by the XY bidirectional beam controller based on the first charge amount and the second charge amount, including: determining the difference between the first charge amount and the second charge amount; when the difference is positive, controlling the beam position of the high-energy charged particle beam emitted by the XY bidirectional beam controller to deflect toward the direction of the lower beryllium target; when the difference is negative, controlling the beam position of the high-energy charged particle beam emitted by the XY bidirectional beam controller to deflect toward the direction of the upper beryllium target.

[0017] The technical solution adopted by the present invention can achieve at least one of the following beneficial effects:

[0018] In an embodiment of the present invention, a particle accelerator is used to emit a high-energy charged particle beam with a beam position; a beryllium target is placed along the emission line of the high-energy charged particle beam, and the high-energy charged particle beam bombards the beryllium target, generating an electric charge; an insulating isolation washer is wrapped around the beryllium target to block the charge from being discharged from the beryllium target to the outside; and an adjustment component is connected to the beryllium target to obtain the charge on the beryllium target and connected to the particle accelerator to adjust the angle at which the high-energy charged particle beam is emitted toward the beryllium target. This achieves the purpose of using the insulating isolation washer to block the charge from being discharged outward, and the adjustment component to obtain the charge to adjust the particle accelerator. This achieves the technical effect of eliminating the need for multiple, expensive detectors to detect neutrons for particle accelerator adjustment. Instead, the particle accelerator is adjusted using the cheaper insulating isolation washer after the neutrons are blocked, effectively saving costs. This solves the technical problem of the high cost of adjusting the particle accelerator, which is caused by the need for at least three expensive detectors to provide full neutron feedback in the related art. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following briefly introduces the drawings required for describing the embodiments, which constitute a part of the present invention. The exemplary embodiments of the present invention and their descriptions are provided to explain the present invention and do not constitute an undue limitation of the present invention. In the drawings:

[0020] Figure 1 1 is a schematic structural diagram of an isotropic thermal neutron radiation field angular distribution uniformity control device in Example 1 of the present invention;

[0021] Figure 2 1 is a schematic structural diagram of a beryllium target in an isotropic thermal neutron radiation field angular distribution uniformity control device in Example 1 of the present invention;

[0022] Figure 3 This is a schematic structural diagram of an insulating isolation gasket surrounding a beryllium target in an isotropic thermal neutron radiation field angular distribution uniformity control device in Example 1 of the present invention;

[0023] Figure 4 This is a schematic structural diagram of a high-energy charged particle beam passing through a beryllium target in an isotropic thermal neutron radiation field angular distribution uniformity control device in Example 1 of the present invention;

[0024] Figure 5 This is a flow chart of a method for controlling the uniformity of the angular distribution of an isotropic thermal neutron radiation field in Example 2 of the present invention;

[0025] Figure 6 This is a flow chart of an optional method for controlling the uniformity of the angular distribution of the isotropic thermal neutron radiation field in Example 4 of the present invention.

[0026] Description of reference numerals:

[0027] 1. Particle accelerator; 11. Accelerator body; 12. XY bidirectional beam controller;

[0028] 2. Beryllium target; 21. Upper beryllium target; 22. Lower beryllium target;

[0029] 3. Insulation isolation gasket;

[0030] 4. Adjustment component; 41. First electrostatic needle; 42. Second electrostatic needle; 43. Single chip microcomputer controller. DETAILED DESCRIPTION

[0031] To make the objectives, technical solutions, and advantages of the present invention more clear, the technical solutions of the present invention will be clearly and completely described below in conjunction with specific embodiments of the present invention and corresponding drawings. In the description of the present invention, it should be noted that the term "or" is generally used in the sense of including "and / or" unless the content clearly indicates otherwise.

[0032] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or a magnetic connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be a connection between the two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to the specific circumstances. In addition, in the description of this application, the terms "first", "second", etc. are only used to distinguish the description, and cannot be understood as indicating or implying relative importance. In the description of the present invention, the meaning of "plurality" is at least two, such as two, three or more, etc., unless otherwise clearly specified and limited.

[0033] Obviously, the embodiments described are only some of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0034] First, to facilitate understanding of the embodiments of the present invention, some of the terms or nouns involved in the present invention are explained below:

[0035] Isotropy refers to a physical quantity having the same properties or distribution in all directions in space. For neutron flux, isotropy means that the intensity or density of the neutron flux is uniform in all directions in space, with no specific directionality.

[0036] The thermal neutron radiation field is a radiation environment composed of low-energy neutrons. The energy range of thermal neutrons is usually 0.01 to 0.1 electron volts (eV), corresponding to a speed of about 2.2 km / s (the most probable speed of the Maxwell-Boltzmann distribution at 290K).

[0037] Beryllium targets are made with metallic beryllium (Be) as its core material. Beryllium is the fourth element in the periodic table and an alkaline earth metal with an atomic weight of 9.012. Beryllium targets are typically made from high-purity beryllium metal. They are a hard, gray metal with a hexagonal close-packed crystal structure.

[0038] To solve the problems existing in the prior art, the embodiments of the present application provide a device and method for controlling the uniformity of the angular distribution of an isotropic thermal neutron radiation field.

[0039] Example 1

[0040] This embodiment provides an isotropic thermal neutron radiation field angular distribution uniformity control device, such as Figure 1 As shown, Figure 11 is a schematic structural diagram of an isotropic thermal neutron radiation field angular distribution uniformity control device in Example 1 of the present invention, the device comprising:

[0041] A particle accelerator 1 is used to emit a high-energy charged particle beam with a beam position; a beryllium target 2 is placed along the line along which the high-energy charged particle beam is emitted. The high-energy charged particle beam bombards the beryllium target 2, generating an electric charge; an insulating isolation gasket 3 is wrapped around the outside of the beryllium target 2 to prevent the electric charge from being discharged from the beryllium target 2 to the outside; an adjustment component 4 is connected to the beryllium target 2 to obtain the amount of charge on the beryllium target 2 and is connected to the particle accelerator 1 to adjust the angle at which the high-energy charged particle beam is emitted toward the beryllium target 2.

[0042] Based on the above structure, particle accelerator 1 emits a high-energy charged particle beam and simultaneously adjusts the deflection angle of the high-energy charged particle beam. The high-energy charged particle beam can be a high-energy proton or D ion beam. Particle accelerator 1 is mounted at the end of a cylindrical beamline tube (target tube), emitting a high-energy charged particle beam from this end. The beamline tube is set to a vacuum state. The high-energy charged particle beam moves horizontally within the beamline tube, unaffected by air, and continuously moves along an extension of the emission direction until it reaches the beryllium target 2 at the other end of the beamline tube, where it reacts with the beryllium target 2. In order to ensure that the high-energy charged particle beam bombards the beryllium target 2 vertically and the high-energy charged particle beam is emitted along the central axis of the beam line pipe, it is necessary to adjust the deflection direction of the high-energy charged particle beam so that the high-energy charged particle beam is emitted along the central axis of the beam line pipe, so as to achieve the thermal neutron radiation field generated after the high-energy charged particle beam reacts with the beryllium target 2 to be isotropic, thereby achieving the effect of a uniform radiation field.

[0043] Optionally, a high-energy charged particle beam bombards the beryllium target 2, ionizing the electrons in the outer layer of the beryllium atoms, generating secondary electron-ion pairs, and releasing neutrons. The neutrons will form an isotropic thermal neutron radiation field around the beryllium target 2. Under the action of the insulating isolation gasket 3, the electrons cannot escape the range surrounded by the insulating isolation gasket 3, and the electrons carry an electric charge. To ensure that the high-energy charged particle beam is emitted along the central axis of the beam line pipe, the adjustment component 4 needs to obtain the charge in the insulating isolation gasket 3 and adjust the deflection direction of the high-energy charged particle beam according to the amount of charge corresponding to the charge. Among them, when a beam line pipe (target tube) is set between the particle accelerator 1 and the beryllium target 2, the target tube and the beryllium target 2 are fixed by a target tube fixing plate. The beryllium target has a sheet-like structure and can also be called a target plate. The insulating isolation gasket 3 is set between the target tube fixing plate and the target plate.

[0044] Alternatively, instead of expensive neutron detectors, the charge of the electrons generated during the reaction can be detected by trapping them. This simple and inexpensive method can also be used to adjust the deflection direction of the high-energy charged particle beam, effectively reducing the overall cost of the experiment.

[0045] In some preferred embodiments, the beryllium target 2 includes an upper beryllium target 21 and a lower beryllium target 22. The upper beryllium target 21 and the lower beryllium target 22 are both distributed along the line of emission of the high-energy charged particle beam. A spacing distance is set between the upper beryllium target 21 and the lower beryllium target 22. The lower edge of the upper beryllium target 21 and the upper edge of the upper beryllium target 21 are on the same horizontal plane. Figure 2 As shown, Figure 2 Schematic diagram of the structure of the beryllium target 2 in an isotropic thermal neutron radiation field angular distribution uniformity control device in Example 1 of the present invention.

[0046] Based on the above structure, in order to determine whether the high-energy charged particle beam has deviated, the beryllium target 2 is divided into an upper beryllium target 21 and a lower beryllium target 22. The upper beryllium target 21 and the lower beryllium target 22 are placed symmetrically, and the lower edge of the upper beryllium target 21 and the upper edge of the lower beryllium target 22 are on the same horizontal line. By detecting the charge on the upper beryllium target 21 and the charge on the lower beryllium target 22, when the charge on the upper beryllium target 21 is greater than the charge on the lower beryllium target 22, it indicates that the high-energy charged particle beam has deviated upward. At this time, the adjustment component 4 intervenes to adjust the beam position of the particle accelerator 1, thereby maintaining the high-energy charged particle beam on the central axis.

[0047] Optionally, due to the thickness of the insulating spacer 3, after the insulating spacer 3 surrounds the upper beryllium target 21 and the lower beryllium target 22, in order to ensure that the edges of the upper beryllium target 21 and the lower beryllium target 22 are at the same horizontal position, the positions of the two targets need to be staggered, that is, one in front and the other in the back. In this case, the edges of the upper beryllium target 21 and the lower beryllium target 22 are at the same horizontal position. As shown in the figure, the upper beryllium target 21 can be placed close to the particle accelerator 1 and the lower beryllium target 22 can be placed away from the particle accelerator 1. Alternatively, the upper beryllium target 21 can be placed away from the particle accelerator 1 and the lower beryllium target 22 can be placed close to the particle accelerator 1.

[0048] In some preferred embodiments, the distance between the upper beryllium target 21 and the lower beryllium target 22 is set to be at least 50 cm.

[0049] Based on the above structure, in order for the high-energy charged particle beam to interact with each other when reacting on the upper beryllium target 21 and the lower beryllium target 22 respectively, the distance between the upper beryllium target 21 and the lower beryllium target 22 needs to be set to be greater than 50 cm. Specifically, the high-energy charged particle beam is equivalent to a thicker cylindrical beam. After the beam is emitted, the upper part bombards the upper beryllium target 21 and is blocked by the upper beryllium target 21. The lower part of the beam of high-energy charged particles continues to shoot to the right end until it bombards the lower beryllium target 22. In order to avoid the reaction on the surface of the upper beryllium target 21 and the reaction on the surface of the lower beryllium target 22 from interacting with each other, the distance between the upper beryllium target 21 and the lower beryllium target 22 needs to be increased to at least 50 cm.

[0050] In some preferred embodiments, the upper beryllium target 21 and the lower beryllium target 22 are both in a semicircular pancake-shaped structure, and the orthographic projections of the upper beryllium target 21 and the lower beryllium target 22 form a complete circle. Figure 3 and Figure 4 As shown, Figure 3 It is a structural schematic diagram of an insulating isolation gasket 3 surrounding a beryllium target 2 in an isotropic thermal neutron radiation field angular distribution uniformity control device in Example 1 of the present invention. Figure 4 It is a structural schematic diagram of a high-energy charged particle beam passing through a beryllium target 2 in an isotropic thermal neutron radiation field angular distribution uniformity control device in Example 1 of the present invention.

[0051] Based on the above structure, the high-energy charged particle beam is cylindrical. To ensure that all particles strike beryllium target 2 when bombarding the upper and lower beryllium targets 21, 22, the shape of beryllium target 2 is designed to be identical to the cross-sectional shape of the high-energy charged particle beam. Therefore, the upper and lower beryllium targets 21, 22, when joined, form a circular structure, with the upper and lower beryllium targets 21, 22 each forming a semicircular structure. Furthermore, the upper and lower beryllium targets 21, 22 are identical in shape and size, and are symmetrically positioned along the extended line of the high-energy charged particle beam.

[0052] Optionally, the upper beryllium target 21 and the lower beryllium target 22 are both arranged in a semicircular shape. When the high-energy charged particle beam completely bombards the beryllium target 2 , the material usage of the beryllium target 2 can be reduced, thereby saving costs.

[0053] In some preferred embodiments, the adjustment component 4 includes an electrostatic needle and a single-chip microcomputer controller 43; the electrostatic needle is connected to the beryllium target 2, and the electrostatic needle is used to obtain the charge on the beryllium target 2 and convert it into a voltage signal based on the charge; the electrostatic needle is connected to the single-chip microcomputer controller 43, and the single-chip microcomputer controller 43 determines the amount of charge generated on the beryllium target 2 based on the voltage signal and adjusts the angle of the high-energy charged particle beam emitted toward the beryllium target 2.

[0054] Based on the above structure, the adjustment component 4 includes an electrostatic needle and a single-chip microcomputer controller 43. The electrostatic needle extracts the charge trapped on the beryllium target 2 by the isolation insulating gasket, amplifies the charge, and converts the charge into a voltage signal or a current signal. The electrostatic needle is connected to the single-chip microcomputer controller 43 based on a wire wrapped with insulating rubber. The voltage signal or current signal is transmitted to the single-chip microcomputer controller 43 through the wire. The single-chip microcomputer controller 43 converts the voltage signal into information on the amount of charge, thereby determining the amount of charge generated on the beryllium target 2, that is, the number of electrons generated on the beryllium target 2. The amount of neutrons can be determined based on the number of electrons, thereby realizing the function of a high-cost detector.

[0055] In some preferred embodiments, the electrostatic needle includes a first electrostatic needle 41 and a second electrostatic needle 42; the first electrostatic needle 41 is connected to the upper beryllium target 21 to obtain a first voltage signal corresponding to the upper beryllium target 21; the second electrostatic needle 42 is connected to the lower beryllium target 22 to obtain a second voltage signal corresponding to the lower beryllium target 22; the single-chip microcomputer controller 43 determines the first charge corresponding to the upper beryllium target 21 based on the first voltage signal, and determines the second charge corresponding to the lower beryllium target 22 based on the second voltage signal; the single-chip microcomputer controller 43 adjusts the angle of the high-energy charged particle beam emitted toward the beryllium target 2 based on the first charge and the second charge.

[0056] Based on the above structure, since there are an upper beryllium target 21 and a lower beryllium target 22, and it is necessary to measure the first charge of the upper beryllium target 21 and the second charge of the lower beryllium target 22, a first electrostatic needle 41 and a second electrostatic needle 42 are provided. The first electrostatic needle 41 is connected to the upper beryllium target 21 and is used to extract the charge in the upper beryllium target 21 and transmit it to the single-chip microcomputer controller 43 via a wire. The single-chip microcomputer controller 43 simultaneously collects the first charge of the upper beryllium target 21 and the second charge of the lower beryllium target 22. If the first charge is greater than the second charge, it means that the number of particles impacting the upper beryllium target 21 in the high-energy charged particle beam is greater than the number of particles impacting the lower beryllium target 22. It is necessary to adjust the deflection direction of the high-energy charged particle beam slightly downward to ensure that the emission direction of the high-energy charged particle beam coincides with the direction of the central axis.

[0057] Optionally, by converting the charge carried by the electrons into a voltage signal or a current signal, it is possible to more conveniently extract the electrons and transmit them in the wires. Only a wire line is required to transmit the charge quantity information to the microcontroller controller 43, effectively reducing material costs.

[0058] In some preferred embodiments, the particle accelerator 1 includes an accelerator body 11 and an XY bidirectional beam controller 12; the accelerator body 11 emits a high-energy charged particle beam, and the high-energy charged particle beam is adjusted in beam position by the XY bidirectional beam controller 12; the XY bidirectional beam controller 12 is connected to the adjustment component 4, and the adjustment component 4 is used to control the XY bidirectional beam controller 12 to adjust the beam position of the high-energy charged particle beam.

[0059] Based on the above structure, the particle accelerator 1 includes an accelerator body 11 and an XY bidirectional beam controller 12, wherein an electric field exists in the accelerator body 11, which accelerates the emitted charged particles so that the charged particles form high-speed emitted particles. The high-speed emitted particles enter the XY bidirectional beam controller 12 and are deflected at an angle under the action of the XY bidirectional beam controller 12, so that the emitted particles are high-speed and have a high-energy charged particle beam with a deflection direction. The high-energy charged particle beam bombards the upper target material and the lower target material. When the amount of charge generated on the two is different, the single-chip microcomputer controller 43 will adjust the deflection angle of the XY bidirectional beam controller 12 based on the charge amount, thereby adjusting the deflection angle of the high-energy charged particles, effectively realizing the formation of an isotropic thermal neutron radiation field after the high-energy charged particles bombard the target material.

[0060] Example 2

[0061] Based on the above embodiments, the present invention further proposes an implementation method for controlling the uniformity of the angular distribution of isotropic thermal neutron radiation field. Figure 5 FIG. 1 is a flow chart of a method for controlling the uniformity of the angular distribution of an isotropic thermal neutron radiation field in Example 2 of the present invention. Figure 5 As shown, the method includes:

[0062] Step S102: the accelerator body 11 emits a high-energy charged particle beam;

[0063] Step S104, the high-energy charged particle beam is adjusted in position by the XY bidirectional beam controller 12;

[0064] Step S106: Some of the charged particles in the high-energy charged particle beam bombard the upper beryllium target 21, and another part of the charged particles bombard the lower beryllium target 22, generating electric charges. The sum of the charged particles bombarding the upper beryllium target 21 and the charged particles bombarding the lower beryllium target 22 is the total amount of charged particles in the high-energy charged particle beam.

[0065] Step S108 , the first electrostatic needle 41 acquires the charge on the upper beryllium target 21 , and the second electrostatic needle 42 acquires the charge on the lower beryllium target 22 ;

[0066] In step S110 , the single chip controller 43 adjusts the beam position of the high energy charged particle beam emitted by the XY bidirectional beam controller 12 based on the charges corresponding to the upper beryllium target 21 and the lower beryllium target 22 .

[0067] In some preferred embodiments, the single-chip microcomputer controller 43 adjusts the beam position of the high-energy charged particle beam emitted by the XY bidirectional beam controller 12 based on the charges corresponding to the upper beryllium target 21 and the lower beryllium target 22, including: the first electrostatic needle 41 obtains the charge corresponding to the upper beryllium target 21 and converts it into a first voltage signal; the second electrostatic needle 42 obtains the charge corresponding to the lower beryllium target 22 and converts it into a second voltage signal; the single-chip microcomputer controller 43 receives the first voltage signal to determine the first charge amount corresponding to the upper beryllium target 21, and receives the second voltage signal to determine the second charge amount corresponding to the lower beryllium target 22; the single-chip microcomputer controller 43 adjusts the beam position of the high-energy charged particle beam emitted by the XY bidirectional beam controller 12 based on the first charge amount and the second charge amount.

[0068] In some preferred embodiments, the single-chip microcomputer controller 43 adjusts the beam position of the high-energy charged particle beam emitted by the XY bidirectional beam controller 12 based on the first charge amount and the second charge amount, including: determining the difference between the first charge amount and the second charge amount; when the difference is positive, controlling the beam position of the high-energy charged particle beam emitted by the XY bidirectional beam controller 12 to deflect toward the direction of the lower beryllium target 22; when the difference is negative, controlling the beam position of the high-energy charged particle beam emitted by the XY bidirectional beam controller 12 to deflect toward the direction of the upper beryllium target 21.

[0069] Through the above steps S102 to S110, the purpose of obtaining the charge amount by adjusting the particle accelerator 1 by adjusting the component 4 is achieved by blocking the outward conduction of the charge based on the insulating isolation gasket. This achieves the technical effect of not using multiple expensive detectors to detect neutrons to adjust the particle accelerator 1, but using the cheaper insulating isolation gasket after blocking to detect the charge amount to adjust the particle accelerator 1, effectively saving costs. This further solves the technical problem of the high cost of adjusting the particle accelerator 1 due to the need for at least three expensive detectors to feedback the entire neutron in the related art.

[0070] Example 3

[0071] Based on the above embodiment, the present invention also proposes an optional device implementation method, which includes: a semicircular Be target (metal beryllium target 2), an insulating isolation gasket 3, an electrometer, a single-chip microcomputer controller 43 and an XY bidirectional beam controller 12.

[0072] The insulating isolation gasket 3 electrically insulates the two semicircular Be targets from the overall target tube in the experiment. The semicircular Be targets extract the charge deposited on the beryllium target 2 by the incident high-energy charged particle beam (high-energy proton or D ion beam) through an insulated wire and amplify and conduct it through an electrometer, transmit it to the microcontroller controller 43, and feed back the position information (charge amount) to the XY bidirectional beam controller 12.

[0073] Example 4

[0074] According to an embodiment of the present invention, an optional method implementation is also provided, such as Figure 6 As shown, Figure 6 This is a flow chart of an optional method for controlling the uniformity of the angular distribution of the isotropic thermal neutron radiation field in Example 4 of the present invention.

[0075] Step S1: Adjust the accelerator body 11 to output a high-energy charged particle beam (high-energy proton or D-ion beam), and adjust the high-energy charged particle beam through the XY bidirectional beam controller 12 so that the beam spot of the high-energy proton / D-ion beam is 20 mm to 500 mm;

[0076] Step S2: The high-energy proton / D ion beam bombards two semicircular Be targets (metal beryllium target 2). Since the Be targets are in an electrically insulating state, charge begins to deposit.

[0077] Step S3: the charge deposited on the semicircular Be target is transmitted to the electrometer via an insulated wire, and then amplified and transmitted to the single chip controller 43;

[0078] Step S4, the single chip controller 43 analyzes the charge information on the two Be targets, and when they are equal, does not feed back information to the XY bidirectional beam controller 12;

[0079] Step S5: When the charge information on the two Be targets is not equal, feedback adjustment information is sent to the XY bidirectional beam controller 12;

[0080] Step S6: adjust the XY bidirectional beam controller 12 on the beam line so that the beam spot center of the high energy proton / D ion beam is located at the geometric center of the beam line pipeline.

[0081] Through the above steps S1 to S6, the neutron uniformity control accuracy can be effectively improved while reducing the cost of related equipment.

[0082] The above are only preferred embodiments of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principles of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

Claims

1. A device for controlling the uniformity of the angular distribution of an isotropic thermal neutron radiation field, characterized in that: include: A particle accelerator (1) for emitting a high-energy charged particle beam with a beam position; A beryllium target (2) is placed along the emission line of the high-energy charged particle beam, and the high-energy charged particle beam bombards the beryllium target (2) to generate electric charges; An insulating isolation washer (3) is wound around the outside of the beryllium target (2) to prevent the electric charge from being conducted from the beryllium target (2) to the outside world; An adjustment component (4) is connected to the beryllium target (2) and is used to obtain the amount of charge on the beryllium target (2), and is connected to the particle accelerator (1) and is used to adjust the angle at which the high-energy charged particle beam is emitted toward the beryllium target (2).

2. The isotropic thermal neutron radiation field angle distribution uniformity control device according to claim 1, characterized in that: The particle accelerator (1) comprises an accelerator body (11) and an XY bidirectional beam controller (12); The accelerator body (11) emits the high-energy charged particle beam, and the high-energy charged particle beam is adjusted in beam position by the XY bidirectional beam controller (12); The XY bidirectional beam controller (12) is connected to the adjustment component (4), and the adjustment component (4) is used to control the XY bidirectional beam controller (12) to adjust the beam position of the high-energy charged particle beam.

3. The isotropic thermal neutron radiation field angle distribution uniformity control device according to claim 1, characterized in that: The regulating component (4) includes an electrostatic needle and a single chip microcomputer controller (43); The electrostatic needle is connected to the beryllium target (2), and is used to obtain the charge on the beryllium target (2) and convert the charge into a voltage signal; The electrostatic needle is connected to the single-chip microcomputer controller (43). The single-chip microcomputer controller (43) determines the amount of charge generated on the beryllium target (2) based on the voltage signal and adjusts the angle at which the high-energy charged particle beam is emitted toward the beryllium target (2).

4. The isotropic thermal neutron radiation field angle distribution uniformity control device according to claim 3, characterized in that: The beryllium target (2) comprises an upper beryllium target (21) and a lower beryllium target (22), and the upper beryllium target (21) and the lower beryllium target (22) are both distributed along the line where the high-energy charged particle beam is emitted; A spacing distance is set between the upper beryllium target (21) and the lower beryllium target (22), and the lower edge line of the upper beryllium target (21) and the upper edge line of the upper beryllium target (21) are in the same horizontal plane.

5. The isotropic thermal neutron radiation field angle distribution uniformity control device according to claim 4, characterized in that: The spacing distance between the upper beryllium target (21) and the lower beryllium target (22) is set to at least 50CM.

6. The isotropic thermal neutron radiation field angle distribution uniformity control device according to claim 4, characterized in that: The upper beryllium target (21) and the lower beryllium target (22) are both semicircular pancake-shaped structures, and the orthographic projections of the upper beryllium target (21) and the lower beryllium target (22) form a complete circle.

7. The isotropic thermal neutron radiation field angle distribution uniformity control device according to claim 4, characterized in that: The electrostatic needle comprises a first electrostatic needle (41) and a second electrostatic needle (42); The first electrostatic needle (41) is connected to the upper beryllium target (21) to obtain a first voltage signal corresponding to the upper beryllium target (21); The second electrostatic needle (42) is connected to the lower beryllium target (22) to obtain a second voltage signal corresponding to the lower beryllium target (22); The single chip controller (43) determines a first charge amount corresponding to the upper beryllium target (21) based on the first voltage signal, and determines a second charge amount corresponding to the lower beryllium target (22) based on the second voltage signal; The single chip controller (43) adjusts the angle at which the high energy charged particle beam is directed toward the beryllium target (2) based on the first charge amount and the second charge amount.

8. A method for controlling the uniformity of the angular distribution of an isotropic thermal neutron radiation field, characterized in that: include: The accelerator body (11) emits a high-energy charged particle beam; The high-energy charged particle beam is adjusted in position by an XY bidirectional beam controller (12); Part of the charged particles in the high-energy charged particle beam bombards the upper beryllium target (21), and another part of the charged particles bombards the lower beryllium target (22), generating electric charges, wherein the sum of the charged particles bombarding the upper beryllium target (21) and the charged particles bombarding the lower beryllium target (22) is the total amount of charged particles in the high-energy charged particle beam; A first electrostatic needle (41) acquires the charge on the upper beryllium target (21), and a second electrostatic needle (42) acquires the charge on the lower beryllium target (22); The single chip controller (43) adjusts the beam position of the high energy charged particle beam emitted by the XY bidirectional beam controller (12) based on the charges corresponding to the upper beryllium target (21) and the lower beryllium target (22).

9. The method for controlling the uniformity of the angular distribution of isotropic thermal neutron radiation field according to claim 8, characterized in that: The single chip controller (43) adjusts the beam position of the high energy charged particle beam emitted by the XY bidirectional beam controller (12) based on the charges corresponding to the upper beryllium target (21) and the lower beryllium target (22), including: The first electrostatic needle (41) obtains the charge corresponding to the upper beryllium target (21) and converts it into a first voltage signal; The second electrostatic needle (42) obtains a second voltage signal of a charge conversion position corresponding to the lower beryllium target (22); The single chip controller (43) receives the first voltage signal to determine a first charge amount corresponding to the upper beryllium target (21), and receives the second voltage signal to determine a second charge amount corresponding to the lower beryllium target (22); The single chip controller (43) adjusts the beam position of the high energy charged particle beam emitted by the XY bidirectional beam controller (12) based on the first charge amount and the second charge amount.

10. The method for controlling the uniformity of the angular distribution of isotropic thermal neutron radiation field according to claim 9, characterized in that: The single chip controller (43) adjusts the beam position of the high energy charged particle beam emitted by the XY bidirectional beam controller (12) based on the first charge amount and the second charge amount, including: determining a difference between the first charge amount and the second charge amount; When the difference is a positive value, the XY bidirectional beam controller (12) is controlled to emit a high-energy charged particle beam, and the beam position thereof is deflected toward the lower beryllium target (22); When the difference is a negative value, the XY bidirectional beam controller (12) is controlled to emit a high-energy charged particle beam so that the beam position is deflected toward the upper beryllium target (21).

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