A large-area online neutron detector and detection method

Abstract

The present invention relates to a large-area online neutron detector and a detection method, which comprises: a sealing port for connection is arranged at the end of an outer shell; an inner core of the neutron detector is arranged inside the outer shell; the inner core of the neutron detector comprises a neutron conversion layer, a high-voltage pole, a position pole and an isolation window; a contact end is arranged at the first end of a multi-channel signal output adapter plate, the contact end is inserted into the sealing port on the outer shell and connected to the position pole of one group of the inner core of the neutron detector located in the outer shell; a multi-channel connector is arranged at the second end of the multi-channel signal output adapter plate as a signal output port of a beam profile monitoring detector; the neutron conversion layer adopts a high-voltage pole, a position pole and an isolation window; a multi-channel signal output adapter plate is connected to the inner core of the neutron detector ... 10 B solid, neutrons pass through the neutron conversion layer and 10 B reacts to produce charged particles. When the charged particles pass through the working gas in the ionization chamber, electron-ion pairs are formed. The electrons or ions are collected by adding a high-voltage electric field to the high-voltage pole to obtain a current signal proportional to the number of neutrons.

Description

Technical Field

[0001] The invention relates to the technical field of particle detectors, and in particular to a large-area online neutron detector and a detection method used in the quality diagnosis of a beam in boron neutron capture therapy. Background Art

[0002] Boron Neutron Capture Therapy (BNCT) is a biological targeted radiotherapy that uses neutrons to target 10 B particles and release them after nuclear reactions and thermal neutron capture 10 B particles are used to kill cancer cells. In the 1940s, biophysicist GL Locher proposed the principle and method of boron neutron capture therapy. After injecting special boron-containing compounds that have affinity for tumor cells into cells, the capture reaction between boron and thermal neutrons mainly occurs in the tumor area because boron has a particularly large absorption cross-section for thermal neutrons. After the reaction between boron and neutrons, the energy is deposited in the cell range of 4-9μm, and can be rapidly enriched in tumor cells after thermal neutron irradiation. The absorbed dose in the tumor cell area is much higher than that in normal healthy tissue, so it can kill cancer cells very well without damaging normal cells. This boron-containing carrier compound drug itself is non-toxic to the human body, but when the tumor area containing the boron compound is irradiated by thermal neutrons, a nuclear reaction occurs. 10 B absorbs thermal neutrons and quickly turns into 11 B, then decomposed into 4 He and 7 Li particles, these two particles fly in opposite directions, but in the same straight line. The range of action of particles in the body is about 10μm at the cell level. This reaction constitutes the physical basis of boron neutron capture therapy. Therefore, theoretically, if an ideal boron-containing drug can be found and injected into the human body, boron can be effectively used in the cells of the tumor area. 10 B concentration is higher than that in normal tissue cells 10 B concentration is high, and BNCT treatment of cancer will have good clinical application prospects.

[0003] The alpha particles emitted by the reaction and 7 Li particles have a higher linear energy transfer (LET), which can enhance biological effects and cause greater damage to tissue cells. They have no side effects on normal tissue cells, but have stronger and more destructive power and killing power on tumor cells. However, using this nuclear reaction to treat tumors requires the following two requirements: first, accurate targeting of treatment. 10 The compound drug carrier B is mainly enriched in tumor cells. The emitted neutrons are mainly 10The B carrier compound drug captures the atoms in cancer cells and undergoes nuclear reactions, while the atoms in healthy tissue cells are less captured. Secondly, the treatment causes minor damage to healthy tissues. In human cells, the alpha particles emitted by this nuclear reaction are in the range of about 4μm, and the generated 7 The size of Li particles is 9μm, which is comparable to the size of cells, and can kill cancer cells while protecting normal cells as much as possible.

[0004] However, one of the key technologies for the success of BNCT is the stable output of neutron sources and the online real-time monitoring of neutron beams. At present, the ideal neutron source for BNCT should have epithermal neutrons as its main component, be able to continuously and stably output neutrons for more than one hour, and have a flux density of no less than 10 9 cm -2 s -1 In addition, the maximum value of the incident thermal neutron flux must be within the range of tumor cells to ensure 10 B(n,α) 7 Li reaction can only kill tumor cells without harming other cells. Secondly, the fast neutrons and gamma rays contained in the neutron source should be reduced to a minimum as much as possible to avoid damage to normal tissue cells in the human body. Finally, the neutron beam should have good directionality and collimation stability.

[0005] Currently, the methods used for real-time online uniformity measurement of beam current include the film method, the fluorescent target method, and the ionization chamber scanning method. The traditional film method has limitations such as long time consumption, complex quality control, and equivalent thickness; and for high-intensity beams, the fluorescent equipment in the fluorescent target method may be broken down, and the principle of CCD determines that it cannot be used for long-term measurement under strong radiation conditions. Neither the traditional film method nor the fluorescent target method can be used for real-time monitoring of beam uniformity. The ionization chamber scanning method is currently a widely used measurement method, and its results meet the standards of the International Atomic Energy Agency (IAEA). However, the ionization chamber scanning method on the market cannot achieve on-beam monitoring, and the position resolution is poor. Summary of the invention

[0006] In view of the above problems, the purpose of the present invention is to provide a large-area online neutron detector and detection method, which can realize real-time monitoring and diagnosis of beam quality during treatment; it has the ability to resolve neutron beam position information and can accurately and quickly realize real-time on-beam monitoring of neutron beam quality diagnosis.

[0007] To achieve the above-mentioned purpose, the present invention adopts the following technical scheme: a large-area online neutron detector, comprising: an outer shell, which is a gas-sealed cavity, and a sealing port for connection is arranged at the end; a neutron detector core, which is arranged in at least two groups, both of which are arranged inside the outer shell; each group of the neutron detector cores includes a neutron conversion layer, a high-voltage pole and a position pole; a multi-channel signal output adapter board, which is arranged in at least two groups, and the first end of each of the multi-channel signal output adapter boards is provided with a contact end, which is inserted into the sealing port on the outer shell and connected to the position pole of one group of the neutron detector cores located in the outer shell; the second end of the multi-channel signal output adapter board is provided with a multi-channel connector as a signal output port of the beam profile monitoring detector; the neutron conversion layer adopts 10 B solid, the number of layers is adjusted according to the signal size; neutrons pass through the neutron conversion layer and 10 B reacts to produce charged particles. When the charged particles pass through the working gas in the ionization chamber, the gas molecules are ionized to form electron-ion pairs. The number of electron-ion pairs is proportional to the energy loss of the neutrons in the ionization chamber. The electrons or ions are collected by adding a high-voltage electric field to the high-voltage pole to obtain a current signal proportional to the number of neutrons; the absolute current intensity value is obtained by calibrating with a known beam current intensity.

[0008] Furthermore, the working gas is Ar-CO2, Ar-C4H 10 Or Ar-CH4 mixed gas.

[0009] Furthermore, the housing is made of aluminum material, and comprises a main frame, and an incident window and an exit window located on the main frame.

[0010] Furthermore, the neutron detector further comprises an isolation window, which is located between the outer shell and the inner core of the ionization chamber and is sealed outside the inner core of the ionization chamber.

[0011] Furthermore, the thickness of the neutron conversion layer is set according to the detection efficiency and the neutron scattering rate.

[0012] Furthermore, the high voltage pole is composed of a conductive film and a PCB frame with a conductive electrode, and the conductive film is laid on the PCB frame.

[0013] Furthermore, the position pole is made of a hard PCB board, and the hard PCB board is plated with a plurality of position signal strips arranged in parallel;

[0014] The directions of the position signal bars on the two position poles in the inner cores of the two groups of neutron detectors are perpendicular to each other.

[0015] Furthermore, the isolation window includes an aluminum alloy isolation window frame, and a single-sided aluminum-plated Mylar film adhered to the aluminum alloy isolation window frame by conductive adhesive.

[0016] Furthermore, the contact end of the multi-channel signal output adapter board is composed of a plurality of signal output strips, and the first ends of the signal output strips are connected to the position signal strips on the position poles in a one-to-one correspondence.

[0017] A detection method based on the above-mentioned large-area online neutron detector comprises: placing the neutron detector vertically in the direction of the neutron beam for irradiation; controlling the gas flow system through a gas flow controller to fill the neutron detector with working gas; interconnecting the multi-channel connector on the neutron detector with a subsequent acquisition system; simultaneously acquiring beam dose signals obtained from each position signal strip of the position pole on the inner core of the neutron detector; making a one-to-one correspondence between the dose information obtained on each position signal strip and the position of the position pole in the neutron detector to obtain the dose distribution of the entire irradiated neutron beam in a two-dimensional position; calculating the uniformity of the irradiation distribution of the neutron beam according to the obtained irradiated neutron beam dose distribution in the X and Y directions to obtain real-time monitoring beam position information.

[0018] The present invention adopts the above technical solution, which has the following advantages:

[0019] 1. The detector of the present invention can realize online monitoring of neutron beams, can observe the spatial position of neutrons in real time, can well grasp the dose distribution of the beam for clinical treatment, and is more helpful to implement different plans for patients.

[0020] 2. The detector of the present invention can set the coating thickness of the neutron conversion layer according to different requirements of detection efficiency and neutron scattering rate. The coating thickness of the neutron conversion layer of the detector can be 0.5μm~10μm, and at the same time, the probability of neutron scattering is less than one in one hundred thousand. The influence of the detector on the performance of the beam is almost negligible. The measurement result can be used as a real-time monitoring of the beam quality and can protect and ensure the beam quality of the machine; it is very important for quality assurance of particle therapy devices.

[0021] 3. The detection system of the present invention can accurately measure the beam position to the millimeter level, which can fully meet the requirements for most neutron beam quality diagnosis and monitoring. At the same time, the gas flow mode adopted by the detection system can better meet engineering applications, adapt to more measurement environments, and reduce the impact of the external environment on the detector performance.

[0022] 4. The effective area of ​​the detector of the present invention can be installed according to different specific needs to achieve high efficiency and high accuracy.

[0023] 5. The beam dose distribution real-time measurement system of the present invention obtains the information of incident neutrons by using the position stripes of the secondary charged particles monitored on the signal electrode, and the signal electrodes in the two groups of ionization chambers in the inner core of the neutron detector are perpendicular to each other, thereby obtaining the neutron beam distribution information in the X and Y directions. At the same time, the two-dimensional dose distribution of neutrons is obtained by calculating the signal output to achieve the purpose of real-time measurement. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1a is a schematic diagram of the overall structure of a neutron detector in one embodiment of the present invention;

[0025] Figure 1b is a side view of the overall structure of a neutron detector in one embodiment of the present invention;

[0026] Figure 2 is a schematic diagram of the structure of a neutron conversion layer in one embodiment of the present invention;

[0027] Figure 3 is a neutron energy distribution diagram in one embodiment of the present invention;

[0028] Figure 4 Schematic diagram of the overall system of a neutron detector in one embodiment of the present invention. DETAILED DESCRIPTION

[0029] In order to make the purpose, technical solution and advantages of the embodiment of the present invention clearer, the technical solution of the embodiment of the present invention will be clearly and completely described below in conjunction with the drawings of the embodiment of the present invention. Obviously, the described embodiment is a part of the embodiment of the present invention, not all of the embodiments. Based on the described embodiment of the present invention, all other embodiments obtained by ordinary technicians in this field belong to the scope of protection of the present invention.

[0030] It should be noted that the terms used herein are only for describing specific embodiments and are not intended to limit the exemplary embodiments according to the present application. As used herein, unless the context clearly indicates otherwise, the singular form is also intended to include the plural form. In addition, it should be understood that when the terms "comprise" and / or "include" are used in this specification, it indicates the presence of features, steps, operations, devices, components and / or combinations thereof.

[0031] The large-area online neutron detector and detection method provided by the present invention are mainly used for beam quality diagnosis in boron neutron capture therapy, and can perform beam quality diagnosis and monitoring on parameters such as the flatness, symmetry, and irradiation position of the neutron beam, thereby realizing real-time online diagnosis of the beam in boron neutron capture therapy. Real-time monitoring and diagnosis of beam quality during treatment are realized; the beam position information has the ability to be resolved, and real-time on-beam monitoring of beam quality diagnosis can be accurately and quickly realized. The detector is mainly composed of an outer shell 1, a neutron detector core 2, and a multi-channel signal output connection plate 3. Among them, the outer shell 1 is made of aluminum alloy, and a sealing groove is designed at each opening position, and the inside of the detector is isolated from the atmosphere by a rubber ring in the sealing groove; the neutron detector core 2 of the detector is composed of two groups of neutron detector cores 2, and the neutron detector core 2 is composed of a neutron conversion layer 2-1, a high-voltage pole 2-2, a position pole 2-3, and an isolation window 2-4. The neutron conversion layer 2-1 is composed of a 0.5μm-10μm thick 10 B is a solid coating, and the neutron beam passing through it reacts with the conversion layer material to produce charged particles. 7 The isolation window 2-4 uses conductive glue to stick a 7μm-25μm thick single-sided aluminum-plated Mylar film to the aluminum alloy isolation window frame, which can shield external electromagnetic interference; the position poles 2-3 of the two groups of ionization chambers in the neutron detector core 2 are respectively connected to the multi-channel signal output adapter board 3 to output the signal output port of the neutron beam current monitoring detector.

[0032] In one embodiment of the present invention, a large-area online neutron detector is provided. In this embodiment, Figure 1a to Figure 2 As shown, the neutron detector comprises:

[0033] The housing 1 is a gas-tight chamber, and a sealing port for connection is provided at the end thereof;

[0034] The neutron detector inner core 2 is provided in at least two groups, both of which are provided inside the outer shell 1 and form an ionization chamber with the outer shell 1; each group of the neutron detector inner core 2 includes a neutron conversion layer 2-1, a high-voltage electrode 2-2 and a position electrode 2-3;

[0035] At least two multi-channel signal output adapter boards 3 are provided, and a contact terminal 3-1 is provided at the first end of each multi-channel signal output adapter board 3, and the contact terminal 3-1 is inserted into the sealing opening on the shell 1 and connected to the position pole 2-3 of one group of neutron detector inner cores 2 located in the shell 1; a multi-channel connector 3-2 is provided at the second end of the multi-channel signal output adapter board 3 as a signal output port of the beam profile monitoring detector;

[0036] Among them, the neutron conversion layer 2-1 adopts 10B is made of solid, and the number of layers can be adjusted according to the signal size to achieve the requirement of increasing the output signal size.

[0037] When in use, neutrons pass through the neutron conversion layer 2-1 and 10 B reacts to produce charged particles. When the charged particles pass through the working gas in the ionization chamber formed by the outer shell 1 and the inner core 2 of the neutron detector, the gas molecules are ionized to form electron-ion pairs. The number of electron-ion pairs is proportional to the energy loss of the neutrons in the ionization chamber. By adding a high-voltage electric field to the high-voltage electrode 2-2, electrons or ions are collected to obtain a current signal proportional to the number of neutrons. The absolute current value can be obtained by calibrating with a known beam current intensity.

[0038] In the above embodiment, a detector is used to monitor the beam position and half-height full width, which requires vacuum isolation and filling with working gas. The working gas filled in the ionization chamber is Ar-CO2, Ar-C4H 10 Or Ar-CH4 mixed gas. Ar gas can obtain very low working voltage and can obtain avalanche discharge under low field strength. 10 and CH4 as quenching gas, mainly suppressing discharge phenomenon, increasing the average atomic number and density of the gas, and making the gas work under a higher magnification. The invention is a detector system capable of monitoring the beam position in real time and having no substantial influence on the performance of the beam.

[0039] In the above embodiment, the housing 1 is a protective support component, made of aluminum material, and includes a main frame 1-1, and an incident window 1-2 and an exit window 1-3 located on the main frame 1-1. In the working state, the interior is in a sealed state, and the sealing openings are provided with sealing grooves, and the interior of the detector is isolated from the atmosphere by a rubber ring in the sealing groove to achieve sealing.

[0040] In the above embodiment, in order to improve the detection efficiency of the neutron detector, the neutron conversion layer 2-1 is made of concentrated high-purity solid 10 B is used as a neutron sensitive layer, with a content of more than 90%; when used, it is concentrated 10 Solid B causes neutrons to undergo a nuclear reaction with the conversion layer material, which produces charged particles 7 Li and α particles; at the same time, the thickness of the neutron conversion layer 2-1 can be optimized according to the detection efficiency and the neutron scattering rate to meet the requirements of the output signal. In this embodiment, the thickness of the neutron conversion layer 2-1 is 0.5μm-10μm.

[0041] In the above embodiment, the high voltage electrode 2-2 is composed of a conductive film and a PCB frame with a conductive electrode, and the conductive film is laid on the PCB frame. Among them, the effective area of ​​the conductive film is 30×30mm 2~500×500mm 2 .

[0042] In the above embodiment, the position pole 2-3 is made of a hard PCB board, and the hard PCB board is plated with a plurality of parallel position signal strips 2-3-1. In this embodiment, the effective area of ​​the hard PCB board is 30×30 mm. 2 ~500×500mm 2 , thickness is 0.1mm~2mm; the position signal strips 2-3-1 are preferably plated with 20~100 strips, each strip is 0.5~5mm wide, and the spacing between adjacent position signal strips 2-3-1 is 0.1~1mm.

[0043] The directions of the position signal strips 2 - 3 - 1 on the two position poles 2 - 3 in the inner cores 2 of the two groups of neutron detectors are perpendicular to each other.

[0044] When in use, since the position pole 2-3 adopts a strip structure, the projection distribution of the beam profile can be given. Using the basic principle of the ionization chamber, the position pole 2-3 of the ionization chamber is divided into strips and read out separately, so that the ionization chamber has the function of measuring the beam position and the vertical and horizontal projection. At the same time, the ionization chamber has little effect on the beam, and is a penetrating detector that can be used for real-time monitoring.

[0045] The above embodiment further includes an isolation window 2-4. The isolation window 2-4 is located between the housing 1 and the neutron detector inner core 2, and is sealed outside the neutron detector inner core 2 to play a role in sealing and shielding interference.

[0046] The isolation window 2-4 includes an aluminum alloy isolation window frame and a single-sided aluminum-plated Mylar film attached to the aluminum alloy isolation window frame by conductive adhesive. In this embodiment, the thickness of the aluminum-plated Mylar film is preferably 7 μm-25 μm to achieve the purpose of shielding external electromagnetic noise interference.

[0047] In the above embodiment, the contact end 3-1 of the multi-channel signal output adapter board 3 is composed of 20 to 100 signal output bars, and the first end of the signal output bar is connected one-to-one with the position signal bar 2-3-1 on the position pole 2-3 to realize real-time output of two-dimensional position information.

[0048] In summary, the detector of the present invention uniformly applies boron in the form of a solid coating on the inner core 2 of the double-sided epoxy film of the neutron detector, and can perform real-time monitoring and diagnosis of the neutron beam quality information. The present invention is based on the interaction between the neutron beam and the boron-coated film to produce nuclear reactions to generate alpha particles and 7 The detector can accurately and quickly realize real-time online monitoring and diagnosis of neutron beam uniformity, and the neutron scattering rate is less than one in 100,000 (such as Figure 3As shown in Figure 2, the neutron conversion layer does not have a substantial effect on the performance of the beam. For example, when the energy is 10 keV and the intensity is 10 9 cm -2 *s -1 The thickness of the neutron conversion layer 2-1 is 3 μm, and the effective area is 100*100 mm. The average energy of the signal output α particles measured on the position pole 2-3 is 0.773 MeV. 7 The average energy of Li is 0.360 MeV.

[0049] In the boron neutron capture therapy of the present invention, the detector can diagnose the flatness, symmetry and other parameters of the beam in the axial direction, realizing real-time monitoring and diagnosis of the beam quality during the treatment process; it has the ability to resolve the beam position information, and can accurately and quickly realize real-time on-beam monitoring of beam quality diagnosis.

[0050] In one embodiment of the present invention, a detection method of a large-area online neutron detector is provided, such as Figure 4 As shown, it includes the following steps:

[0051] 1) Turn on the high-voltage system and place the neutron detector vertically in the direction of the neutron beam for irradiation;

[0052] 2) Turn on the gas flow system and fill the neutron detector with working gas through the gas flow controller;

[0053] In this embodiment, the flow rate of the working gas is 0.01-0.02 mbar / s, the pressure is 5-10 mbar greater than the ambient pressure, and the flow rate is kept constant to continuously update the gas;

[0054] 3) connecting the multi-channel connector 3-2 on the neutron detector to the subsequent acquisition system; and simultaneously acquiring the beam dose signal obtained from each position signal strip 2-3-1 of the position pole 2-3 on the neutron detector inner core 2 of the neutron detector;

[0055] 4) The dose information obtained on each position signal strip 2-3-1 is matched to the position of the position pole 2-3 in the neutron detector one by one, and the dose distribution of the entire irradiation neutron beam in the two-dimensional position is obtained;

[0056] 5) According to the obtained neutron beam dose distribution in the X and Y directions, the uniformity of the neutron beam irradiation distribution is calculated, thereby obtaining real-time monitoring beam position information.

[0057] The method provided in this embodiment is based on the above-mentioned structural embodiments. Please refer to the above-mentioned embodiments for specific details, which will not be repeated here.

[0058] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A large-area online neutron detector for online monitoring of neutron dose distribution in boron neutron capture therapy, characterized in that: include: The housing is a gas-tight chamber, and a sealing port for connection is provided at the end thereof; The neutron detector inner core is provided in at least two groups, both of which are provided inside the outer shell and form an ionization chamber with the outer shell; each group of the neutron detector inner core includes a neutron conversion layer, a high voltage electrode and a position electrode; At least two multi-channel signal output adapter boards are provided, and a contact end is provided at the first end of each of the multi-channel signal output adapter boards, and the contact end is inserted into the sealing opening on the shell and connected to the position pole of one group of the neutron detector inner cores in the shell; a multi-channel connector is provided at the second end of the multi-channel signal output adapter board as a signal output port of the beam profile monitoring detector; The neutron conversion layer adopts 10 B is made of solid, and the number of layers is adjusted according to the signal size; Neutrons pass through the neutron conversion layer and 10 B reacts to produce charged particles. When the charged particles pass through the working gas in the ionization chamber, the gas molecules are ionized to form electron-ion pairs. The number of electron-ion pairs is proportional to the energy loss of the neutrons in the ionization chamber. The electrons or ions are collected by applying a high-voltage electric field to the high-voltage pole to obtain a current signal proportional to the number of neutrons. The absolute current value is obtained by calibrating with a known beam current intensity. The working gas filled in the ionization chamber is Ar-CO2, Ar-C4H 10 or Ar-CH4 mixed gas; by mixing Ar and quenching gas, the electron ion pairs in the sensitive volume of the ionization chamber are multiplied; The position pole is made of a hard PCB board, and a plurality of position signal strips arranged in parallel are plated on the hard PCB board; The directions of the position signal strips on the two position poles in the inner cores of the two groups of neutron detectors are perpendicular to each other; The effective area of ​​the rigid PCB is 30×30 mm 2 ~500×500mm 2 .

2. The large-area online neutron detector according to claim 1, characterized in that: The housing is made of aluminum material and comprises a main frame, and an incident window and an exit window located on the main frame.

3. The large-area online neutron detector according to claim 1, characterized in that: The neutron detector further comprises an isolation window, which is located between the outer shell and the inner core of the neutron detector and is sealed outside the inner core of the neutron detector.

4. The large-area online neutron detector according to claim 1, characterized in that: The thickness of the neutron conversion layer is set according to the detection efficiency and the neutron scattering rate.

5. The large-area online neutron detector according to claim 1, characterized in that: The high voltage electrode is composed of a conductive film and a PCB frame with a conductive electrode, and the conductive film is laid on the PCB frame.

6. The large-area online neutron detector according to claim 3, characterized in that: The isolation window comprises an aluminum alloy isolation window frame and a single-sided aluminum-plated Mylar film adhered to the aluminum alloy isolation window frame by conductive adhesive.

7. The large-area online neutron detector according to claim 1, characterized in that: The contact end of the multi-channel signal output adapter board is composed of a plurality of signal output strips, and the first ends of the signal output strips are connected to the position signal strips on the position poles in a one-to-one correspondence.

8. A detection method based on the large-area online neutron detector according to any one of claims 1 to 7, characterized in that: include: The neutron detector is placed vertically in the direction of the neutron beam for irradiation; The gas flow system is controlled by a gas flow controller to fill the neutron detector with working gas; Connecting the multi-channel connector on the neutron detector to the subsequent acquisition system; and simultaneously acquiring the beam dose signal obtained from each position signal strip on the position pole of the neutron detector inner core; The dose information obtained on each position signal strip is matched to the position of the position pole in the neutron detector one by one, so as to obtain the dose distribution of the entire irradiation neutron beam in the two-dimensional position; According to the obtained irradiation neutron beam dose distribution in the X and Y directions, the uniformity of the neutron beam irradiation distribution is calculated, and the real-time monitoring beam position information is obtained.

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