A method and apparatus for locating incident neutrons using a neutron detector, a computing device, and a storage medium

Abstract

The application discloses a method and device for realizing incident neutron positioning by using a neutron detector, a computing device and a storage medium. The method comprises the following steps: obtaining a neutron detector with a boron-coated scintillation crystal with a boron-coated film by performing boron-coated film treatment on the surface of the scintillation crystal of the neutron detector; after obtaining the neutron detector with the boron-coated scintillation crystal with the boron-coated film, collecting pulse waveform data of each channel of the neutron detector according to a trigger signal generated by each event, and calculating a charge ratio of the pulse waveform data of each channel of each event by using a charge integration method; determining whether each event is a neutron event or a gamma event by using the charge ratio of the pulse waveform data of each channel of each event; and when the event is determined to be a neutron event, calculating an incident position of the neutron when the neutron event occurs by using a two-dimensional Gaussian distribution method of a photon response function.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of radiation detection technology, in particular to a method and device for positioning incident neutrons by a neutron detector, a computing device and a storage medium. BACKGROUND

[0002] In recent years, neutron detection technology has developed rapidly in the fields of high-intensity neutron sources, material structure, nanoscience, condensed matter physics, space physics, and has extremely important significance in the industrial directions of nuclear medical radiation therapy, aerospace and industrial applications, nuclear power plant safety detection systems, environmental monitoring systems, nuclear explosion and hidden nuclear material detection. Such detectors usually have the advantages of high count rate, high detection efficiency, high position resolution and high neutron / gamma suppression ratio.

[0003] Traditional 3 He gas neutron detector is the most commonly used and mature neutron detection method at present, because 3 He is not easy to seal in solid state under normal circumstances, and its supply is limited by the United States, and its price is very expensive, so it is urgent to develop other types of neutron detectors to replace the traditional 3 He neutron detector. The main neutron detector that can replace 3 He at present is a scintillator detector. The scintillator detector has the advantages of low cost, high detection efficiency, simple structure, stable performance, etc., and has been widely studied and applied in neutron detection. The scintillator neutron detector is mainly based on nuclear reaction method, which generates charged particles through the interaction of neutrons and neutron-sensitive materials, and the fluorescence generated in the scintillator is used to indirectly measure neutrons.

[0004] In recent years, GAGG (Gallium Germanium Arsenide Gallium, cerium-doped gadolinium gallium aluminum garnet) scintillation crystal has gradually become a popular material for neutron detectors due to its high neutron reaction cross section, high light yield, short light emission decay time, non-hydration, high density and high energy resolution. The traditional method directly uses GAGG crystal to realize neutron detection. Because a large number of gamma rays are accompanied in the process of measuring neutrons, the GAGG crystal is also very sensitive to gamma rays, it is difficult to realize neutron / gamma discrimination, and the neutron detection efficiency is also relatively low. SUMMARY

[0005] The present application provides a method and device for positioning incident neutrons by a neutron detector, a computing device and a storage medium, in order to solve the technical problems of how to realize neutron / gamma discrimination and how to improve the detection efficiency of neutrons.

[0006] The present application provides a method for positioning incident neutrons by a neutron detector, comprising:

[0007] The neutron detector with boron-coated scintillation crystal is obtained by boron coating film treatment on the surface of the scintillation crystal of the neutron detector;

[0008] After obtaining the neutron detector with boron-coated scintillation crystal, the pulse waveform data of each channel of the neutron detector is collected according to the trigger signal generated by each event, and the charge ratio of the pulse waveform data of each channel of each event is calculated by using the charge integration method;

[0009] The charge ratio of the pulse waveform data of each channel of each event is used to determine whether each event is a neutron event or a gamma event;

[0010] When the event is determined to be a neutron event, the incident position of the neutron when the neutron event occurs is calculated by using the two-dimensional Gaussian distribution method of the photon response function.

[0011] Preferably, the neutron detector with boron-coated scintillation crystal obtained by boron coating film treatment on the surface of the scintillation crystal of the neutron detector comprises:

[0012] The boron-coated scintillation crystal neutron detector with boron coating layer is formed by boron coating film treatment on the surface of the scintillation crystal through electrostatic spraying process; or

[0013] The boron-coated scintillation crystal neutron detector with boron coating layer is obtained by depositing boron carbide B4C or boron oxide B2O3 film on the surface of the scintillation crystal by direct current magnetron sputtering.

[0014] Preferably, the pulse waveform data of each channel of the neutron detector is collected according to the trigger signal generated by each event, and the charge ratio of the pulse waveform data of each channel of each event is calculated by using the charge integration method.

[0015] The sum pulse waveform data of each event is calculated according to the pulse waveform data of each channel of the neutron detector generated by each event;

[0016] The sum pulse waveform data of each event is segmented to obtain two pieces of sum pulse waveform data, and the charge amount of each piece of sum pulse waveform data is calculated by using the charge integration method;

[0017] The charge ratio of the pulse waveform data of each channel of each event is obtained according to the charge amount of each piece of sum pulse waveform data.

[0018] Preferably, the charge ratio of the pulse waveform data of each channel of each event is used to determine whether each event is a neutron event or a gamma event.

[0019] The charge ratio distribution diagram of all events is formed by statistical processing of the charge ratio of the pulse waveform data of each channel of each event.

[0020] According to the charge ratio distribution of all events, a charge ratio threshold value for judging neutron events and gamma events is determined, and each event is judged as a neutron event or a gamma event according to the charge ratio threshold value.

[0021] Preferably, the judging each event as a neutron event or a gamma event according to the charge ratio threshold value comprises:

[0022] If the charge ratio of the pulse waveform data of each channel of the event is greater than the charge ratio threshold value, the event is judged as a neutron event.

[0023] If the charge ratio of the pulse waveform data of each channel of the event is not greater than the charge ratio threshold value, the event is judged as a gamma event.

[0024] Preferably, the calculating the incident position of the neutron when the neutron event occurs by using the two-dimensional Gaussian distribution method of the photon response function comprises:

[0025] According to the photon intensity generated by the nuclear reaction of the neutron at the incident position of the neutron, a Gaussian distribution expression of two-dimensional photon intensity is constructed.

[0026] The incident position of the neutron when the neutron event occurs is obtained by a series of matrix transformation and matrix solution processing on the Gaussian distribution expression of two-dimensional photon intensity.

[0027] Preferably, the Gaussian distribution expression of two-dimensional photon intensity comprises:

[0028]

[0029] Wherein, Q xi,yi are the photon intensities collected by the i-th row and i-th column silicon photomultiplier SiPM respectively; σ x and σ y are the photon distribution broadening in the x direction and y direction respectively; Q b is the background photon intensity and noise; x i and y i are the row position and column position of each SiPM pixel respectively; x0 and y0 are the row position and column position of the real incident neutron respectively; and A is the real light intensity.

[0030] The embodiment of the present application also provides a device for realizing the positioning of incident neutrons by a neutron detector, which comprises:

[0031] A boron film plating processing module is configured to obtain a neutron detector with a boron-coated scintillation crystal by performing boron film plating processing on the surface of the scintillation crystal of the neutron detector.

[0032] A neutron determining module is configured to, after obtaining the neutron detector with the boron-coated scintillation crystal with the boron film, collect pulse waveform data of each channel of the neutron detector according to a trigger signal generated by each event, and calculate a charge ratio of the pulse waveform data of each channel of each event by using a charge integration method; and determine whether each event is a neutron event or a gamma event by using the charge ratio of the pulse waveform data of each channel of each event.

[0033] A neutron positioning module is configured to, when determining that the event is a neutron event, calculate an incident position of the neutron when the neutron event occurs by using a two-dimensional Gaussian distribution method of a photon response function.

[0034] The embodiment of the present application also provides a computing device, which comprises:

[0035] a memory and a processor;

[0036] The memory is configured to store computer executable instructions, and the processor is configured to execute the computer executable instructions, so that the steps of the method for positioning the incident neutron by using the neutron detector are implemented.

[0037] The embodiment of the present application also provides a computer readable storage medium, which stores computer executable instructions, and the computer executable instructions are executed by the processor, so that the steps of the method for positioning the incident neutron by using the neutron detector are implemented.

[0038] The embodiment of the present application also provides a computer readable storage medium, which stores computer executable instructions, and the computer executable instructions are executed by the processor, so that the steps of the method for positioning the incident neutron by using the neutron detector are implemented. BRIEF DESCRIPTION OF DRAWINGS

[0039] Figure 1 is a flowchart of the method for positioning the incident neutron by using the neutron detector provided by the present application.

[0040] Figure 2 This is a schematic diagram of a device for locating incident neutrons using a neutron detector provided by the present invention;

[0041] Figure 3 This is a schematic diagram of the neutron detector structure provided by the present invention;

[0042] Figure 4 This is a schematic diagram of the charge ratio distribution provided by the present invention;

[0043] Figure 5 This is a structural block diagram of a computing device provided by the present invention. Detailed Implementation

[0044] It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention. In the following description, suffixes such as "module," "part," or "unit" used to denote elements are used only for the purpose of illustrative purposes and have no inherent meaning. Therefore, "module," "part," or "unit" may be used interchangeably.

[0045] This invention relates to a neutron detector method based on SiPM (Silicon Photomultiplier) readout of boron-coated GAGG crystals (continuous crystals or crystal arrays), employing DC magnetron sputtering to deposit a nearly 1 μm thick layer of... 10 A B4C thin film is deposited on the surface or side of a GAGG crystal, with a crystal thickness of approximately 1 mm (no specific limitation). A new generation of silicon photomultiplier tube (SiPM) array is used as the photoelectric converter. A light guide can be added between the crystal and the SiPM, and the crystal, light guide, and SiPM array are coupled through silicone oil. This invention uses an innovative photon response function method to calculate neutron incident location and achieves neutron gamma discrimination through charge integration. The neutron detector provided by the embodiments of this invention can achieve high detection efficiency, high neutron gamma discrimination ratio, and high position resolution at low cost.

[0046] GAGG crystal is a cerium-doped gadolinium aluminum gallium garnet crystal with characteristics such as high light output, fast decay, high energy resolution and high density. It is widely used in high-energy physics, nuclear medicine imaging and the detection of ionizing radiation in industry.

[0047] Figure 1 This is a flowchart of a method for locating incident neutrons using a neutron detector provided by the present invention, as shown below. Figure 1 As shown, it includes:

[0048] Step S101: A neutron detector with a boron-coated scintillation crystal is obtained by depositing a boron film on the surface of the scintillation crystal of the neutron detector.

[0049] In the embodiment of the present application, the neutron detector with boron-coated scintillation crystal with boron-coated film on the surface of the scintillation crystal of the neutron detector is obtained by boron-coated film treatment.

[0050] The boron-coated scintillation crystal neutron detector with boron-coated film is obtained by boron-coated film treatment on the surface of the scintillation crystal through electrostatic spraying process, to form a boron-coated scintillation crystal with boron coating; or

[0051] The boron-coated scintillation crystal neutron detector with boron-coated film is obtained by depositing a thin film of boron carbide B4C or boron oxide B2O3 on the surface of the scintillation crystal through direct current magnetron sputtering.

[0052] The neutron detector system in the embodiment of the present application includes a trigger signal module, a sampling module and a processing module. The trigger signal module is used to generate a trigger signal. The sampling module is used to sample pulse waveform data of each channel of the neutron detector according to the trigger signal. The processing module is used to execute a method for positioning incident neutrons by the neutron detector. The trigger signal module determines whether to generate a trigger signal according to a characteristic signal output by the neutron detector itself, such as a sum signal after adding each channel, or a dynode signal output by the photodetector.

[0053] As shown in Figure 3 The neutron detector structure includes a scintillation crystal, a boron-coated film, a photodetector and a light guide. The scintillation crystal is treated with a boron-coated film. Specifically, the scintillation crystal needs to form a boron coating on the surface of the crystal through electrostatic spraying process, or deposit a 1 μm thick B4C or B2O3 thin film on the surface of the crystal by direct current magnetron sputtering, as shown in Figure 3 .

[0054] In the embodiment of the present application, when the dynode signal of the photodetector exceeds the set threshold to generate a square wave signal, the square wave signal is used as the trigger signal for neutron detector acquisition. The first falling edge or rising edge of the trigger signal is used as the starting time of the number of pulses, and the waveform sampling data of each channel of the neutron detector is started to be sampled, so that the waveform sampling data contains the statistical period.

[0055] In the embodiments of the present application, the boron-containing film includes but is not limited to boron oxide (B2O3), boron carbide (B4C), etc.; the photoelectric detector array can be replaced by a position sensitive photo-multiplier tube (PSPMT), a micro channel plate (MCP), an avalanche photo diode (APD) array, a silicon photo-multiplier (SiPM), a multi-pixel photon counter (MPPC), or a photo-multiplier tube (PMT); the coupling material includes but is not limited to a reflective film, air, and optical glue; and the scintillation crystal includes but is not limited to GAGG and GS20, etc.

[0056] Step S102: After obtaining the neutron detector with the boron-coated scintillation crystal having the boron-plated film, pulse waveform data of each channel of the neutron detector is collected according to a trigger signal generated by each event, and a charge ratio of the pulse waveform data of each channel of each event is calculated by using a charge integration method.

[0057] In the embodiments of the present application, the collecting of the pulse waveform data of each channel of the neutron detector according to the trigger signal generated by each event and the calculation of the charge ratio of the pulse waveform data of each channel of each event by using the charge integration method include:

[0058] The pulse waveform data of each channel of the neutron detector is collected according to the trigger signal generated by each event, and sum pulse waveform data of each event is calculated.

[0059] The sum pulse waveform data of each event is processed by segmentation to obtain two pieces of sum pulse waveform data, and the charge amount of each piece of sum pulse waveform data is calculated by using the charge integration method.

[0060] The charge ratio of the pulse waveform data of each channel of each event is obtained according to the charge amount of each piece of sum pulse waveform data.

[0061] Step S103: The charge ratio of the pulse waveform data of each channel of each event is used to determine whether each event is a neutron event or a gamma event.

[0062] In the embodiments of the present application, the determination of whether each event is a neutron event or a gamma event by using the charge ratio of the pulse waveform data of each channel of each event includes:

[0063] The charge ratio of the pulse waveform data of each channel of the event is statistically processed to form a charge ratio distribution diagram of all events.

[0064] According to the charge ratio distribution diagram of all events, a charge ratio threshold value for judging neutron events and gamma events is determined, and each event is judged to be a neutron event or a gamma event according to the charge ratio threshold value.

[0065] That is, the neutron-gamma discrimination method in the embodiment of the present application mainly uses pulse shape to realize neutron-gamma discrimination. The neutron-gamma discrimination is realized by using the charge integration method, which specifically includes:

[0066] 1) The sum pulse signal of each event is first obtained, and then the sum pulse signal is divided into two segments, and the charge ratio of the two integration intervals is calculated by using the charge integration method;

[0067] The charge ratio (R = I t2 / (I t1 +I t2 )) of the two integration intervals is calculated, where R is the charge ratio; I t1 is the charge value obtained by integrating the pulse amplitude with respect to time from the pulse starting point to t1; and I t2 is the charge value obtained by integrating the pulse amplitude with respect to time from the pulse t1 to the pulse tail.

[0068] 2) The charge ratios of all events are statistically processed to obtain a charge ratio distribution diagram of all events, as shown in Figure 4 .

[0069] 3) The neutron events and the gamma events are identified based on the charge ratio distribution diagram of all events.

[0070] As shown in Figure 4 , the position of the red vertical line is the charge ratio threshold value n, the events to the left of the red vertical line are judged to be gamma events, and the events to the right of the red vertical line are judged to be neutron events.

[0071] In the embodiment of the present application, the determination of each event as a neutron event or a gamma event according to the charge ratio threshold value includes: if the charge ratio of the pulse waveform data of each channel of the event is greater than the charge ratio threshold value, the event is determined to be a neutron event; and if the charge ratio of the pulse waveform data of each channel of the event is not greater than the charge ratio threshold value, the event is determined to be a gamma event.

[0072] Step S104: When the event is determined to be a neutron event, a two-dimensional Gaussian distribution method of a photon response function is used to calculate the incident position of the neutron when the neutron event occurs.

[0073] In the embodiment of the present application, the method for calculating the incident position of the neutron when the neutron event occurs includes:

[0074] According to the photon intensity generated by the nuclear reaction of the neutron at the neutron incident position, a Gaussian distribution expression of two-dimensional photon intensity is constructed.

[0075] Through a series of matrix transformation and matrix solution of the Gaussian distribution expression of two-dimensional photon intensity, the incident position of the neutron when the neutron event occurs is obtained.

[0076] In the embodiment of the present application, the Gaussian distribution expression of two-dimensional photon intensity includes:

[0077]

[0078] Wherein, Q xi,yi is the photon intensity collected by the i-th row and i-th column silicon photomultiplier (SiPM); σ x and σ y are the photon distribution broadening in the x direction and y direction, respectively; Q b is the background photon intensity and noise; x i and y i are the row position and column position of each SiPM pixel, respectively; x0 and y0 are the row position and column position of the real neutron incident, respectively; and A is the real light intensity.

[0079] The incident neutron positioning method specifically includes:

[0080] The positions in the X and Y directions are calculated by the two-dimensional Gaussian distribution method of the photon response function. First, the photon intensity Q xi,yi generated by the nuclear reaction of the neutron at the (x0, y0) position is modeled into a two-dimensional Gaussian distribution (i.e., the Gaussian distribution expression of two-dimensional photon intensity) Then, the real position of the neutron event is obtained by performing the above Gaussian fitting on the number of photons collected at each SiPM row and column position (x i , y i ). Finally, the real position (x0, y0) of the neutron event is obtained through a series of matrix transformation and solution.

[0081] Wherein, Q xi,yi is the intensity information (i.e., photon intensity) related to the number of photons collected by the i-th row and i-th column SiPM; σ x and σ y are the photon distribution broadening in the x and y directions, respectively; and Q b is the background photon intensity and noise. In practice, σ x = σ yAnd the photon distribution is kept fixed value, so that the neutron position (x0, y0) and the standard deviation of the real light intensity A is reduced.

[0082] In the embodiment of the present application, by a series of matrix transformation and matrix processing of the Gaussian distribution expression of the two-dimensional photon intensity, the incident position of the neutron when the neutron event occurs is obtained, including:

[0083] 11) by taking logarithm on both sides of the Gaussian distribution expression of the two-dimensional photon intensity, the first expression is obtained:

[0084] Taking logarithm on both sides of the equation, the first expression is obtained:

[0085]

[0086] Wherein, define:

[0087] Wherein, r represents the conversion parameter.

[0088] 12) matrix transformation is carried out on the first expression to obtain the first matrix expression:

[0089]

[0090] Wherein, define:

[0091]

[0092]

[0093] Wherein, B, alpha, Lambda, e, alpha i , b, represent each conversion parameter.

[0094] 13) matrix processing is carried out on the first matrix expression to obtain the incident position of the neutron:

[0095]

[0096] Wherein, define:

[0097] Wherein, Q represents the conversion matrix parameter.

[0098] The embodiment of the present application obtains the neutron detector with the boron-coated scintillation crystal with the boron film by performing the boron film plating treatment on the surface of the scintillation crystal of the neutron detector; after obtaining the neutron detector with the boron-coated scintillation crystal with the boron film, the pulse waveform data of each channel of the neutron detector is collected according to the trigger signal generated by each event, and the charge ratio of the pulse waveform data of each channel of each event is calculated by using the charge integration method; the charge ratio of the pulse waveform data of each channel of each event is used to determine whether each event is a neutron event or a gamma event; when it is determined that the event is a neutron event, the incident position of the neutron when the neutron event occurs is calculated by using the two-dimensional Gaussian distribution method of the photon response function. The present application provides a method for realizing the positioning of the incident neutron, which can simultaneously achieve the high neutron / gamma discrimination ability, the high detection efficiency and the position resolution, and reduce the cost of the neutron detector. In addition, the present application also provides a scintillator neutron detector with the boron film plated on the surface of the scintillation crystal, which can improve the neutron detection efficiency by using the high energy released by the nuclear reaction between the neutron and the boron, and realize the neutron / gamma discrimination by using the alpha particles generated in the nuclear reaction.

[0099] Figure 2 The present application provides a device for realizing the positioning of the incident neutron, as shown in Figure 2 , which comprises:

[0100] The boron film plating treatment module is configured to obtain the boron-coated scintillation crystal with the boron film by performing the boron film plating treatment on the surface of the scintillation crystal.

[0101] The neutron determination module is configured to collect the pulse waveform data of each channel of the neutron detector according to the trigger signal generated by each event after obtaining the boron-coated scintillation crystal with the boron film, and calculate the charge ratio of the pulse waveform data of each channel of each event by using the charge integration method; the charge ratio of the pulse waveform data of each channel of each event is used to determine whether each event is a neutron event or a gamma event.

[0102] The neutron positioning module is configured to calculate the incident position of the neutron when the neutron event occurs by using the two-dimensional Gaussian distribution method of the photon response function when it is determined that the event is a neutron event.

[0103] The above is a schematic scheme of the device for realizing the positioning of the incident neutron. It should be noted that the technical scheme of the device for realizing the positioning of the incident neutron belongs to the same concept as the technical scheme of the method for realizing the positioning of the incident neutron, and the details of the technical scheme of the device for realizing the positioning of the incident neutron that are not described in detail can be referred to the description of the technical scheme of the method for realizing the positioning of the incident neutron.

[0104] Figure 5is a structural block diagram of a computing device provided by the present application. The components of the computing device 400 include, but are not limited to, a memory 410 and a processor 420. The processor 420 is connected with the memory 410 through a bus 430, and a database 450 is used to save data.

[0105] The computing device 400 also includes an access device 440, which enables the computing device 400 to communicate via one or more networks 460. Examples of these networks include the public switched telephone network (PSTN), a local area network (LAN), a wide area network (WAN), a personal area network (PAN), or a combination of communication networks such as the Internet. The access device 440 can include one or more of any type of network interface (e.g., network interface card (NIC)) such as an IEEE 802.11 wireless local area network (WLAN) wireless interface, a Worldwide Interoperability for Microwave Access (Wi-MAX) interface, an Ethernet interface, a Universal Serial Bus (USB) interface, a cellular network interface, a Bluetooth interface, a near field communication (NFC) interface, and the like, either wired or wireless.

[0106] In one embodiment of the present application, the above-mentioned components of the computing device 400 and other components not shown in the above-mentioned components can be connected with each other, for example, through a bus. It should be understood that, Figure 5 Figure 5 The structural block diagram of the computing device shown is only for the purpose of example, and is not a limitation on the scope of the present application. Other components can be added or replaced as needed by those skilled in the art.

[0107] The computing device 400 can be any type of stationary or mobile computing device, including a mobile computer or mobile computing device (e.g., a tablet computer, a personal digital assistant, a laptop computer, a notebook computer, a netbook, etc.), a mobile phone (e.g., a smartphone), a wearable computing device (e.g., a smart watch, smart glasses, etc.), or other type of mobile device, or a stationary computing device such as a desktop computer or PC. The computing device 400 can also be a mobile or stationary server.

[0108] The processor 420 is configured to execute computer-executable instructions, which, when executed by the processor, implement the steps of the method for positioning incident neutrons by a neutron detector.

[0109] The above is a schematic scheme of a computing device of the present embodiment. It should be noted that the technical scheme of the computing device belongs to the same concept as the technical scheme of the method for positioning incident neutrons by a neutron detector, and the details of the technical scheme of the computing device that are not described in detail can be referred to the description of the technical scheme of the method for positioning incident neutrons by a neutron detector.

[0110] ​The embodiment of the present application further provides a computer readable storage medium, which stores computer executable instructions, and the computer executable instructions realize the steps of the method for realizing incident neutron positioning by the neutron detector when executed by a processor.

[0111] The above is a schematic scheme of the computer readable storage medium of the embodiment. It should be noted that the technical scheme of the storage medium and the technical scheme of the method for realizing incident neutron positioning by the neutron detector belong to the same concept, and the details of the technical scheme of the storage medium which are not described in detail can be referred to the description of the technical scheme of the method for realizing incident neutron positioning by the neutron detector.

[0112] The preferred embodiments of the present application are described above with reference to the accompanying drawings, and the scope of the present application is not limited by this. Any modification, equivalent replacement and improvement made by those skilled in the art without departing from the scope and essence of the present application shall be within the scope of the present application.

Claims

1. A method of a neutron detector implementing localization of incident neutrons, characterized in that, The application relates to a neutron detector with a boron-coated film of a scintillation crystal. The charge ratio of the pulse waveform data of each channel of each event is used to determine whether each event is a neutron event or a gamma event. After obtaining the boron-coated scintillation crystal neutron detector with boron-coated film, the pulse waveform data of each channel of the neutron detector is collected according to the trigger signal generated by each event, and the charge ratio of the pulse waveform data of each channel of each event is calculated, which includes: R=I t2 / (I t1 +I t2 ), R is the charge ratio; I t1 is the charge value obtained by integrating the pulse amplitude with respect to time from the pulse starting point to t1 moment; I t2 is the charge value obtained by integrating the pulse amplitude with respect to time from the pulse t1 moment to the pulse tail. When an event is determined to be a neutron event, a Gaussian distribution expression of two-dimensional photon intensity is constructed according to the photon intensity generated by a nuclear reaction of a neutron at an incident position; and the incident position of the neutron when the nuclear reaction occurs is obtained by a series of matrix transformation and matrix solution of the Gaussian distribution expression of the two-dimensional photon intensity. A first expression is obtained by taking logarithm of both sides of the Gaussian distribution expression of the two-dimensional photon intensity: Wherein, r represents a conversion parameter; wherein the definitions are: A first matrix expression is obtained by matrix transformation of the first expression: The incident position of the neutron is obtained by matrix solution of the first matrix expression: wherein the definitions are: wherein B, a, A, e, a i , b, represent each conversion parameter; Wherein, Q represents a conversion matrix parameter; The Gaussian distribution expression of the two-dimensional photon intensity comprises: The application further relates to a neutron detector with a boron-coated film of a scintillation crystal. where Q xi,yi are the photon intensities collected by the ith row and ith column of silicon photomultiplier (SiPM), respectively; σ x and σ y are the photon distribution broadening in the x and y directions, respectively; Q b is the background photon intensity and noise; x i and y i are the row and column positions of each SiPM pixel, respectively; x0 and y0 are the row and column positions of the neutron true incidence, respectively; and A is the true light emission intensity.

2. The method of claim 1, wherein, The pulse waveform data of each channel of the neutron detector is sampled according to the trigger signal generated by each event, and the charge ratio of the pulse waveform data of each channel of each event is calculated by using the charge integration method. The sum pulse waveform data of each event is calculated according to the pulse waveform data of each channel of the neutron detector sampled according to the trigger signal generated by each event.

3. The method of claim 1, wherein, Two pieces of sum pulse waveform data are obtained by segmenting the sum pulse waveform data of each event, and the charge amount of each piece of sum pulse waveform data is calculated by using the charge integration method. The charge ratio of the pulse waveform data of each channel of each event is obtained according to the charge amount of each piece of sum pulse waveform data. The charge ratio of the pulse waveform data of each channel of each event is used to determine whether each event is a neutron event or a gamma event. The charge ratio distribution of all events is formed by statistical processing of the charge ratio of the pulse waveform data of each channel of each event.

4. The method of claim 3, wherein, The charge ratio threshold value for determining a neutron event and a gamma event is determined according to the charge ratio distribution of all events, and each event is determined to be a neutron event or a gamma event according to the charge ratio threshold value. If the charge ratio of the pulse waveform data of each channel of an event is greater than the charge ratio threshold value, the event is determined to be a neutron event. If the charge ratio of the pulse waveform data of each channel of an event is not greater than the charge ratio threshold value, the event is determined to be a gamma event.

5. The method of claim 4, wherein, The application relates to a neutron detector with a boron-coated film of a scintillation crystal. The application relates to a neutron detector with a boron-coated film of a scintillation crystal. ​ 6. An apparatus for localizing incident neutrons with a neutron detector, the apparatus comprising: ​ ​ The neutron determining module is configured to, after obtaining the neutron detector with the boron-coated scintillation crystal with the boron-coated film, collect pulse waveform data of each channel of the neutron detector according to a trigger signal generated by each event, and calculate a charge ratio of the pulse waveform data of each channel of each event. The charge ratio of the pulse waveform data of each channel of each event is used to determine whether each event is a neutron event or a gamma event. The calculation of the charge ratio of the pulse waveform data of each channel of each event includes: R = I t2 + I t1 + I t2 where R is the charge ratio; I t1 is the charge value obtained by integrating the pulse amplitude with respect to time from the start of the pulse to time t1; and I t2 is the charge value obtained by integrating the pulse amplitude with respect to time from time t1 to the end of the pulse. The neutron positioning module is configured to, when determining that the event is a neutron event, construct a Gaussian distribution expression of two-dimensional photon intensity according to photon intensity generated by a nuclear reaction of the neutron at an incident position, and obtain the incident position of the neutron when the nuclear reaction of the neutron event occurs by performing a series of matrix transformation and matrix solution on the Gaussian distribution expression of the two-dimensional photon intensity. The Gaussian distribution expression of the two-dimensional photon intensity includes: wherein the definitions are:

7. A computing device, comprising: a memory and a processor; wherein the definitions are: wherein B, a, A, e, a i , b, represent each conversion parameter; the memory is configured to store computer executable instructions, and the processor is configured to execute the computer executable instructions, and the computer executable instructions, when executed by the processor, implement the steps of the method for positioning incident neutrons of the neutron detector according to any one of claims 1 to 5.

8. A computer readable storage medium storing computer executable instructions, and the computer executable instructions, when executed by a processor, implement the steps of the method for positioning incident neutrons of the neutron detector according to any one of claims 1 to 5. ​ where Q xi,yi are the photon intensities collected by the ith row and ith column of silicon photomultiplier (SiPM), respectively; σ x and σ y are the photon distribution broadening in the x and y directions, respectively; Q b is the background photon intensity and noise; x i and y i are the row and column positions of each SiPM pixel, respectively; x0 and y0 are the row and column positions of the neutron true incidence, respectively; and A is the true light emission intensity. ​ ​ ​ ​

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