Multilayer scintillator probe based on scintillation fiber, detector and method

Abstract

The invention provides a multi-layer scintillator probe, detector and method based on scintillation fiber, and belongs to the technical field of nuclear detection, the probe comprises a probe main body, the probe main body comprises a first scintillation fiber layer, a second scintillator layer and a third scintillator layer, the second scintillator layer is arranged between the first scintillation optical fiber layer and the third scintillator layer, the first scintillation optical fiber layer is used for discriminating gamma particles and beta particles, the second scintillator layer is used for absorbing the beta particles penetrating through the first scintillation optical fiber layer, and the third scintillator layer is used for measuring the gamma particles. The beta particles and the gamma particles in the beta-gamma mixed field can be identified, and the beta particle energy spectrum and the gamma particle energy spectrum in the beta-gamma mixed field can be accurately measured at the same time.

Description

Technical Field

[0001] The present application belongs to the field of nuclear detection technology, and specifically relates to a multi-layer scintillator probe, a detector and a method based on scintillation optical fiber. Background Art

[0002] In the fields of nuclear industry, nuclear science, medical physics, environmental monitoring and safety inspection, beta rays and gamma rays often coexist. Due to the large difference in their properties, they cause different damage to human tissues. Therefore, accurately distinguishing and measuring the energy spectrum of beta particles and gamma particles in mixed fields is crucial for radiation protection of relevant personnel. Due to the difficulty in distinguishing beta particles and gamma particles in mixed fields, existing related equipment cannot simultaneously measure the beta energy spectrum and gamma energy spectrum in mixed fields, and because the measurements of the two will affect each other, it is difficult to accurately measure the beta particle energy spectrum in the beta-gamma mixed field. Summary of the invention

[0003] Therefore, the technical problem to be solved by the present application is to provide a multi-layer scintillator probe, detector and method based on scintillation optical fiber, which can realize the identification of β particles and γ particles in a β-γ mixed field, and realize the simultaneous and accurate measurement of the β particle energy spectrum and the γ particle energy spectrum in the β-γ mixed field.

[0004] In order to solve the above problems, the first aspect of an embodiment of the present application provides a multi-layer scintillator probe based on scintillating fiber, including a probe body, wherein the probe body includes a first scintillating fiber layer, a second layer of scintillator and a third layer of scintillator, the second layer of scintillator is arranged between the first scintillating fiber layer and the third layer of scintillator, the first scintillating fiber layer is used to distinguish between γ particles and β particles, the second layer of scintillator is used to absorb β particles passing through the first scintillating fiber layer, and the third layer of scintillator is used to measure γ particles.

[0005] Optionally, the first scintillating fiber layer is formed by scintillating fibers arranged in a matrix; the second layer of scintillators is a plastic scintillator; and the third layer of scintillators is a cesium iodide scintillator.

[0006] Optionally, the probe body further includes a polyester film, and the outer surfaces of the second scintillator layer and the third scintillator layer are both wrapped by the polyester film.

[0007] Optionally, the probe also includes a silicon photomultiplier tube, a signal amplifying board and a signal output head. The first scintillating fiber layer, the second layer of scintillator and the third layer of scintillator are arranged one-to-one with the silicon photomultiplier tubes. One of the silicon photomultiplier tubes is connected to the first scintillating fiber layer, and the other two silicon photomultiplier tubes are respectively connected to the corresponding second layer of scintillator and the third layer of scintillator after passing through the polyester film. The signal amplifying board is connected to the silicon photomultiplier tube, and the signal output head is arranged on the surface of the signal amplifying board away from the silicon photomultiplier tube.

[0008] Optionally, the probe further includes a shell, and the probe body, the silicon photomultiplier tube, the signal amplifying board and the signal output head are packaged in the shell.

[0009] Optionally, the shell includes a first end plate, a window is formed on the first end plate, and a polyester film sheet is arranged inside the window to form an exploration window.

[0010] Optionally, the housing further comprises a second end plate, a plurality of connectors are arranged on the second end plate, and the signal output head is correspondingly connected to the connectors via optical fibers.

[0011] A second aspect of the present application provides a detector, comprising any one of the above-mentioned multi-layer scintillator probes based on scintillation optical fiber.

[0012] The third aspect of the present application provides a method for obtaining a β particle energy spectrum and a γ particle energy spectrum, using the detector for measurement, the method for obtaining a β particle energy spectrum and a γ particle energy spectrum comprises:

[0013] respectively collecting the scintillation photons generated by the first scintillation fiber layer, the second scintillator layer and the third scintillator layer, and converting them into electrical signals for output;

[0014] The electrical signal in each layer is divided into two paths, the first path retains the original energy information, and the second path is sent to the logic coincidence unit for identifying beta particles and gamma particles;

[0015] The first electrical signal and the second logic signal processed by the logic coincidence unit are coupled and a detection signal is output, and the output detection signal is classified to identify the beta particle energy spectrum and the gamma particle energy spectrum.

[0016] Optionally, another path is fed into a logic coincidence unit for identifying particle types, including:

[0017] The logic coincidence unit determines the energy deposition of particles in each layer according to the preset threshold;

[0018] When the energy deposition is higher than the preset threshold, a "1" signal is output; when the energy deposition is less than or equal to the preset threshold, a "0" signal is output;

[0019] The logic signals output by the first scintillating fiber layer, the second scintillator layer, and the third scintillator layer are combined to identify the "100" and "110" events as β particles and the "001" event as γ particles.

[0020] By means of the above technical solution, the present invention has at least the following beneficial effects:

[0021] The embodiment of the present application provides a multi-layer scintillator probe, detector and method based on scintillating optical fiber, by sequentially arranging a first scintillating optical fiber layer, a second scintillator layer and a third scintillator layer, wherein the first scintillating optical fiber layer is used to distinguish between γ particles and β particles, the second scintillator layer is used to absorb the β particles passing through the first scintillating optical fiber layer, and the third scintillator layer is used to measure γ particles; it is possible to realize the identification of β particles and γ particles in a β-γ mixed field, and to realize the simultaneous and accurate measurement of the β particle energy spectrum and the γ particle energy spectrum in the β-γ mixed field. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 A schematic diagram of a probe body of a multi-layer scintillator probe based on scintillation optical fiber according to an embodiment of the present application;

[0023] Figure 2 This is an axonometric diagram of a multi-layer scintillator probe based on scintillation optical fiber according to an embodiment of the present application;

[0024] Figure 3 A flow chart of a method for obtaining a beta particle energy spectrum and a gamma particle energy spectrum according to an embodiment of the present application;

[0025] Figure 4 The energy spectrum of the detector of the multi-layer scintillator probe based on the scintillation optical fiber of the embodiment of the present application is actually measured for the Sr-90 source;

[0026] Figure 5 This is a diagram of the energy spectrum actually measured by the detector of the multi-layer scintillator probe based on scintillation optical fiber for a Cs-137 source according to an embodiment of the present application.

[0027] The reference numerals are:

[0028] 1. The first scintillating optical fiber layer; 2. The second scintillator layer; 3. The third scintillator layer; 4. Silicon photomultiplier tube; 5. Signal amplifier board; 6. Signal output head; 7. Polyester film; 8. Shell. DETAILED DESCRIPTION

[0029] In the description of the present application, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise" and the like indicating orientations or positional relationships are based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as limiting the present invention.

[0030] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include one or more of the features. In the description of the present invention, the meaning of "plurality" is two or more, unless otherwise clearly and specifically defined.

[0031] In this application, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like 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 an electrical connection; it can be a direct connection, or it can be an indirect connection through an intermediate medium, or it can be the internal communication of two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0032] The preferred embodiments of the present invention are described below in conjunction with the accompanying drawings. It should be understood that the preferred embodiments described herein are only used to illustrate and explain the present invention, and are not used to limit the present invention.

[0033] See also Figure 1 and Figure 2 As shown, according to an embodiment of the present application, a multi-layer scintillator probe based on scintillating optical fiber is provided, comprising a probe body, the probe body comprising a first scintillating optical fiber layer 1, a second scintillator layer 2 and a third scintillator layer 3, the second scintillator layer 2 is arranged between the first scintillating optical fiber layer 1 and the third scintillator layer 3, the first scintillating optical fiber layer 1 is used to distinguish between γ particles and β particles, the second scintillator layer 2 is used to absorb β particles passing through the first scintillating optical fiber layer 1, and the third scintillator layer 3 is used to measure γ particles.

[0034] By sequentially arranging a first scintillating fiber layer 1, a second scintillator layer 2 and a third scintillator layer 3, wherein the first scintillating fiber layer 1 is used to distinguish between gamma particles and beta particles, the second scintillator layer 2 is used to absorb beta particles passing through the first scintillating fiber layer, and the third scintillator layer 3 is used to measure gamma particles; it is possible to realize the identification of beta particles and gamma particles in a β-γ mixed field, and to realize the simultaneous and accurate measurement of the energy spectrum of beta particles and the energy spectrum of gamma particles in the β-γ mixed field.

[0035] Among them, the second layer of scintillator 2 is arranged between the first layer of scintillator fiber 1 and the third layer of scintillator 3, that is, the second layer of scintillator 2 includes a top surface and a bottom surface, the first layer of scintillator fiber 1 is arranged on the top surface of the second layer of scintillator 2, and the third layer of scintillator 3 is arranged on the bottom surface of the second layer of scintillator 2. This layered structure can effectively filter and distinguish different types of particles, and realize the simultaneous and accurate measurement of the β particle energy spectrum and the γ particle energy spectrum in the β-γ mixed field.

[0036] During specific use, when the particle enters the first scintillating fiber layer 1, the scintillating fiber will emit scintillation light; if the particle still has enough energy after passing through the scintillating light layer 1, it will enter the third layer of scintillator 2, and the second scintillator will also emit scintillation light, which is used to filter out the β particles passing through the first scintillating fiber layer 1. Since the energy of β particles is relatively low, they will usually be completely absorbed by the first scintillating fiber layer 1; if the particle can pass through the first scintillating fiber layer 1 and the second layer of scintillator 2, it will enter the third scintillator layer 3, and the third scintillator will also emit scintillation light. Since the energy of γ particles is relatively high, they can penetrate the first scintillating fiber layer 1 and the third layer of scintillator 2.

[0037] In other embodiments, the first scintillating fiber layer 1 is formed by scintillating fibers arranged in a matrix; the second scintillator layer 2 is a plastic scintillator; and the third scintillator layer 3 is a cesium iodide scintillator.

[0038] The diameter of the scintillating optical fiber is 0.5 mm, and the side length of the first scintillating optical fiber layer 1 is 75 mm. The scintillating optical fibers are closely arranged in a matrix, and can collect photons efficiently.

[0039] The second scintillator layer 2 has a thickness of 18 mm and a side length of 75 mm.

[0040] The third scintillator layer 3 has a thickness of 25.4 mm and a side length of 75 mm.

[0041] The limitation of the thickness of the second scintillator layer 2 and the third scintillator layer 3 can effectively increase the probability of interaction between particles and scintillators, ensuring that most beta particles and low-energy gamma particles are completely absorbed in the scintillators, thereby improving the detection efficiency. The limitation of the side length of the second scintillator layer 2 and the third scintillator layer 3 enables the scintillators to have a larger detection area, enabling the detection of multiple particles at the same time, further improving the detection efficiency.

[0042] In other embodiments, the probe body further includes a polyester film 7, and the outer surfaces of the second layer scintillator 2 and the third layer scintillator 3 are both wrapped by the polyester film 7. The polyester film serves as an optical reflection layer or a light absorption barrier layer to optimize the optical performance of the scintillator. It can reflect the visible light emitted from the back of the scintillator and return it to the inside of the scintillator, thereby improving the photon collection efficiency.

[0043] In other embodiments, the probe further includes a silicon photomultiplier tube 4, a signal amplifier board 5, and a signal output head 6. The first scintillating fiber layer 1, the second scintillator layer 2, and the third scintillator layer 3 are arranged one by one with the silicon photomultiplier tube 4, one of the silicon photomultiplier tubes 4 is connected to the first scintillating fiber layer 1, and the other two silicon photomultiplier tubes 4 are respectively connected to the corresponding second scintillator layer 2 and third scintillator layer 3 after passing through the polyester film 7, the signal amplifier board 5 is connected to the silicon photomultiplier tube 4, and the signal output head 6 is arranged on the surface of the signal amplifier board 5 away from the silicon photomultiplier tube 4. A silicon photomultiplier tube 4 is arranged corresponding to each layer, and the optical signal can be detected and processed independently. This layered detection method can measure the energy deposition of particles in different layers, thereby achieving more accurate particle identification and energy spectrum analysis.

[0044] Among them, the first scintillating fiber layer 1, the second scintillator layer 2 and the third scintillator layer 3 are arranged in one-to-one correspondence with the silicon photomultiplier tubes 4, one of the silicon photomultiplier tubes 4 is connected to the first scintillating fiber layer 1, and the other two silicon photomultiplier tubes 4 are respectively connected to the corresponding second scintillator layer 2 and third scintillator layer 3 after passing through the polyester film 7. That is to say, the probe body is a three-layer structure, and each layer corresponds to a silicon photomultiplier tube 4. Therefore, the number of silicon photomultiplier tubes 4 here is three.

[0045] One of the silicon photomultiplier tubes 4 is connected to the first scintillation optical fiber layer 1 , and the scintillation optical fibers arranged in a matrix are twisted together at the output end and connected to the silicon photomultiplier tube 4 for converting the collected scintillation light into an electrical signal.

[0046] The other two silicon photomultiplier tubes 4 are connected to the corresponding second layer scintillator 2 and third layer scintillator 3 after passing through the polyester film 7, that is, the second layer scintillator 2 and the third layer scintillator 3 are not provided with polyester film 7 at the locations where the silicon photomultiplier tubes 4 are installed, and the silicon photomultiplier tubes 4 connected to the second layer scintillator 2 collect the scintillation photons passing through the first scintillation fiber layer 1 and convert them into electrical signals. The silicon photomultiplier tubes 4 connected to the third layer scintillator 3 collect the scintillation photons passing through the first scintillation fiber layer 1 and the second scintillator layer 2 and convert them into electrical signals.

[0047] In other embodiments, the probe further includes a housing 8, and the probe body, the silicon photomultiplier tube 4, the signal amplifying board 5, and the signal output head 6 are encapsulated in the housing 8. The arrangement of the housing 8 is used to protect the probe body, the silicon photomultiplier tube 4, the signal amplifying board 5, and the signal output head 6, thereby extending the service life of each component.

[0048] Among them, Figure 2 As shown, the shell 8 is a stepped cylindrical structure, including a large diameter part and a small diameter part. The probe body, silicon photomultiplier tube 4, signal amplifier board 5 and signal output head 6 are installed in the space formed by the large diameter part. The large diameter part is connected to the small diameter part and arranged coaxially. The small diameter part can be used as a handheld part.

[0049] Specifically, the housing 8 is made of aluminum.

[0050] In other embodiments, the housing 8 includes a first end plate, a window is formed on the first end plate, and a polyester film is provided inside the window to form a probe window. The probe window is a key part for the probe to receive radiation, which allows specific radiation to enter the sensitive area inside the probe, so as to be detected by the probe. A polyester film is provided inside the probe window, which can protect the sensitive components inside the probe from damage by the external environment (such as moisture, dust, etc.) without affecting the penetration of radiation.

[0051] The shell 8 includes a first end plate, on which a window is provided, that is, the large diameter portion of the shell 8 includes the first end plate, which is the end plate facing away from the small diameter portion.

[0052] The probe body is arranged in the large diameter part, wherein the first scintillation optical fiber layer 1 of the probe body is arranged facing the probe window.

[0053] Specifically, the thickness of the polyester film sheet is 2 um.

[0054] In other embodiments, the housing 8 further includes a second end plate, on which a plurality of connectors are disposed, and the signal output head 6 is connected to the connectors correspondingly via optical fibers.

[0055] The shell 8 further includes a second end plate, that is, the small diameter portion of the shell 8 includes the second end plate, and the second end plate is the end plate facing away from the large diameter portion.

[0056] In a second aspect of the embodiment of the present application, a detector is provided, including any of the above-mentioned multilayer scintillator probes based on scintillation optical fibers. By using the detector of the probe of the present application, it is possible to identify beta particles and gamma particles in a beta-gamma mixed field, and to simultaneously and accurately measure the energy spectrum of beta particles and the energy spectrum of gamma particles in a beta-gamma mixed field.

[0057] When used specifically: When a particle passes through the window and enters the first scintillating fiber layer, the scintillating fiber will emit scintillation light, and the output ends of the scintillating fibers are twisted together and connected to the silicon photomultiplier tube 4 to convert the scintillation photons into electrical signals. If the particle still has enough energy after passing through the first scintillating fiber layer, it will enter the second layer of scintillator, and these scintillation photons will be collected and converted into electrical signals by the silicon photomultiplier tube 4 connected to the second layer of scintillator 2. If the particle can pass through the first scintillating fiber layer 1 and the second scintillator layer 2, it will enter the third scintillator layer 3, and these scintillation photons will be collected and converted into electrical signals by the silicon photomultiplier tube 4 connected to the third layer of scintillator 3. This layered detection method can measure the energy deposition of particles in different layers, thereby achieving more accurate particle identification and energy spectrum analysis.

[0058] like Figure 3 As shown, the third aspect of the embodiment of the present application provides a method for obtaining a beta particle energy spectrum and a gamma particle energy spectrum, and the method for obtaining a beta particle energy spectrum and a gamma particle energy spectrum by measuring with a detector includes the following steps:

[0059] Step S1 , respectively collecting scintillation photons generated by the first scintillating fiber layer 1 , the second scintillator layer 2 , and the third scintillator layer 3 , and converting them into electrical signals for output.

[0060] After the particles enter through the exploration window, the first scintillating fiber layer 1 efficiently collects scintillation photons through the silicon photomultiplier tube 4 connected thereto, and converts them into electrical signals for output; the second layer of scintillator 2 is used to collect scintillation photons passing through the first scintillating fiber layer 1, and converts them into electrical signals for output; the third layer of scintillator 3 is used to collect scintillation photons passing through the first scintillating fiber layer 1 and the second layer of scintillator 2, and converts them into electrical signals for output.

[0061] Step S2, the electrical signal in each layer is divided into two paths, the first path retains the original energy information, and the second path is sent to the logic coincidence unit for identifying β particles and γ particles.

[0062] The electrical signal in each layer is divided into two paths. The first path retains the original energy information for subsequent analysis of the particle energy spectrum. The second path is sent to the logic coincidence unit for calculation, that is, transmitted to the integrated circuit chip for particle type identification, that is, for identifying beta particles and gamma particles.

[0063] Step S3, coupling the first electrical signal and the second logic signal processed by the logic coincidence unit and outputting a detection signal, and classifying the output detection signal for identifying the β particle energy spectrum and the γ particle energy spectrum.

[0064] The first electrical signal and the second logical signal processed by the logic coincidence unit are coupled and a detection signal is output, that is, after the first electrical signal of the first scintillation optical fiber layer 1, the second scintillator layer 2 and the third scintillator layer 3 and the second logical signal of the first scintillation optical fiber layer 1, the second scintillator layer 2 and the third scintillator layer 3 are coupled, the detection signal is output.

[0065] The output detection signal is classified to identify the β particle energy spectrum and the γ particle energy spectrum. That is to say, the second logic signal processed by the logic coincidence unit is used as the judgment standard to classify the detection signal, identify the β particles and the γ particles, and then form the β particle energy spectrum and the γ particle energy spectrum.

[0066] As a refinement and extension of the specific implementation of the above embodiment, in order to fully illustrate the specific implementation process of this embodiment, another method for obtaining the energy spectrum of β particles and the energy spectrum of γ particles is provided, and the method includes:

[0067] Step S1 , respectively collecting scintillation photons generated by the first scintillating fiber layer 1 , the second scintillator layer 2 , and the third scintillator layer 3 , and converting them into electrical signals for output.

[0068] After the particles enter through the exploration window, the first scintillating fiber layer 1 efficiently collects scintillation photons through the silicon photomultiplier tube 4 connected thereto, and converts them into electrical signals for output; the second layer of scintillator 2 is used to collect scintillation photons passing through the first scintillating fiber layer 1, and converts them into electrical signals for output; the third layer of scintillator 3 is used to collect scintillation photons passing through the first scintillating fiber layer 1 and the second layer of scintillator 2, and converts them into electrical signals for output.

[0069] Step S2, the electrical signal in each layer is divided into two paths, the first path retains the original energy information, and the second path is sent to the logic coincidence unit for identifying β particles and γ particles.

[0070] The electrical signal in each layer is divided into two paths. The first path retains the original energy information for subsequent analysis of the particle energy spectrum. The second path is sent to the logic coincidence unit for calculation, that is, transmitted to the integrated circuit chip for particle type identification, that is, for identifying beta particles and gamma particles.

[0071] In step S21, the logic coincidence unit determines the energy deposition of particles in each layer according to a preset threshold value; the preset threshold value in the method of the present application is 40 KeV.

[0072] When the energy deposition is higher than the preset threshold, a "1" signal is output; when the energy deposition is less than or equal to the preset threshold, a "0" signal is output.

[0073] Step S22, combining the logic signals output by the first scintillating fiber layer 1, the second scintillator layer 2 and the third scintillator layer 3, identifying the "100" and "110" events as β particles, and identifying the "001" event as γ particles.

[0074] Step S3, coupling the first electrical signal and the second logic signal processed by the logic coincidence unit and outputting a detection signal, and classifying the output detection signal for identifying the β particle energy spectrum and the γ particle energy spectrum.

[0075] The first electrical signal and the second logical signal processed by the logic coincidence unit are coupled and a detection signal is output, that is, after the first electrical signal of the first scintillation optical fiber layer 1, the second scintillator layer 2 and the third scintillator layer 3 and the second logical signal of the first scintillation optical fiber layer 1, the second scintillator layer 2 and the third scintillator layer 3 are coupled, the detection signal is output.

[0076] The output detection signal is classified to identify the β particle energy spectrum and the γ particle energy spectrum. That is to say, the second logic signal processed by the logic coincidence unit is used as the judgment standard to classify the detection signal, identify the β particles and the γ particles, and then form the β particle energy spectrum and the γ particle energy spectrum.

[0077] Example 1

[0078] Figure 4 This is the measured energy spectrum of the probe of this application for the Sr-90 source. The counts of β particles and γ particles measured by the probe can be obtained respectively by full spectrum integration, wherein the net count of β channel is: 125.88×1357=170819.16; the net count of γ channel is: 0.556×1357=754.5; when the measured source is a β radiation source, β misidentification rate=γ channel count÷(β channel count+γ channel count); it can be obtained that β misidentification rate=754.5÷(754.5+170819.16)≈0.44%.

[0079] Example 2

[0080] Figure 5 This is the measured energy spectrum of the probe of this application for the Cs-137 source. Similarly, the counts of β particles and γ particles measured by the probe can be obtained respectively through full spectrum integration, wherein the net count of β channel is: 1.224×1331=1629.144; the net count of γ channel is: 99.43×1331=132341.33; when the measured source is a γ radiation source, the γ misidentification rate=β channel count / (β channel count+γ channel count); it can be obtained that the γ misidentification rate=1629.144÷(1629.144+132341.33)≈1.22%.

[0081] In summary, the use of this probe can achieve accurate identification of β particles and γ particles in the energy range of 0.05MeV-3.6MeV in the β-γ mixed field, with the misidentification rate of β particles less than 0.5%, and the misidentification rate of γ particles less than 1.5%, and the β particle energy spectrum and γ particle energy spectrum can be output simultaneously through one measurement.

[0082] It is easy for those skilled in the art to understand that, under the premise of no conflict, the above-mentioned advantageous methods can be freely combined and superimposed.

[0083] The above are only preferred embodiments of the present application and are not intended to limit the present application. Any modifications, equivalent replacements and improvements made within the spirit and principles of the present application shall be included in the protection scope of the present application. The above are only preferred implementations of the present application. It should be pointed out that for ordinary technicians in this technical field, several improvements and variations can be made without departing from the technical principles of the present application, and these improvements and variations should also be regarded as the protection scope of the present application.

Claims

1. A multi-layer scintillator probe based on scintillation optical fiber, characterized in that: The probe body comprises a first scintillating fiber layer (1), a second scintillator layer (2) and a third scintillator layer (3), wherein the second scintillator layer (2) is arranged between the first scintillating fiber layer (1) and the third scintillator layer (3), the first scintillating fiber layer (1) is used to distinguish between gamma particles and beta particles, the second scintillator layer (2) is used to absorb beta particles passing through the first scintillating fiber layer (1), and the third scintillator layer (3) is used to measure gamma particles.

2. A multi-layer scintillator probe based on scintillation optical fiber according to claim 1, characterized in that: The first scintillating optical fiber layer (1) is formed by scintillating optical fibers arranged in a matrix; the second layer of scintillators (2) is a plastic scintillator; and the third layer of scintillators (3) is a cesium iodide scintillator.

3. A multi-layer scintillator probe based on scintillation optical fiber according to any one of claims 1 or 2, characterized in that: The probe body further comprises a polyester film (7), and the outer surfaces of the second layer scintillator (2) and the third layer scintillator (3) are both wrapped by the polyester film (7).

4. A multi-layer scintillator probe based on scintillation optical fiber according to claim 3, characterized in that: The probe further comprises a silicon photomultiplier tube (4), a signal amplifying board (5) and a signal output head (6); the first scintillating optical fiber layer (1), the second scintillator layer (2) and the third scintillator layer (3) are arranged in one-to-one correspondence with the silicon photomultiplier tube (4); one of the silicon photomultiplier tubes (4) is connected to the first scintillating optical fiber layer (1); the other two silicon photomultiplier tubes (4) are respectively connected to the corresponding second scintillator layer (2) and the third scintillator layer (3) after passing through the polyester film (7); the signal amplifying board (5) is connected to the silicon photomultiplier tube (4); and the signal output head (6) is arranged on a surface of the signal amplifying board (5) that is away from the silicon photomultiplier tube (4).

5. A multi-layer scintillator probe based on scintillation optical fiber according to claim 4, characterized in that: The probe further comprises a shell (8), and the probe body, the silicon photomultiplier tube (4), the signal amplifying board (5) and the signal output head (6) are packaged in the shell (8).

6. A multi-layer scintillator probe based on scintillation optical fiber according to claim 5, characterized in that: The shell (8) comprises a first end plate, a window is formed on the first end plate, and a polyester film sheet is arranged inside the window to form an exploration window.

7. The multi-layer scintillator probe based on scintillation optical fiber according to claim 5, characterized in that: The housing (8) further comprises a second end plate, on which a plurality of connectors are arranged, and the signal output head (6) is correspondingly connected to the connectors via optical fibers.

8. A detector, characterized in that: A multi-layer scintillator probe based on scintillation optical fiber comprising any one of claims 1 to 7.

9. A method for obtaining a beta particle energy spectrum and a gamma particle energy spectrum, characterized in that: The detector of claim 8 is used for measurement, and the method for obtaining the energy spectrum of beta particles and the energy spectrum of gamma particles comprises: respectively collecting scintillation photons generated by the first scintillation optical fiber layer (1), the second scintillator layer (2) and the third scintillator layer (3), and converting them into electrical signals for output; The electrical signal in each layer is divided into two paths, the first path retains the original energy information, and the second path is sent to the logic coincidence unit for identifying beta particles and gamma particles; The first electrical signal and the second logic signal processed by the logic coincidence unit are coupled and a detection signal is output, and the output detection signal is classified to identify the beta particle energy spectrum and the gamma particle energy spectrum.

10. The method for obtaining a beta particle energy spectrum and a gamma particle energy spectrum according to claim 9, characterized in that: The other path is sent to the logic coincidence unit to identify the particle type, including: The logic coincidence unit determines the energy deposition of particles in each layer according to the preset threshold; When the energy deposition is higher than the preset threshold, a "1" signal is output; when the energy deposition is less than or equal to the preset threshold, a "0" signal is output; The logic signals output by the first scintillating fiber layer (1), the second scintillator layer (2) and the third scintillator layer (3) are combined to identify the "100" and "110" events as beta particles and the "001" event as gamma particles.

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