A well drilling type muon detector and muon imaging method

Abstract

The application discloses a kind of drilling type muon detector and muon imaging method, including cylindrical shell, first scintillator matrix and second scintillator matrix;First scintillator matrix includes two first scintillator sub-matrix enclosed into tubular shape matched with inner wall shape, and first scintillator sub-matrix is formed by the parallel arrangement of multiple scintillator strips extending in the axial direction of shell;Second scintillator matrix is arranged in the inner side of first scintillator matrix, and includes four second scintillator sub-matrix enclosed into tubular shape matched with the shape of the inner side of first scintillator matrix, and second scintillator sub-matrix includes multiple arc-shaped scintillators arranged in parallel in the axial direction of shell.Compared with prior art, the application directly obtains the muon trigger position in the axial direction by arranging scintillators in the axial direction of detector, which greatly improves the accuracy of imaging results.The application further improves the accuracy of imaging results by introducing charge barycenter method to correct the coordinates of muon hitting scintillator.

Description

Technical Field

[0001] This invention relates to the field of muon imaging technology, specifically to a drilling-type muon detector and a muon imaging method. Background Technology

[0002] Research on the application of muon transmission imaging technology in mineral exploration can be traced back to 1979, when L. Malmqvist conducted an experimental study on the feasibility of applying muon transmission imaging technology to mineral exploration. The results showed that muon transmission imaging technology could reflect the density changes of the detected rock mass. For the next thirty years, due to limitations in detector technology, research progress in this technology in mineral exploration was slow. However, with the development of detector technology, a series of important research results have been achieved. For example, in 2014, Douglas Bryman placed multiple muon detectors in a 490m tunnel below the ore body to image the ore body, successfully detecting lead-zinc ore. This was the first successful blind detection using muon transmission imaging technology in the field of mineral exploration. Then, in 2018, Doug Schouten placed detectors at different locations in the MacArthur River uranium mine to image uranium ore, pushing the imaging method from two-dimensional to three-dimensional.

[0003] Chinese invention patent CN115247557A discloses a calorimeter-type wellbore muon detector. This detector consists of a scintillator matrix composed of multiple scintillator bars. It determines the muon incident angle on a plane perpendicular to the axis by calculating the amplitude of the triggered scintillator bar and its light signal. The difference in light signal amplitude at both ends determines the axial muon triggering position and its angle with the axis, thus determining the muon's incident path and achieving muon imaging. Its drawback is that this device relies solely on the photon transmission mechanism within the plastic scintillator bars to calculate the axial muon triggering position, resulting in a significant deviation between the calculated and actual triggering positions, leading to inaccurate imaging results. Summary of the Invention

[0004] This application provides a drilling-type muon detector and a muon imaging method. By setting a scintillator along the detector's axis, the axial muon trigger position can be directly obtained. This solves the problem that existing muon detectors rely solely on the photon transmission mechanism in plastic scintillators to calculate the axial muon trigger position, resulting in a large deviation between the calculated and actual muon trigger position and inaccurate imaging results.

[0005] To achieve the above objectives, this application adopts the following technical solution.

[0006] On the one hand, a drilling-type muon detector is provided, comprising a cylindrical shell, a first scintillator matrix, and a second scintillator matrix;

[0007] The first scintillator matrix is ​​disposed on the inner wall of the outer shell and includes two first scintillator sub-matrices with a semi-circular cross-section. The two first scintillator sub-matrices form a tube that matches the shape of the inner wall. The first scintillator sub-matrices are composed of multiple scintillator strips extending along the axial direction of the outer shell arranged in parallel. Each scintillator strip is coupled to a first signal readout device at its end.

[0008] The second scintillator matrix is ​​located inside the first scintillator matrix and includes four second scintillator sub-matrices extending along the axial direction of the outer shell. The four scintillator sub-matrices form a tubular shape that matches the inner shape of the first scintillator matrix. The scintillator sub-matrices include a plurality of arc-shaped scintillators arranged side by side along the axial direction of the outer shell. Each arc-shaped scintillator has a second signal readout device coupled to its end.

[0009] In some embodiments, a cavity is provided inside the second scintillator matrix, and a signal processing circuit board is provided inside the cavity. The signal processing circuit board is electrically connected to the first signal readout device and the second signal readout device, respectively.

[0010] In some embodiments, the first signal readout device is coupled to both ends of the scintillator strip.

[0011] In some embodiments, a gap is provided between two adjacent scintillator sub-matrices and two other adjacent scintillator sub-matrices among the four scintillator sub-matrices, and the second signal readout device is located within the gap.

[0012] On another front, a muon imaging method is provided, which uses the aforementioned drilling-type muon detector for muon imaging, including:

[0013] The positions of the scintillator strips and arc scintillators struck by the muon during its incident and exit phases are determined based on the magnitude of the signal amplitude generated when the muon hits the detector.

[0014] The incident coordinates (x, y, z) and exit coordinates (Ox, Oy, Oz) of the muon are determined based on the positions of the scintillator strips and arc scintillators it hits during its incident and exit phases. Here, x, y, Ox, and Oy are determined based on signals acquired by the first signal readout device, and z and Oz are determined based on signals acquired by the second signal readout device. The origin is the midpoint of the detector's centerline; the x-axis direction is upward from the top-view perspective; the y-axis direction is to the left from the top-view perspective; and the z-axis direction is upward from the front-view perspective.

[0015] Based on the incident coordinates (x, y, z) and exit coordinates (Ox, Oy, Oz) of the muon, calculate the vector Dx = Ox - x in the x-axis direction, the vector Dy = Oy - y in the y-axis direction, and the vector Dz = Oz - z in the z-axis direction.

[0016] The azimuth angle of the munia can be calculated using the following formula. And zenith angle θ:

[0017]

[0018]

[0019] According to the azimuth angle of Muzi The muon imaging image is obtained by combining the zenith angle θ.

[0020] In some embodiments, the positions of the scintillator strips and arc scintillators struck by the muon during incident and exit are determined based on the magnitude of the signal amplitude generated when the muon strikes the detector:

[0021] When a muon hits the same first scintillator submatrix during both incident and exit, the scintillator strip corresponding to the largest signal amplitude is taken as the scintillator strip hit during the incident phase of the muon, and the scintillator strip corresponding to the second largest signal amplitude is taken as the scintillator strip hit during the exit phase of the muon.

[0022] When the muon strikes different first scintillator sub-matrices during its incident and exit phases, the two scintillator bars with the largest signal amplitude in the two first scintillator sub-matrices are respectively taken as the two scintillator bars struck by the muon.

[0023] The two arc scintillators with the largest signal amplitude in the four scintillator sub-matrices are taken as the two arc scintillators hit by the muon. The arc scintillator with the larger z-coordinate value is taken as the arc scintillator hit when the muon is incident, and the arc scintillator with the smaller z-coordinate value is taken as the arc scintillator hit when the muon is exiting.

[0024] In some embodiments, the scintillator strips and arc scintillators are pre-numbered sequentially, and the positions of the scintillator strips and arc scintillators struck during muon incident and ejection are determined according to the number.

[0025] In some embodiments, when determining the incident coordinates (x, y, z) and exit coordinates (Ox, Oy, Oz) of the muon based on the positions of the scintillator strips and arc scintillators struck during incident and exit,

[0026] x and y are determined by the angle between the scintillator strip hit by the muon incident and the x-axis or y-axis, and by R; z is determined by the z-coordinate value of the arc scintillator hit by the muon incident.

[0027] Ox and Oy are determined based on the angle between the scintillator strip struck by the muon and the x-axis or y-axis, and R. z is determined based on the z-coordinate value of the arc-shaped scintillator struck by the muon. R is the distance between the geometric center of the scintillator strip and the detector centerline.

[0028] In some embodiments, determining the incident coordinates (x, y, z) and exit coordinates (Ox, Oy, Oz) of the muon based on the positions of the scintillator strips and arc scintillators struck during incident and exit includes calculating the incident coordinates (x, y, z) and exit coordinates (Ox, Oy, Oz) of the muon using the following formula:

[0029] When 0 <i<i 总 At -1,

[0030] When i = 0

[0031] when i=i 总 At -1,

[0032] When 0 <j<j 总 At -1,

[0033] When j = 0

[0034] When j = j 总 At -1,

[0035] When 0 z z总 At -1,

[0036] when i z When = 0,

[0037] when i z =i z总 At -1,

[0038] When 0 <j z <j z总 At -1,

[0039] When j z When = 0,

[0040] When j z =j z总 At -1,

[0041] ​​Where R is the distance between the geometric center of the scintillator bar and the centerline of the detector. Let Δω be the angle between the geometric center of the scintillator strip with index 0 and the x-axis, Δω be the difference in angle between two adjacent scintillator strips, Z0 be the z-coordinate of the geometric center of the arc scintillator with index 0, ΔZ be the difference in z-coordinate between two adjacent arc scintillators, and i be the index of the scintillator strip hit by the muon incident. 总 Let i be the total number of scintillator bars in the first scintillator submatrix, i = 0, 1, 2, 3, ..., i 总 -1; j is the index of the scintillator bar hit by the muon during its incident motion, j 总 The total number of scintillator bars in the first scintillator submatrix, j = 0, 1, 2, 3, ..., j 总 -1; i 总 =j 总 i z The number of the arc scintillator hit by the muon during its incident motion, i z总 i represents the total number of arc-shaped scintillators in the second scintillator submatrix. z =0, 1, 2, 3, ..., i z总 -1; j z j is the serial number of the arc scintillator that the muon hit when it was launched. z总 j represents the total number of arc-shaped scintillators in the second scintillator submatrix. z =0, 1, 2, 3, ..., j z总 -1; i z总 =j z总 E i The signal amplitude generated by the first signal readout device corresponding to the scintillator bar with serial number i. E is the sum of the signal amplitudes generated by the first signal readout device corresponding to the scintillator bar with sequence number i and the scintillator bar adjacent to it. j The signal amplitude generated by the first signal readout device corresponding to the scintillator bar with sequence number j. The sum of the signal amplitudes generated by the first signal readout device corresponding to the scintillator bar with sequence number j and the scintillator bar adjacent to it with sequence number j. For the sequence number i z The signal amplitude generated by the second signal readout device corresponding to the arc-shaped scintillator. For the sequence number i z The arc-shaped scintillator and the one with the serial number i z The sum of the signal amplitudes generated by the second signal readout devices corresponding to the adjacent arc scintillators. For the sequence number j z The signal amplitude generated by the second signal readout device corresponding to the arc-shaped scintillator. For the sequence number jz The arc-shaped scintillator and the one with the serial number j z The sum of the signal amplitudes generated by the second signal readout device corresponding to the adjacent arc scintillators.

[0042] In some embodiments, if the sum of the signal amplitudes obtained by each of the first signal readout devices in the two first scintillator sub-matrices is not zero, then the muon strikes different first scintillator sub-matrices during incident and exit; otherwise, the muon strikes the same first scintillator sub-matrices during incident and exit.

[0043] This application has at least the following technical effects or advantages:

[0044] 1. By setting a scintillator along the detector's axis to directly obtain the muon trigger position along the axis, the accuracy of the imaging results is greatly improved.

[0045] 2. By introducing the charge centroid method to correct the coordinates of the muon hitting the scintillator, the accuracy of the imaging results is further improved. Attached Figure Description

[0046] Figure 1 This is a schematic diagram of the structure of a drilling-type muon detector in one embodiment of this application;

[0047] Figure 2 This is a schematic diagram of the right semi-cylinder of a drilling-type muon detector in one embodiment of this application;

[0048] Figure 3 This is a schematic diagram of the structure of the first scintillator matrix and the second scintillator matrix in one embodiment of this application;

[0049] Figure 4 This is a cross-sectional view of a drilling-type muon detector in one embodiment of this application (the housing and signal processing circuit board are hidden).

[0050] Figure 5 This is a schematic diagram showing the sequence number of the scintillator bars and their x and y axes in one embodiment of this application;

[0051] Figure 6 This is a schematic diagram showing the serial number of the arc-shaped scintillator and its z-axis in one embodiment of this application;

[0052] Figure 7 This is a schematic diagram showing the state of different first scintillator sub-matrices when the muon is incident and emitted, respectively, in one embodiment of this application;

[0053] Figure 8 This is a schematic diagram of the state when a muon is incident and emitted and hits the same first scintillator submatrix in one embodiment of this application;

[0054] Figure 9This is a schematic diagram showing the state of different second scintillator sub-matrices when the muon is incident and emitted, respectively, in one embodiment of this application;

[0055] Figure 10 For an embodiment of this application, regarding parameters R, A diagram illustrating the meaning of Δω;

[0056] Figure 11 This is a schematic diagram of the state when a muon is incident and emitted and hits the upper edge of the first scintillator submatrix in one embodiment of this application;

[0057] Figure 12 This is a schematic diagram illustrating the state of the muon hitting the lower edge of the second scintillator submatrix during incident and exit phases in one embodiment of this application. Detailed Implementation

[0058] To better understand the above technical solutions, the following will provide a detailed explanation of the technical solutions in conjunction with the accompanying drawings and specific implementation methods.

[0059] Example 1

[0060] See Figures 1-4 A drilling-type muon detector includes a cylindrical outer shell 1, a first scintillator matrix, and a second scintillator matrix;

[0061] The first scintillator matrix is ​​disposed on the inner wall of the outer casing 1, and includes two first scintillator sub-matrices with semi-circular cross-sections (including the left first scintillator sub-matrix 211 and the left first scintillator sub-matrix 212). The two first scintillator sub-matrices form a tubular shape that matches the shape of the inner wall. The first scintillator sub-matrix is ​​formed by multiple scintillator strips 22 extending along the axial direction of the outer casing arranged in parallel. Each scintillator strip 22 has a first signal readout device 23 coupled to its end. Preferably, both ends of the scintillator strip 22 are coupled to the first signal readout device 23.

[0062] The second scintillator matrix is ​​located inside the first scintillator matrix and includes four second scintillator sub-matrices extending along the axial direction of the outer shell (including a second scintillator sub-matrix 311 on the upper left, a second scintillator sub-matrix 312 on the lower left, a second scintillator sub-matrix 313 on the upper right, and a second scintillator sub-matrix 314 on the lower right). The four scintillator sub-matrices form a tubular shape that matches the inner shape of the first scintillator matrix. Each scintillator sub-matrix 31 includes multiple arc-shaped scintillators 32 arranged side by side along the axial direction of the outer shell. A second signal readout device 33 is coupled to the end of each arc-shaped scintillator. Preferably, a gap is provided between two adjacent scintillator sub-matrices and two other adjacent scintillator sub-matrices in the four scintillator sub-matrices 31, and the second signal readout device 33 is located within the gap.

[0063] The inner side of the second scintillator matrix is ​​provided with a cavity, and a signal processing circuit board 4 is provided in the cavity. The signal processing circuit board 4 is electrically connected to the first signal reading device 23 and the second signal reading device 33 respectively.

[0064] In this embodiment, the first signal readout device 23 and the second signal readout device 33 can be SiPMs. The SiPMs respond to the signals generated by muons hitting the scintillator bars and arc scintillators, and the signal processing circuit board 4 stores the signal amplitude information of each SiPM as a text file. The text file is stored in an SD card coupled to the signal processing circuit board 4 for subsequent analysis using algorithms. After the detector is removed from underground, the data in the SD card is extracted, and the zenith angle and azimuth angle information of each incident muon are calculated using algorithms to create a muon imaging map.

[0065] Example 2

[0066] Since the drilling-type muon detector of this application is buried underground, this embodiment assumes that the muon incident direction is from top to bottom. When extracting data from the SD card, the SiPM amplitude information generated by each muon incident on the scintillator bar and the arc scintillator is extracted, and then the zenith angle and azimuth angle information of each incident muon are calculated using the following algorithm. Each scintillator bar and arc scintillator has a corresponding serial number, which is used later to determine the geometric position. This embodiment also defines the following coordinate system: the origin is the midpoint of the detector centerline, the x-axis direction is upward from the top view, the y-axis direction is to the left from the top view, and the z-axis direction is upward from the front view. Figure 5 and Figure 6 As shown.

[0067] A muon imaging method, which uses the aforementioned drilling-type muon detector for muon imaging, includes:

[0068] S1. Determine the positions of the scintillator strips and arc scintillators struck by the muon during its incident and exit phases based on the magnitude of the signal amplitude generated when the muon hits the detector. Specifically, this includes:

[0069] When the muon is incident and emitted, it hits the same first scintillator submatrix (e.g. Figure 8 When the signal amplitude is the largest, the scintillator bar corresponding to the largest signal amplitude is taken as the scintillator bar hit when the muon is incident, and the scintillator bar corresponding to the second largest signal amplitude is taken as the scintillator bar hit when the muon is exiting.

[0070] When the muon is incident and emitted, it hits different first scintillator sub-matrices (such as...). Figure 7 As shown), the two scintillator bars with the largest signal amplitude in the two first scintillator submatrices are respectively taken as the two scintillator bars hit by the muon.

[0071] Furthermore, since the probability of a muon hitting the detector at a perpendicular incidence is almost zero, we only consider cases where the muon hits different second scintillator sub-matrices (such as...) during incidence and exit. Figure 9 In the case shown): the two arc-shaped scintillators with the largest signal amplitude among the four scintillator sub-matrices are taken as the two arc-shaped scintillators hit by the muon. The arc-shaped scintillator with the larger z-coordinate value is taken as the arc-shaped scintillator hit when the muon is incident, and the arc-shaped scintillator with the smaller z-coordinate value is taken as the arc-shaped scintillator hit when the muon is exiting. After determining the arc-shaped scintillator hit when the muon is incident, the scintillator strip located in the same semicircle as that arc-shaped scintillator is taken as the scintillator strip hit when the muon is incident.

[0072] The logic for determining whether a muon hits the same first scintillator submatrix during incident and exit is as follows: if the sum of the signal amplitudes obtained by the first signal readout devices in both first scintillator submatrixes is not zero, then the muon hits different first scintillator submatrixes during incident and exit; otherwise, the muon hits the same first scintillator submatrix during incident and exit.

[0073] S2. Determine the incident coordinates (x, y, z) and exit coordinates (Ox, Oy, Oz) of the muon based on the positions of the scintillator strip and the arc scintillator it strikes during incident and exit. Specifically, x, y, Ox, and Oy are determined based on signals acquired by the first signal readout device, and z and Oz are determined based on signals acquired by the second signal readout device. Specifically, x and y are determined based on the angle between the scintillator strip struck by the muon during incident and the x-axis or y-axis, and R; z is determined based on the z-coordinate value of the arc scintillator struck by the muon during incident; Ox and Oy are determined based on the angle between the scintillator strip struck by the muon during exit and the x-axis or y-axis, and R; z is determined based on the z-coordinate value of the arc scintillator struck by the muon during exit. R is the distance between the geometric center of the scintillator strip and the detector centerline.

[0074]

[0075]

[0076]

[0077]

[0078] z=-Z0+(ΔZ·i z );

[0079] Oz=-Z0+(ΔZ·j z );

[0080] Among them, such as Figure 10As shown, R is the distance between the geometric center of the scintillator bar and the centerline of the detector. Let Δω be the angle between the geometric center of the scintillator strip with index 0 and the x-axis, Δω be the difference in angle between two adjacent scintillator strips, Z0 be the z-coordinate of the geometric center of the arc scintillator with index 0, ΔZ be the difference in z-coordinate between two adjacent arc scintillators, i be the index of the scintillator strip hit by the muon incident, j be the index of the scintillator strip hit by the muon incident, i z

[0081] j is the serial number of the arc scintillator hit by the muon during its incident trajectory. z This is the serial number of the arc-shaped scintillator that the muon hit when it was launched.

[0082] It should be noted that since the x, y, and z axes all have directions, the calculation formulas should be adjusted according to the actual positive and negative values ​​of the coordinates. Due to the complexity of the situation, to avoid redundancy, this embodiment does not discuss the formulas for each case individually. Those skilled in the art can derive the specific formulas for each case from the above formulas based on basic mathematical knowledge. In addition, different numbering methods will also affect the specific formulas, and formulas derived from the above formulas are also within the scope of protection of this invention.

[0083] S3. Calculate the vectors Dx = Ox - x, Dy = Oy - y, and Dz = Oz - z of the muon based on its incident coordinates (x, y, z) and exit coordinates (Ox, Oy, Oz).

[0084] S4. Calculate the azimuth angle of the muon using the following formula. And zenith angle θ:

[0085]

[0086]

[0087] S5. Based on the azimuth angle of the muon The muon imaging image is obtained by combining the zenith angle θ.

[0088] Obtain the azimuth angles of each muon After obtaining the zenith angle θ, existing muon imaging methods can be used to obtain muon imaging images. For example, a flux map can be plotted, and the obtained muon flux information can be compared with the muon flux information under natural sky conditions to obtain the flux ratio of incident muons at each zenith angle and azimuth angle, thus plotting the imaging map. Reference: G. Bonomi, Applications of cosmic-ray muons, 2020.

[0089] Example 3

[0090] Since muons rarely hit the exact geometric center of scintillator bars and arc scintillators, the actual impact location can be corrected using the amplitude information from the two adjacent bars on either side of the scintillator bar or arc scintillator. When a muon hits a scintillator bar or arc scintillator, it generates fluorescent photons, which are collected by the SiPM to produce amplitude information. The location where the muon hits will generate more fluorescent photons, while the surrounding areas will generate relatively fewer. In other words, the output signal amplitude of the SiPM will be larger at the location where the muon hits, and smaller at the surrounding areas. The charge centroid method can be used to find the geometric centroid, thereby determining the specific location where the muon hits the scintillator bar or arc scintillator.

[0091] This embodiment is basically the same as Embodiment 2, except that step S2 is different:

[0092] S2'. When determining the incident coordinates (x, y, z) and exit coordinates (Ox, Oy, Oz) of the muon based on the positions of the scintillator strips and arc scintillators it hits during incident and exit, the following formula is used to calculate the incident coordinates (x, y, z) and exit coordinates (Ox, Oy, Oz) of the muon:

[0093] When 0 <i<i 总 At -1, If the first scintillator submatrix is ​​not hit during incident, the coordinates are corrected using the adjacent scintillator bars on the left and right sides.

[0094] When i = 0 When the incident light hits the upper edge of the first scintillator submatrix, the coordinates are corrected using only the adjacent scintillator strips on one side.

[0095] when i=i 总 At -1, When the incident light hits the lower edge of the first scintillator submatrix, the coordinates are corrected using only the adjacent scintillator strips on one side.

[0096] When 0 <j<j 总 At -1, If the first scintillator submatrix is ​​not hit during launch, the coordinates are corrected using the adjacent scintillator bars on the left and right sides.

[0097] When j = 0 When it is launched, it hits the upper edge of the first scintillator submatrix. At this time, the coordinates are corrected only by the adjacent scintillator strip on one side.

[0098] When j = j 总 At -1, When it is launched, it hits the upper edge of the first scintillator submatrix. At this time, the coordinates are corrected only by the adjacent scintillator strip on one side.

[0099] When 0 <iz z总 -1 o'clock, If the second scintillator submatrix is ​​not hit during incident, the coordinates are corrected using the adjacent arc-shaped scintillators on the left and right sides.

[0100] when i z When = 0, When the incident object hits the upper edge of the second scintillator submatrix, the coordinates are corrected using only the adjacent arc-shaped scintillator on one side.

[0101] when i z =i z总 At -1, When the incident object hits the lower edge of the second scintillator submatrix, the coordinates are corrected using only the adjacent arc-shaped scintillator on one side.

[0102] When 0 <j z <j z总 At -1, If the second scintillator submatrix is ​​not hit during launch, the coordinates are corrected using the adjacent arc-shaped scintillators on the left and right sides.

[0103] When j z When = 0, When it is launched, it hits the upper edge of the second scintillator submatrix. At this time, the coordinates are corrected only by the adjacent arc-shaped scintillator on one side.

[0104] When j z =j z总 At -1, When it is launched, it hits the lower edge of the second scintillator submatrix. At this time, the coordinates are corrected only by the adjacent arc-shaped scintillator on one side.

[0105] Where R is the distance between the geometric center of the scintillator bar and the centerline of the detector. Let Δω be the angle between the geometric center of the scintillator strip with index 0 and the x-axis, Δω be the difference in angle between two adjacent scintillator strips, Z0 be the z-coordinate of the geometric center of the arc scintillator with index 0, ΔZ be the difference in z-coordinate between two adjacent arc scintillators, and i be the index of the scintillator strip hit by the muon incident. 总 Let i be the total number of scintillator bars in the first scintillator submatrix, i = 0, 1, 2, 3, ..., i 总 -1; j is the index of the scintillator bar hit by the muon during its incident motion, j 总 The total number of scintillator bars in the first scintillator submatrix, j = 0, 1, 2, 3, ..., j 总 -1; i 总 =j 总 i z The number of the arc scintillator hit by the muon during its incident motion, i​z总 i represents the total number of arc-shaped scintillators in the second scintillator submatrix. z =0, 1, 2, 3, ..., i z总 -1; j z j is the serial number of the arc scintillator that the muon hit when it was launched. z总 j represents the total number of arc-shaped scintillators in the second scintillator submatrix. z =0, 1, 2, 3, ..., j z总 -1; i z总 =j z总 E i The signal amplitude generated by the first signal readout device corresponding to the scintillator bar with serial number i. E is the sum of the signal amplitudes generated by the first signal readout device corresponding to the scintillator bar with sequence number i and the scintillator bar adjacent to it. j The signal amplitude generated by the first signal readout device corresponding to the scintillator bar with sequence number j. The sum of the signal amplitudes generated by the first signal readout device corresponding to the scintillator bar with sequence number j and the scintillator bar adjacent to it with sequence number j. For the sequence number i z The signal amplitude generated by the second signal readout device corresponding to the arc-shaped scintillator. For the sequence number i z The arc-shaped scintillator and the one with the serial number i z The sum of the signal amplitudes generated by the second signal readout devices corresponding to the adjacent arc scintillators. For the sequence number j z The signal amplitude generated by the second signal readout device corresponding to the arc-shaped scintillator. For the sequence number j z The arc-shaped scintillator and the one with the serial number j z The sum of the signal amplitudes generated by the second signal readout device corresponding to the adjacent arc scintillators.

[0106] It should also be noted that since the x, y, and z axes all have directions, the calculation formulas should be adjusted according to the actual positive and negative values ​​of the coordinates. Due to the complexity of the situation, to avoid redundancy, this embodiment does not discuss the formulas for each case individually. Those skilled in the art can derive the specific formulas for each case from the above formulas based on basic mathematical knowledge. In addition, different numbering methods will also affect the specific formulas, and formulas derived from the above formulas are also within the scope of protection of this invention.

[0107] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A muon imaging method applied to a drilling-type muon detector, the drilling-type muon detector comprising a cylindrical shell, a first scintillator matrix, and a second scintillator matrix; The first scintillator matrix is ​​disposed on the inner wall of the outer shell and includes two first scintillator sub-matrices with a semi-circular cross-section. The two first scintillator sub-matrices form a tube that matches the shape of the inner wall. The first scintillator sub-matrices are composed of multiple scintillator strips extending along the axial direction of the outer shell arranged in parallel. Each scintillator strip is coupled to a first signal readout device at its end. The second scintillator matrix is ​​located inside the first scintillator matrix and includes four second scintillator sub-matrices extending along the axial direction of the outer shell. The four scintillator sub-matrices form a tubular shape that matches the inner shape of the first scintillator matrix. The scintillator sub-matrices include a plurality of arc-shaped scintillators arranged side by side along the axial direction of the outer shell. Each arc-shaped scintillator has a second signal readout device coupled to its end. Its features are, The muon imaging method includes: The positions of the scintillator strips and arc scintillators struck by the muon during its incident and exit phases are determined based on the magnitude of the signal amplitude generated when the muon hits the detector. The incident coordinates of the muon are determined based on the positions of the scintillator bars and arc scintillators it hits during its incident and exit phases. and exit coordinates ;in, and Determined based on the signal obtained by the first signal readout device, and The origin is determined based on the signal acquired by the second signal readout device; the origin is the midpoint of the detector's centerline. The axial direction is upward when the detector is viewed from above. The axis is to the left of the detector when viewed from above. The axial direction is upward when the detector is viewed directly from the front. Based on the incident coordinates of the muon and exit coordinates Calculate the muon in Vectors along the axis ,exist Vectors along the axis and in Vectors along the axis ; The azimuth angle of the munia can be calculated using the following formula. and zenith : ； ； According to the azimuth angle of Muzi and zenith Obtain muon imaging images; The incident coordinates of the muon are determined by the positions of the scintillator strips and arc scintillators it hits during incident and exit. and exit coordinates This includes calculating the incident coordinates of the muon using the following formula. and exit coordinates : when hour, ; when hour, ; when hour, when hour, ; when hour, ; when hour, ; when hour, ; when hour, ; when hour, ; when hour, ; when hour, ; when hour, ; in, The distance between the geometric center of the scintillator bar and the centerline of the detector is denoted as . The geometric center of the scintillator bar with serial number 0 and The angle between the axes, This represents the difference in angle between two adjacent scintillator bars. The z-coordinate of the geometric center of the arc scintillator with index 0. It represents the difference in z-coordinate between two adjacent arc-shaped scintillators. This refers to the sequence number of the scintillating body bar hit by the muon's initial shot. The total number of scintillator bars in the first scintillator submatrix. ; This refers to the sequence number of the scintillating body bar hit by the muon's initial shot. The total number of scintillator bars in the first scintillator submatrix. ; This is the serial number of the arc scintillator that was hit when the muon was fired. This represents the total number of arc-shaped scintillators in the second scintillator submatrix. ; This is the serial number of the arc-shaped scintillator that the Muzan hit when it was launched. This represents the total number of arc-shaped scintillators in the second scintillator submatrix. ; ; For the serial number The signal amplitude generated by the first signal readout device corresponding to the scintillator bar. For the serial number Scintillator bars and those with serial number The sum of the signal amplitudes generated by the first signal readout device corresponding to adjacent scintillator bars. For the serial number The signal amplitude generated by the first signal readout device corresponding to the scintillator bar. For the serial number Scintillator bars and those with serial number The sum of the signal amplitudes generated by the first signal readout device corresponding to adjacent scintillator bars. For the serial number The signal amplitude generated by the second signal readout device corresponding to the arc-shaped scintillator. For the serial number The arc-shaped scintillator and the one with the serial number The sum of the signal amplitudes generated by the second signal readout devices corresponding to the adjacent arc scintillators. For the serial number The signal amplitude generated by the second signal readout device corresponding to the arc-shaped scintillator. For the serial number The arc-shaped scintillator and the one with the serial number The sum of the signal amplitudes generated by the second signal readout device corresponding to the adjacent arc scintillators.

2. The muon imaging method according to claim 1, characterized in that: The second scintillator matrix has a cavity inside, and a signal processing circuit board is provided inside the cavity. The signal processing circuit board is electrically connected to the first signal readout device and the second signal readout device, respectively.

3. The muon imaging method according to claim 1 or 2, characterized in that: The first signal readout device is coupled to both ends of the scintillator strip.

4. The muon imaging method according to claim 1 or 2, characterized in that: A gap is provided between two adjacent scintillator sub-matrices and the other two adjacent scintillator sub-matrices in the four scintillator sub-matrices, and the second signal readout device is located within the gap.

5. The muon imaging method according to claim 1 or 2, characterized in that, The determination of the positions of the scintillator bars and arc scintillators struck by the muon during its incident and exit phases, based on the magnitude of the signal amplitude generated when the muon hits the detector, includes: When a muon hits the same first scintillator submatrix during both incident and exit, the scintillator strip corresponding to the largest signal amplitude is taken as the scintillator strip hit during the incident phase of the muon, and the scintillator strip corresponding to the second largest signal amplitude is taken as the scintillator strip hit during the exit phase of the muon. When the muon strikes different first scintillator sub-matrices during its incident and exit phases, the two scintillator bars with the largest signal amplitude in the two first scintillator sub-matrices are respectively taken as the two scintillator bars struck by the muon. The two arc scintillators with the largest signal amplitude in the four scintillator sub-matrices are taken as the two arc scintillators hit by the muon. The arc scintillator with the larger Z coordinate value is taken as the arc scintillator hit when the muon is incident, and the arc scintillator with the smaller Z coordinate value is taken as the arc scintillator hit when the muon is exiting.

6. The muon imaging method according to claim 5, characterized in that, The scintillator strips and arc scintillators are pre-numbered sequentially, and the positions of the scintillator strips and arc scintillators that the muon hits during its incident and exit phases are determined according to the sequence numbers.

7. The muon imaging method according to claim 6, characterized in that, The incident coordinates of the muon are determined by the positions of the scintillator bars and arc scintillators it hits during incident and exit. and exit coordinates hour, and Based on the scintillator bar hit by the Muon's incident shot and shaft or The angle between the axes and Sure, Based on the arc scintillator hit by the Muon incident Coordinate values ​​determined; and Based on the scintillator bar that Muzi hit when she was launched and shaft or The angle between the axes and Sure, Based on the arc-shaped scintillator that Muzi hit when it was launched. The coordinate values ​​are determined; among them, denoted as , which is the distance between the geometric center of the scintillator bar and the centerline of the detector.

8. The muon imaging method according to claim 5, characterized in that, If the sum of the signal amplitudes obtained by the first signal readout devices in the two first scintillator sub-matrices is not zero, then the muon will hit different first scintillator sub-matrices when it is incident and when it is emitted; otherwise, the muon will hit the same first scintillator sub-matrices when it is incident and when it is emitted.

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