A method and measurement system for determining the direction of radioactive sources

Abstract

The present invention discloses a method and a measuring system for determining the source of radioactive direction, belonging to the field of radioactive measurement technology, including arranging basic detection units according to a three-dimensional matrix sequence, establishing a three-dimensional coordinate system according to the three-dimensional matrix array, and recording the coordinates of the basic detection units. When the radiation detection data of each basic detection unit in the detector is obtained, the coordinate point data is converted into a Cartesian two-dimensional rectangular coordinate and processed by a radiation detector back-end software processing system to obtain the final shielding body orientation of radiation dose leakage. The present invention uses a spherical coordinate system to establish a three-dimensional matrix sequence radiation detection device, and can use the basic detection units to automatically fit the curve to obtain the ray direction angle, simulate the main source direction of the ray, and form a radiation detector with the ability to quickly measure the ray direction source. The obtained ray direction fitting line is used to determine the shielding body orientation where radiation dose leakage may exist.

Description

Technical Field

[0001] The present invention relates to the technical field of radioactivity measurement, and in particular to a method and a measurement system for determining the direction and source of radioactivity. Background Art

[0002] Ionizing radiation is the phenomenon that rays with direct or indirect ionizing ability propagate into space. Rays have energy, propagation direction, and ionizing ability. For the measurement of ionizing radiation intensity, the current measurement methods all rely on the radiation dose / radiation dose rate at the location of the detector of the radiation detection instrument, which is characterized by physical quantities such as air kerma rate / air absorption dose rate / surrounding dose equivalent rate, and the measurement units are Gy, Gy / h, Sv, Sv / h. For radiation detection instruments, the radiation detection instruments currently used in the world are mainly divided into three major categories: gas ionization chambers, scintillators, and semiconductors. Gas ionization chambers are further divided into ionization chambers, proportional counters, and GM counters. Scintillators are divided into organic scintillators and inorganic scintillators. Semiconductors include high-purity HGe, cadmium zinc telluride, gold silicon surface barrier and other semiconductor detectors.

[0003] Current radiation detection instruments have the following problems:

[0004] 1. The physical quantities measured by current radiation detection instruments all represent the energy absorbed by the unit mass at the location or the energy absorbed by the unit mass per unit time. Taking the radiation detection physical quantity air absorption dose rate as an example, when ionizing radiation propagates in the air, its air absorption dose rate is 1Gy / h, which means that 1 joule of radiation energy is absorbed per kilogram of air per hour. It can be found that the instruments do not reflect the source direction of the measured ionizing radiation.

[0005] 2. Current instruments and equipment do not have the ability to measure the direction of ionizing radiation. Regardless of whether they are ionization chamber type, scintillator type, or semiconductor type, they all rely on radiation detection detectors to absorb ionizing radiation without any azimuth difference, and finally form electrical signals to measure the intensity of ionizing radiation. The only azimuth difference is that the instrument has different angular responses and detection efficiencies for ionizing radiation in different directions, and it is impossible to distinguish the directional source.

[0006] 3. Because of problems 1 and 2, when measuring ionizing radiation, we only know the ionizing radiation intensity at the measured location, but we cannot know which direction the ionizing radiation is mainly directed at, nor can we know the extent to which each direction contributes to the ionizing radiation at that location.

[0007] 4. Problem 3 will lead to new problems in the field of radiation protection. When an obvious ionizing radiation leak is measured, it is impossible to know the direction from which the radiation dose mainly comes and the contribution ratio of each direction, which will make it impossible to determine where the main defects of radiation protection measures and radiation shielding projects come from. This will cause some difficulties in the implementation of the principle of "radiation protection optimization", and the reduction of radiation dose limits will also bring many inconveniences.

[0008] Based on the above, in order to solve this problem, a method and a measurement system for determining the direction of the radioactive source are proposed. Summary of the invention

[0009] The purpose of the present invention is to solve the problems existing in the prior art, and a method and measurement system for determining the directional source of radioactivity is proposed. The method uses a spherical coordinate system to establish a three-dimensional matrix sequence radiation detection device, which can use basic detection units to automatically fit curves to obtain ray direction angles, simulate the direction of the main source of rays, and form a radiation detector with the ability to quickly measure the directional source of rays. The obtained ray direction fitting line is used to determine the orientation of a shielding body where radiation dose leakage may exist.

[0010] In order to achieve the above object, the present invention adopts the following technical solutions:

[0011] A method and a measuring system for determining the direction of a radioactive source, including a determination method, wherein the determination method is as follows:

[0012] S1. Establish a basic detection unit: Use the GM counter tube as the basic detection unit for radiation dose rate detection. The basic detection unit can independently detect the radiation dose rate and save the detected data through data units;

[0013] S2. Establishing a detection set: Arranging the basic detection units in a three-dimensional matrix sequence to form a detection set in the form of a three-dimensional matrix array, reducing the maximum limit of the geometric size of the detection set, keeping the dose rate difference caused by the distance in the detection set within an acceptable range, and the formed detection set is used as the detector of the radiation detection instrument;

[0014] S3. Establish a three-dimensional coordinate system: take the central basic detection unit of the detection set as the origin, establish a three-dimensional rectangular coordinate system, and position the three-dimensional rectangular coordinate system so that each basic detection unit has a unique coordinate (x, y, z) in this coordinate system, and the coordinate point scale of the positioning is at the center of the detection area of ​​the basic detection unit;

[0015] Let the basic detection unit coordinate y=0, and get the rectangular coordinate of the xz plane, z=ax, and we can get θ=arctan(a);

[0016] Let the basic detection unit coordinate x=0, and get the rectangular coordinate of the yz plane, z=by; we can get φ=arctan(b);

[0017] Get the direction angles θ and φ of the fitting line;

[0018] The detection data obtained by the detector is transmitted to the back-end software processing system of the radiation detector through the data line. With the detector as the center of the circle, the fitting line direction angles θ, φ and the characteristic dose rate value are added to obtain the main direction source of the ray and the dose rate value;

[0019] Using the obtained ray direction and dose rate value, determine the shielding body position where radiation dose leakage may occur;

[0020] S4. Set up a shielding layer: add a radiation shielding layer to the detector shell. The radiation shielding layer forms receiving holes in the three coordinate axis directions of X, Y, and Z corresponding to the coordinate axis where the basic detection unit is located, so as to prevent the radiation exceeding the cross-sectional range of the detector from ionizing all the basic detection units in a large area;

[0021] S5. Dose rate data extraction: Through the radiation detection data of each basic detection unit in the detector, the data processing unit is used to extract the data point with the highest dose rate, record the dose rate M of the batch of basic measurement units, and match the basic detection unit corresponding to the detection data;

[0022] S6, coordinate point screening and fitting: perform a preliminary linear fitting on the coordinate points corresponding to the matched basic detection units, remove the coordinate points that obviously deviate from the fitting line, and then perform a second linear fitting to obtain the coordinate points of the final fitting line;

[0023] S7. Measurement, calculation and judgment: The obtained fitting line coordinates are successively processed through Cartesian two-dimensional rectangular coordinate conversion and the radiation detector back-end software processing system to determine the orientation of the shielding body where radiation dose leakage may occur.

[0024] Preferably, in said S3, each basic detection unit in the three-dimensional coordinate system needs to be evenly arranged in the three-dimensional rectangular coordinate system, and the spacing between the basic detection units is the same.

[0025] Preferably, the S4 sets up receiving holes on the radiation shielding layer at positions corresponding to the basic detection units in the shielding layer, which can realize detection while preventing the radiation exceeding the cross-sectional range of the detector from ionizing all the basic detection units of a large area.

[0026] A method for determining the direction of a radioactive source proposes a measurement system, characterized in that the measurement system includes Cartesian two-dimensional rectangular coordinate conversion and data determination:

[0027] The Cartesian two-dimensional rectangular coordinate conversion:

[0028] Let the basic detection unit coordinate y=0, and get the rectangular coordinate of the xz plane, z=ax, and we can get θ=arctan(a);

[0029] Let the basic detection unit coordinate x=0, and get the rectangular coordinate of the yz plane, z=by; we can get φ=arctan(b);

[0030] Get the fitting line direction angle θ, φ;

[0031] The data determination transmits the detection data obtained by the detector to the back-end software processing system of the radiation detector through the data line, takes the detector as the center of the circle, adds the fitting line direction angle θ, φ and the characteristic dose rate value, and obtains the main direction source of the ray and the dose rate value;

[0032] The obtained ray direction and dose rate value are used to determine the orientation of the shielding body where radiation dose leakage may occur.

[0033] Preferably, for the fitting lines obtained by the Cartesian two-dimensional rectangular coordinate conversion, if there are overlapping points of basic detection units corresponding to multiple fitting lines, the radiation detection data of the basic detection units should be calculated by superposition.

[0034] Compared with the prior art, the present invention has the following beneficial effects:

[0035] This scheme uses a spherical coordinate system to establish a three-dimensional matrix sequence radiation detection device, which can use basic detection units to automatically fit curves, obtain ray direction angles, simulate the direction of the main source of rays, and form a radiation detector with the ability to quickly measure the direction of the ray source. The obtained ray direction fitting line is used to determine the orientation of the shielding body where radiation dose leakage may exist. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] Figure 1 A schematic flow chart of a method for determining the direction of a radioactive source proposed by the present invention;

[0037] Figure 2 This is a schematic diagram of a model of a method for determining the directional source of radioactivity and a measurement system proposed by the present invention. DETAILED DESCRIPTION

[0038] The technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0039] Example

[0040] Reference Figure 1-2 , a method and measurement system for determining the direction of radioactive sources, including a determination method, the determination method is as follows:

[0041] Establish a basic detection unit: Use the GM counter tube as the basic detection unit for radiation dose rate detection. The basic detection unit can independently detect the radiation dose rate and save the detected data through data units;

[0042] Establishing a detection set: Arranging the basic detection units in a three-dimensional matrix sequence to form a detection set in the form of a three-dimensional matrix array, reducing the maximum limit of the geometric size of the detection set, keeping the dose rate difference caused by the distance in the detection set within an acceptable range, and the formed detection set is used as the detector of the radiation detection instrument;

[0043] It should be noted that the GM counter tube is small and light, which can minimize costs.

[0044] Establish a three-dimensional coordinate system: Take the central basic detection unit of the detection set as the origin, establish a three-dimensional rectangular coordinate system, and position the three-dimensional rectangular coordinate system so that each basic detection unit has a unique coordinate (x, y, z) in this coordinate system. The coordinate point scale of the positioning is at the center of the detection area of ​​the basic detection unit;

[0045] Based on the above, each basic detection unit needs to be arranged evenly in a three-dimensional rectangular coordinate system, and the spacing between the basic detection units is the same.

[0046] Establish a shielding layer: add a radiation shielding layer to the detector shell, and the radiation shielding layer forms receiving holes in the directions of the three coordinate axes of X, Y, and Z corresponding to the coordinate axis where the basic detection unit is located;

[0047] Based on the above, receiving holes are set on the radiation shielding layer at the corresponding positions of the basic detection units, which can realize detection while preventing the rays exceeding the cross-sectional range of the detector from ionizing all the basic detection units in a large area.

[0048] Dose rate data extraction: Through the radiation detection data of each basic detection unit in the detector, the data processing unit is used to extract the data point with the highest dose rate, record the dose rate M of the batch of basic measurement units, and match the basic detection unit corresponding to the detection data;

[0049] Coordinate point screening and fitting: Perform a preliminary linear fitting on the coordinate points corresponding to the matching basic detection units, remove the coordinate points that obviously deviate from the fitting line, and then perform a second linear fitting to obtain the coordinate points of the final fitting line;

[0050] Measurement, calculation and judgment: The obtained fitting line coordinates are processed by Cartesian two-dimensional rectangular coordinate conversion and the radiation detector back-end software processing system in turn to determine the orientation of the shielding body where radiation dose leakage may occur;

[0051] The detection data obtained by the detector is transmitted to the back-end software processing system of the radiation detector through a data line. With the detector as the center of the circle, the fitting line direction angles θ, φ and the characteristic dose rate value are added to obtain the main direction source of the rays and the dose rate value.

[0052] The obtained ray direction and dose rate value are used to determine the orientation of the shielding body where radiation dose leakage may occur.

[0053] The measurement system includes Cartesian 2D rectangular coordinate conversion and data determination:

[0054] Cartesian 2D rectangular coordinate transformation:

[0055] Let the basic detection unit coordinate y=0, and get the rectangular coordinate of the xz plane, z=ax, and we can get θ=arctan(a);

[0056] Let the basic detection unit coordinate x=0, and get the rectangular coordinate of the yz plane, z=by; we can get φ=arctan(b);

[0057] Get the direction angles θ and φ of the fitting line;

[0058] Data determination: The detection data obtained by the detector is transmitted to the back-end software processing system of the radiation detector through the data line. With the detector as the center of the circle, the direction angles θ and φ of the fitting line and the characteristic dose rate value are added to obtain the main direction source of the ray and the dose rate value;

[0059] The obtained ray direction and dose rate value are used to determine the orientation of the shielding body where radiation dose leakage may occur. For the basic detection units corresponding to multiple fitting lines that overlap, the radiation detection data of the basic detection units should be calculated by superposition.

[0060] When the present invention is in use, a GM counter tube is used as a basic detection unit for radiation dose rate detection to establish a three-dimensional coordinate system according to a three-dimensional matrix array, and the coordinates of the basic detection units are recorded. When the radiation detection data of each basic detection unit in the detector is obtained by the ray, the coordinate point data is converted into a Cartesian two-dimensional rectangular coordinate and processed by the back-end software processing system of the radiation detector to obtain the final shielding body orientation of the radiation dose leakage.

[0061] The above description is only a preferred specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can make equivalent replacements or changes according to the technical scheme and inventive concept of the present invention within the technical scope disclosed by the present invention, which should be covered by the protection scope of the present invention.

Claims

1. A method for determining the direction of radioactive sources, characterized in that: The method includes the following determination method: S1. Establish a basic detection unit: Use the GM counter tube as the basic detection unit for radiation dose rate detection. The basic detection unit can independently detect the radiation dose rate and save the detected data through data units; S2. Establishing a detection set: Arranging the basic detection units in a three-dimensional matrix sequence to form a detection set in the form of a three-dimensional matrix array, reducing the maximum limit of the geometric size of the detection set, keeping the dose rate difference caused by the distance in the detection set within an acceptable range, and the formed detection set is used as the detector of the radiation detection instrument; S3. Establish a three-dimensional coordinate system: take the central basic detection unit of the detection set as the origin, establish a three-dimensional rectangular coordinate system, and position the three-dimensional rectangular coordinate system so that each basic detection unit has a unique coordinate (x, y, z) in this coordinate system, and the coordinate point scale of the positioning is at the center of the detection area of ​​the basic detection unit; Let the basic detection unit coordinate y=0, and get the rectangular coordinate of the xz plane, z=ax, and we can get θ=arctan(a); Let the basic detection unit coordinate x=0, and get the rectangular coordinate of the yz plane, z=by; we can get φ=arctan(b); Get the fitting line direction angle θ, φ; The detection data obtained by the detector is transmitted to the back-end software processing system of the radiation detector through the data line. With the detector as the center of the circle, the fitting line direction angles θ, φ and the characteristic dose rate value are added to obtain the main direction source of the ray and the dose rate value; Using the obtained ray direction and dose rate value, determine the shielding body position where radiation dose leakage may occur; S4. Set up a shielding layer: add a radiation shielding layer to the detector shell. The radiation shielding layer forms receiving holes in the three coordinate axis directions of X, Y, and Z corresponding to the coordinate axis where the basic detection unit is located, so as to prevent the radiation exceeding the cross-sectional range of the detector from ionizing all the basic detection units in a large area; S5. Dose rate data extraction: Through the radiation detection data of each basic detection unit in the detector, the data processing unit is used to extract the data point with the highest dose rate, record the dose rate M of the batch of basic measurement units, and match the basic detection unit corresponding to the detection data; S6, coordinate point screening and fitting: perform a preliminary linear fitting on the coordinate points corresponding to the matched basic detection units, remove the coordinate points that obviously deviate from the fitting line, and then perform a second linear fitting to obtain the coordinate points of the final fitting line; S7. Measurement, calculation and judgment: The obtained fitting line coordinates are successively processed through Cartesian two-dimensional rectangular coordinate conversion and the radiation detector back-end software processing system to determine the orientation of the shielding body where radiation dose leakage may occur.

2. A method for determining the direction of radioactive sources according to claim 1, characterized in that: The S3 establishes that each basic detection unit in the three-dimensional coordinate system needs to be evenly arranged in the three-dimensional rectangular coordinate system, and the spacing between the basic detection units is the same.

3. A method for determining the direction of radioactive sources according to claim 1, characterized in that: The S4 sets up receiving holes on the radiation shielding layer at positions corresponding to the basic detection units in the shielding layer, which can realize detection while preventing the radiation exceeding the cross-sectional range of the detector from ionizing all the basic detection units in a large area.

4. A measurement system according to a method for determining the direction of radioactive sources according to claims 1-3, characterized in that: The measurement system includes Cartesian two-dimensional rectangular coordinate conversion and data determination: The Cartesian two-dimensional rectangular coordinate conversion: Let the basic detection unit coordinate y=0, and get the rectangular coordinate of the xz plane, z=ax, and we can get θ=arctan(a); Let the basic detection unit coordinate x=0, and get the rectangular coordinate of the yz plane, z=by; we can get φ=arctan(b); Get the direction angles θ and φ of the fitting line; The data determination transmits the detection data obtained by the detector to the back-end software processing system of the radiation detector through the data line, takes the detector as the center of the circle, adds the fitting line direction angle θ, φ and the characteristic dose rate value, and obtains the main direction source of the ray and the dose rate value; The obtained ray direction and dose rate value are used to determine the orientation of the shielding body where radiation dose leakage may occur.

5. A measurement system for determining the direction of radioactive sources according to claim 4, characterized in that: The fitting line is obtained through Cartesian two-dimensional rectangular coordinate transformation. For the overlapping points of basic detection units corresponding to multiple fitting lines, the radiation detection data of the basic detection units should be calculated by superposition.

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