Device and method for positioning gamma radiation source

Abstract

The invention provides a device and method for positioning a gamma radiation source, and relates to the technical field of radiation monitoring. The device comprises a gamma dose rate instrument used for measuring the gamma radiation air absorption dose rate; the bracket is used for supporting and moving the gamma dose rate instrument, so that the gamma dose rate instrument can rotate in the horizontal direction; the shielding plate is arranged on the bracket, can coaxially rotate with the gamma dose rate instrument and is used for continuously shielding radiation on one side of the back of the gamma dose rate instrument; and the control module is used for acquiring measurement data of the gamma dose rate instrument and controlling the rotation angle of the bracket. According to the technical scheme, the target radioactive source can be positioned and the activity can be estimated at low cost.

Description

Technical Field

[0001] The present application relates to the field of radiation monitoring technology, and in particular to a device and method for locating a gamma radiation source. Background Art

[0002] In the fields of nuclear energy utilization and radiation protection, gamma radiation, as a highly penetrating electromagnetic radiation, is widely used in various fields, including medical treatment, scientific research, and industrial flaw detection. However, when gamma radiation sources are out of control or not properly managed, they can pose a serious threat to human health and environmental safety.

[0003] To ensure personnel safety during radiation emergencies, a complete search for radioactive sources often requires determining the source's location and estimating its distance and activity. Currently, the following methods are commonly used to locate radioactive sources: one method uses a gamma camera for precise positioning, but this is expensive and inconvenient for emergency use; another method relies on manual instrumentation to measure extreme values to determine the source's location, but this method has low accuracy and cannot estimate the source's distance from a single measurement. Summary of the Invention

[0004] In order to solve the above problems, the present application provides a device and method for locating a gamma radiation source, which can locate the target radiation source and estimate its activity at a low cost.

[0005] This application is implemented as follows:

[0006] In a first aspect, the present application provides a device for locating a gamma radiation source, comprising: a gamma dose rate meter for measuring the gamma radiation air absorption dose rate; a bracket for supporting and moving the gamma dose rate meter so that the gamma dose rate meter can rotate in a horizontal direction; a shielding plate provided on the bracket and capable of coaxially rotating with the gamma dose rate meter to continuously shield the radiation on the rear side of the gamma dose rate meter; and a control module for obtaining measurement data of the gamma dose rate meter and controlling the rotation angle of the bracket.

[0007] Furthermore, based on the above solution, a laser emitter parallel to the gamma dose rate meter is also provided on the bracket to indicate the direction of the target radiation source.

[0008] Furthermore, based on the above solution, the bracket includes a lifting structure, so that when the bracket is lifted or lowered by the lifting structure, the gamma dose rate meter can be driven to be lifted or lowered in a vertical direction.

[0009] Furthermore, based on the above solution, the control module is also used to collect meteorological parameters, geographical location information and the rotation angle of the bracket.

[0010] In a second aspect, the present application provides a method for locating a gamma radiation source, which is applied to any device for locating a gamma radiation source described in the first aspect, the method comprising: outside the target radiation field, using a gamma dose rate meter to measure and record the background value of the air absorption dose rate; placing the device for locating the gamma radiation source in the target radiation field, rotating the gamma dose rate meter one circle to determine the direction in which the value of the gamma radiation air absorption dose rate is minimum, the opposite side of the direction is recorded as the direction of the target radiation source, and measuring the gamma radiation air absorption dose rate in the direction and on its opposite side, respectively, and recorded as a first measurement value and a second measurement value, respectively; estimating the distance value of the target radiation source based on the first measurement value, the second measurement value and a preset distance value, wherein the preset distance value is a value determined based on the rotation range of the gamma dose rate meter; and estimating the activity value of the target radiation source based on the background value of the air absorption dose rate, the second measurement value and the estimated distance value to the target radiation source.

[0011] Furthermore, based on the above solution, the method further includes sending detection information of the target radiation source to a designated terminal device, wherein the detection information includes the direction of the target radiation source and the estimated distance value and activity value of the target radiation source.

[0012] Furthermore, based on the above solution, the bracket includes a lifting structure, so that when the bracket is lifted or lowered by the lifting structure, it can drive the gamma dose rate meter to rise or fall in the vertical direction. Before the step of rotating the gamma dose rate meter one circle to determine the orientation at which the gamma radiation air absorption dose rate value is minimum, the method further includes: fixing the rotation angle of the gamma dose rate meter and adjusting its vertical position using the lifting structure until the height corresponding to the maximum gamma radiation air absorption dose rate value is reached.

[0013] Furthermore, based on the above solution, the calculation formula used to estimate the distance value of the target radiation source based on the first measurement value, the second measurement value and the preset distance value includes: Wherein d1 is the estimated distance value of the target radiation source, d is the preset distance value, D1 is the first measurement value, and D2 is the second measurement value.

[0014] Furthermore, based on the above solution, the calculation formula used to estimate the activity value of the target radiation source based on the background value of the air absorption dose rate, the second measurement value and the estimated distance value of the target radiation source includes: Where A is the estimated activity value of the target radiation source, D0 is the background value of the air absorption dose rate, Γ δ is the air kerma rate constant.

[0015] Compared with the prior art, this application has at least the following advantages or beneficial effects:

[0016] Through the combined design of rotational scanning and background radiation shielding, this technical solution can more accurately identify the direction of the highest radiation intensity, thereby achieving precise positioning of the gamma radiation source. This not only improves the accuracy of positioning, but also enhances the reliability of the data, providing strong support for subsequent emergency response and radiation protection. In addition to precise positioning, this technical solution can also estimate the distance and activity value of the target radiation source. Due to the use of a relatively low-cost gamma dose rate meter, this technical solution is not only suitable for rapid response in emergency scenarios, but can also be widely used in daily radiation monitoring, scientific research experiments, industrial flaw detection and other fields, and has broad market prospects and application value. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the following is a brief introduction to the drawings required for use in the embodiments. It should be understood that the following drawings only show certain embodiments of the present application and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other relevant drawings can be obtained based on these drawings without creative work.

[0018] Figure 1 This is a structural schematic diagram of an embodiment of a device for locating a gamma radiation source according to the present application;

[0019] Figure 2 This is a flow chart of an embodiment of a method for locating a gamma radiation source according to the present application;

[0020] Figure 3 FIG. 1 is a schematic diagram of estimating the position of a radiation source according to an embodiment of the present application.

[0021] Icons: 100, gamma dose rate meter; 200, bracket; 300, shielding plate; 400, laser emitter. DETAILED DESCRIPTION

[0022] To make the objectives, technical solutions, and advantages of the embodiments of the present application more clear, the technical solutions in the embodiments of the present application will be clearly and completely described below in conjunction with the accompanying drawings of the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Generally, the components of the embodiments of the present application described and shown in the drawings herein can be arranged and designed in various different configurations.

[0023] Therefore, the following detailed description of the embodiments of the present application provided in the accompanying drawings is not intended to limit the scope of the present application for protection, but merely represents selected embodiments of the present application. All other embodiments obtained by persons of ordinary skill in the art based on the embodiments in the present application without creative work are within the scope of protection of the present application.

[0024] Example:

[0025] The following describes some embodiments of the present application in detail with reference to the accompanying drawings. In the absence of conflict, the following embodiments and features thereof may be combined with each other.

[0026] Precisely locating gamma radiation sources is crucial for ensuring personal safety and protecting the environment. However, existing technologies, such as gamma cameras, offer high accuracy, but their high cost makes them difficult to deploy quickly in emergency situations, limiting their widespread use as a response tool. Traditional manual handheld instrumentation, which locates radiation extremes, is not only time-consuming and labor-intensive but also subject to significant human error and low positioning accuracy. More importantly, this method cannot effectively estimate the specific distance to the radiation source, hindering the development of effective emergency response measures.

[0027] To this end, an embodiment of the present application provides a device for locating a gamma radiation source, which can not only meet the requirements of locating a target radiation source and estimating its activity, but is also cost-effective.

[0028] like Figure 1 As shown, the device for locating a gamma radiation source includes a gamma dose rate meter 100 for measuring the gamma radiation air absorption dose rate; a bracket 200 for supporting and moving the gamma dose rate meter 100 so that the gamma dose rate meter 100 can rotate in the horizontal direction; a shielding plate 300, which is provided on the bracket 200 and can rotate coaxially with the gamma dose rate meter 100 to continuously shield the radiation on the back side of the gamma dose rate meter 100; and a control module for obtaining measurement data of the gamma dose rate meter 100 and controlling the rotation angle of the bracket 200.

[0029] In the above embodiment, a gamma dose rate meter 100 (e.g., an FH40G+FHZ672E-10, ATOMTEX AT1123, or a dose rate meter with radionuclide identification) is first used as the core sensor to continuously measure the ambient gamma radiation air absorption dose rate, providing basic data for positioning. Secondly, a support 200 mechanically drives the gamma dose rate meter 100 to rotate horizontally, achieving omnidirectional radiation scanning. Simultaneously, a shielding plate 300, rotating coaxially with the gamma dose rate meter 100, continuously shields radiation from the instrument's rear side, effectively eliminating radiation interference from non-detection directions and improving measurement accuracy. The control module, acting as the central processing unit, is responsible for acquiring real-time measurement data from the gamma dose rate meter 100 and, based on this data, controlling the rotation angle of the support 200 to achieve automated scanning. During the scanning process, the control module records and analyzes radiation intensity values at different angles, comparing them to identify the directions with the highest or lowest radiation intensity (on opposite sides), thereby determining the direction of the target radiation source. The system then uses a preset distance estimation formula and rotation range (i.e., the preset distance value) combined with the minimum and maximum radiation intensity values to estimate the approximate distance to the target radiation source. Finally, the activity value of the target radiation source is further estimated by combining the background value of the air absorbed dose rate and a preset activity estimation formula.

[0030] It should be noted that a mobile terminal device can be further introduced to wirelessly connect the mobile terminal device to the control module, so that the entire device can be controlled on the mobile terminal device, which can ensure the safety of relevant personnel. And ultimately, by sending the detection information (including the direction, distance value and activity value of the target radiation source) in real time to a designated terminal device, such as an emergency command center, a system or mobile device of a safety supervision department, etc., it is possible to realize the instant sharing of radiation source detection information. This means that relevant personnel can obtain key information about the radiation source almost simultaneously without waiting for on-site personnel to return reports or manually upload data. This real-time information sharing mechanism greatly shortens the time for information transmission and provides strong support for rapid response and decision-making.

[0031] In the above embodiment, the use of a relatively low-cost gamma dose rate meter 100 avoids the need for an expensive gamma camera, thereby reducing the overall device cost and making it more suitable for emergency and routine monitoring scenarios. Furthermore, the combined design of the rotating bracket 200 and the shielding plate 300 enables omnidirectional scanning of the gamma dose rate meter 100 and effective shielding of background radiation. Specifically, the shielding plate 300, mounted on the bracket 200 and coaxially rotating with the gamma dose rate meter 100, continuously shields radiation from the back side of the gamma dose rate meter 100, effectively reducing radiation interference from non-detection directions. This allows for more accurate identification of the direction of highest radiation intensity, thereby precisely locating the source of gamma radiation. This design improves measurement accuracy and makes the location of radiation sources more accurate and reliable.

[0032] When determining the direction of the target radiation source, the direction of the target radiation source can be determined by the orientation of the gamma dose rate meter 100 when the measured gamma radiation air absorption dose rate is the maximum, or by the direction opposite to the orientation when the gamma radiation air absorption dose rate is the minimum. After determining the target radiation source, the distance to the target radiation source can be estimated using a preset distance estimation formula based on the minimum (hereinafter referred to as the first measurement value) and maximum (hereinafter referred to as the second measurement value) gamma radiation air absorption dose rate values measured by the gamma dose rate meter 100, combined with a preset distance value. The preset distance value is determined based on the rotation range of the gamma dose rate meter 100 and is typically set to the diameter of a circle formed by one horizontal rotation of the gamma dose rate meter 100. Next, based on the estimated distance to the target radiation source, the activity value of the target radiation source can be estimated using a preset activity estimation formula in combination with the background value of the air absorption dose rate (measured by the gamma dose rate meter 100 in the same environmental area not affected by the target radiation source). In this way, the direction, distance and activity data of the target radiation source can be estimated more accurately.

[0033] It should be noted that obtaining the measurement data of the gamma dose rate meter 100 and controlling the rotation angle of the bracket 200 can be automatically controlled and processed by the control module, which can reduce the risk of direct exposure of personnel to the radiation environment and protect the safety of operators.

[0034] In summary, in the above embodiment, through the combined design of rotational scanning and background radiation shielding, the technical solution can more accurately identify the direction of the highest radiation intensity, thereby achieving precise positioning of the gamma radiation source. This not only improves the accuracy of positioning, but also enhances the reliability of the data, providing strong support for subsequent emergency response and radiation protection. In addition to precise positioning, the technical solution can also estimate the distance and activity value of the target radiation source. Due to the use of a relatively low-cost gamma dose rate meter 100, the technical solution is not only suitable for rapid response in emergency scenarios, but can also be widely used in daily radiation monitoring, scientific research experiments, industrial flaw detection and other fields, and has broad market prospects and application value.

[0035] like Figure 1 As shown, in some embodiments of the present application, the bracket 200 is further provided with a laser emitter 400 parallel to the gamma dose rate meter 100 for indicating the direction of the target radiation source.

[0036] Traditional radiation source positioning methods often rely on complex data analysis and instrument readings, which can be difficult for non-professionals to quickly understand and operate. The above-described embodiment, by introducing a laser emitter 400, achieves intuitive indication of positioning results. The laser emitter 400 can point in real time in the direction of the highest (or opposite to the lowest) radiation intensity detected by the gamma dose rate meter 100, i.e., the direction of the target radiation source. This design converts complex radiation intensity data into intuitive visual indications, greatly reducing the difficulty of operation.

[0037] In emergency situations, quickly and accurately locating a radiation source is crucial. The instant indication function of the laser transmitter 400 can quickly guide emergency personnel or equipment to the radiation source, thereby shortening response time and improving emergency response efficiency. Furthermore, minimizing personnel exposure time in radiation environments is crucial for protecting operator safety. The laser transmitter 400 allows operators to determine the location of the radiation source from a distance by observing the direction of the laser beam, eliminating the need for close proximity to the radiation source and reducing operational risks.

[0038] In some embodiments of the present application, the bracket 200 includes a lifting structure, so that when the bracket 200 is lifted or lowered by the lifting structure, the gamma dose rate meter 100 can be driven to lift or lower in a vertical direction.

[0039] Conventional radiation source location methods are often limited to horizontal scanning, while ignoring vertical variations. In the above embodiment, by introducing a lifting structure, the gamma dose rate meter 100 can more comprehensively cover potential radiation source locations, reducing positioning errors caused by ignoring vertical variations and improving positioning accuracy and comprehensiveness.

[0040] It also makes it easier to adapt to diverse environmental needs: different application scenarios may require different detection heights. For example, radiation monitoring in high-rise buildings or large facilities may require measurements at different floors or heights. The addition of a lifting mechanism allows the bracket 200 to flexibly adjust its height to meet detection needs in various complex environments.

[0041] In some embodiments of the present application, the control module is further configured to collect meteorological parameters, geographic location information, and the rotation angle of the bracket 200 .

[0042] By collecting geographic location information, the location information of the radiation source can be further combined with the estimated location information of the radiation source to convert the location information of the radiation source into geographic location information, which is convenient for relevant personnel to understand and consult. Since meteorological parameters (such as temperature, humidity, air pressure, etc.) not only affect the propagation and attenuation of radiation, they may also interfere with the identification and positioning of the radiation source. By collecting these data in real time through the control module, more comprehensive environmental background information can be provided for subsequent radiation source analysis and positioning. At the same time, the rotation angle of the bracket 200 is one of the key parameters for locating the radiation source. By accurately recording the rotation angle of the bracket 200 through the control module, it can be ensured that the measurement data can be accurately matched with the corresponding spatial position during data analysis, thereby improving the accuracy of locating the radiation source.

[0043] like Figure 2 As shown, an embodiment of the present application further provides a method for applying any of the above-mentioned devices for locating a gamma radiation source, the method comprising the following steps:

[0044] Step S101: Outside the target radiation field, use the gamma dose rate meter 100 to measure and record the background value of the air absorption dose rate.

[0045] At a location far from the target radiation source (i.e., "outside the target radiation field"), a gamma dose rate meter 100 is used to measure the radiation dose rate in the surrounding air. The purpose of this step is to obtain a baseline value with no (or very low) radiation interference, namely the "air absorbed dose rate background value." This value represents the natural radiation level in the absence of the target radiation source and serves as an important reference for subsequent measurements and calculations.

[0046] Step S102: Place the device for locating the gamma radiation source in the target radiation field, rotate the gamma dose rate meter 100 one circle to determine the direction when the gamma radiation air absorption dose rate is the smallest. The opposite side of this direction is recorded as the direction of the target radiation source, and measure the gamma radiation air absorption dose rate in this direction and on its opposite side, respectively, and record them as the first measurement value and the second measurement value, respectively.

[0047] Bring the positioning device containing the gamma dose rate meter 100 into the target radiation field, and then rotate the gamma dose rate meter 100 one circle (or directly rotate the entire device one circle). During the rotation process, the gamma dose rate meter 100 will continuously record the radiation dose rate in various directions. Since the radiation intensity is the greatest in the direction of the radiation source, the dose rate value will show a direction corresponding to a minimum value (or "valley value"), and the opposite side of this direction (the direction after rotating 180°) is the approximate direction of the radiation source. In order to further improve the positioning accuracy, precise measurements are performed in this direction (denoted as "toward A") and its opposite side (denoted as "toward B", that is, the positive and negative sides of the radiation source direction), and a first measurement value (dose rate in the direction of A) and a second measurement value (dose rate in the direction of B) will be obtained.

[0048] Step S103: estimating the distance value of the target radiation source according to the first measurement value, the second measurement value, and a preset distance value, wherein the preset distance value is a value determined according to the rotation range of the gamma dose rate meter 100;

[0049] The first measurement value (dose rate in the direction of the non-radiation source), the second measurement value (dose rate in the direction of the radiation source), and a preset distance value (this value is determined based on the rotation range of the gamma dose rate meter 100 and is generally set to the diameter of the circle formed by the gamma dose rate meter 100 rotating in the horizontal direction) are used to perform a calculation using a specific algorithm or mathematical model. This calculation process takes into account the attenuation characteristics of radiation in air and the relationship between dose rate and distance, thereby estimating the distance between the target radiation source and the measurement point.

[0050] It should be noted that the first measurement value is the result obtained after being shielded by the shielding plate 300 and the body of the gamma dose rate meter 100 and needs to be corrected to the result under unshielded conditions. For example, the correction can be performed as follows: the shielding plate 300 and the body of the gamma dose rate meter 100 are treated as fixed shielding bodies, and the entire device for locating gamma radiation sources is placed in a specific standard field for calibration. The measurement results under unshielded and shielded conditions are obtained, and the ratio of these results is the correction factor. Furthermore, calibration can be performed in different nuclide radiation fields, thereby obtaining multiple corresponding correction factors applicable to radiation fields of different energies.

[0051] Step S104: estimating the activity value of the target radiation source according to the background value of the air absorbed dose rate, the second measurement value, and the estimated distance value of the target radiation source.

[0052] Based on the known background value of the air absorbed dose rate (obtained in step S101), the second measured value (the precise dose rate in the direction of the radiation source), and the estimated distance to the target radiation source (obtained in step S103), a calculation is performed using relevant knowledge such as radiation propagation theory and attenuation formulas. This calculation process considers the relationship between the radiation intensity (i.e., activity) emitted by the radiation source and the radiation dose rate received at the measurement point, as well as the attenuation characteristics of radiation during propagation, thereby estimating the activity value of the target radiation source.

[0053] In summary, in the above embodiment, the gamma dose rate meter 100 is first rotated once, and the maximum value of the radiation intensity in the direction of the radiation source is used to quickly determine the approximate direction of the radiation source. Then, by introducing a preset distance value (determined based on the rotation range factor of the gamma dose rate meter 100) and a specific algorithm or mathematical model, the distance to the target radiation source is estimated. At the same time, the activity value of the radiation source is further estimated by combining the background value of the air absorption dose rate, the second measurement value, and the estimated distance value. This not only enriches the dimensions of obtaining radiation source information, but also provides a more comprehensive and accurate decision-making basis for emergency response.

[0054] It should be understood that although Figure 2 The steps in the flowchart are shown in sequence as indicated by the arrows, but these steps are not necessarily executed in the order indicated by the arrows. Unless otherwise specified in this document, there is no strict order restriction for the execution of these steps, and these steps can be executed in other orders. In addition, Figure 2 At least part of the steps may include multiple sub-steps or multiple stages. These sub-steps or stages are not necessarily executed at the same time, but can be executed at different times. The execution order of these sub-steps or stages is not necessarily sequential, but can be executed in turn or alternately with other steps or at least part of the sub-steps or stages of other steps.

[0055] In some embodiments of the present application, the method further includes sending detection information of the target radiation source to a designated terminal device, where the detection information includes the direction of the target radiation source and the estimated distance value and activity value of the target radiation source.

[0056] In the above embodiment, by sending detection information (including the direction, distance, and activity value of the target radiation source) in real time to designated terminal devices, such as emergency command centers, safety supervision departments' systems, or mobile devices, instant sharing of radiation source detection information is achieved. This means that relevant personnel can obtain key information about the radiation source almost instantly, without having to wait for on-site personnel to return reports or manually upload data. This real-time information sharing mechanism greatly shortens the time it takes to transmit information, providing strong support for rapid response and decision-making.

[0057] In some embodiments of the present application, the bracket 200 includes a lifting structure, so that when the bracket 200 is lifted and lowered by the lifting structure, it can drive the gamma dose rate meter 100 to lift and lower in the vertical direction; before the step of rotating the gamma dose rate meter 100 for one circle to determine the orientation when the value of the gamma radiation air absorption dose rate is minimum, it also includes: fixing the rotation angle of the gamma dose rate meter 100, and adjusting its vertical position through the lifting structure until it reaches the height corresponding to the maximum value of the gamma radiation air absorption dose rate.

[0058] Radiation sources may be located at different heights in space, a dimension often overlooked by conventional radiation source location methods. In the aforementioned embodiment, by introducing a lifting mechanism, the vertical position of the gamma dose rate meter 100 can be precisely adjusted, allowing measurements to be performed at the height of the radiation source. This allows the gamma dose rate meter 100 to be rotated to find the orientation with the lowest radiation intensity, more accurately pointing in the true direction of the radiation source, thereby improving location accuracy.

[0059] Prior to the rotational measurement, the gamma dose rate meter 100 is first adjusted to the height corresponding to the maximum radiation intensity using the lifting mechanism. This process is essentially a rough positioning process. This helps narrow the search range for subsequent rotational measurements, making the rotational measurement more targeted and efficient. Because the gamma dose rate meter 100 receives the highest radiation intensity when it is at the height of the radiation source, the rotational measurement more easily identifies the direction where the radiation intensity is lowest, that is, the side opposite the radiation source.

[0060] Furthermore, by precisely adjusting the vertical position of the gamma dose rate meter 100, the radiation intensity received during measurement can be ensured to be closer to the true value. This helps reduce errors caused by improper measurement position and improves the accuracy of subsequent estimates of the target radiation source distance and activity value. Furthermore, the presence of the lifting structure allows for continuous measurement at multiple heights, thereby obtaining more comprehensive radiation intensity distribution information and providing richer data support for radiation source analysis and assessment.

[0061] Furthermore, the source may be located in a variety of environments and scenarios, such as on the ground, on rooftops, or on elevated platforms. Traditional fixed-height measurement methods may not be adaptable to these complex scenarios. However, the bracket 200 with a lifting mechanism allows the gamma dose rate meter 100 to be flexibly adjusted according to the actual scenario, enabling accurate measurement of radiation intensity at various heights. This flexibility enables this technical solution to perform effectively in a wider range of application scenarios.

[0062] In some embodiments of the present application, the calculation formula used to estimate the distance value of the target radiation source based on the first measurement value, the second measurement value and the preset distance value includes: Wherein d1 is the estimated distance value of the target radiation source, d is the preset distance value, D1 is the first measurement value, and D2 is the second measurement value.

[0063] like Figure 3 As shown, assuming that the target radiation source is a γ source that is approximately a point source and there is no obstruction in the irradiation direction of the γ source, if the distance between the measurement point M1 and the measurement point M2, as well as the γ radiation air absorption dose rate measured at these two points, is known, the distance estimation formula can be used Estimate d1. In the present application, the gamma dose rate meter 100 can rotate horizontally. The measurement point M1 corresponds to the position where the radiation dose rate measured by the gamma dose rate meter 100 is minimum, and the measurement point M2 corresponds to the position where the radiation dose rate measured by the gamma dose rate meter 100 is maximum (or the position on the opposite side of the position where the radiation dose rate measured by the gamma dose rate meter 100 is minimum, i.e., the position after rotating 180°). The distance between the measurement points M1 and M2 is related to the rotation radius of the gamma dose rate meter 100 and is a fixed value that can be set in advance.

[0064] In some embodiments of the present application, the calculation formula used to estimate the activity value of the target radiation source based on the air absorption dose rate background value, the second measurement value, and the estimated distance value of the target radiation source includes: Where A is the estimated activity value of the target radiation source, D0 is the background value of the air absorption dose rate (the gamma radiation air absorption dose rate measured in the same environmental area not affected by the target radiation source), Γ δ is the air kerma rate constant.

[0065] The above embodiment estimates the approximate distance of the target radiation source, combines the background value of the air absorption dose rate and the preset activity estimation formula The activity value of the target radiation source can be further estimated. It should be noted that different gamma nuclides have different air kerma rate constants, so when estimating the activity value of the target radiation source, it is necessary to make corresponding estimates based on the type of target radiation source.

[0066] It will be apparent to those skilled in the art that the present application is not limited to the details of the exemplary embodiments described above and that the present application can be implemented in other specific forms without departing from the spirit or essential characteristics of the present application. Therefore, the embodiments should be considered in all respects as illustrative and non-restrictive, and the scope of the present application is defined by the appended claims, not the foregoing description, and all variations within the meaning and range of equivalents of the claims are intended to be included therein. Any reference sign in a claim should not be construed as limiting the claim to which it relates.

Claims

1. A device for locating a gamma radiation source, characterized in that: include: Gamma dose rate meter, used to measure the gamma radiation air absorption dose rate; a bracket, used for supporting and moving the gamma dose rate meter, so that the gamma dose rate meter can be rotated in the horizontal direction; A shielding plate is mounted on a bracket and can rotate coaxially with the gamma dose rate meter to continuously shield radiation from the rear side of the gamma dose rate meter; The control module is used to obtain measurement data from the gamma dose rate meter and control the rotation angle of the bracket.

2. The device according to claim 1, characterized in that The bracket is also provided with a laser emitter parallel to the gamma dose rate meter, for indicating the direction of the target radiation source.

3. The device according to claim 1, characterized in that The bracket includes a lifting structure, so that when the bracket is lifted or lowered by the lifting structure, the gamma dose rate meter can be driven to be lifted or lowered in a vertical direction.

4. The device according to claim 1, characterized in that The control module is also used to collect meteorological parameters, geographical location information and the rotation angle of the bracket.

5. A method for locating a gamma radiation source, characterized in that: The method for locating a gamma radiation source according to any one of claims 1 to 4 comprises: Outside the target radiation field, use a gamma dose rate meter to measure and record the background value of air absorbed dose rate; Placing a device for locating a gamma radiation source in a target radiation field, rotating the gamma dose rate meter one circle to determine a direction in which the gamma radiation air absorption dose rate is minimized, with the opposite side of the direction being recorded as the direction of the target radiation source, and measuring the gamma radiation air absorption dose rate in the direction and on the opposite side, respectively, and recording them as a first measurement value and a second measurement value, respectively; estimating a distance value of the target radiation source based on the first measurement value, the second measurement value, and a preset distance value, wherein the preset distance value is a value determined according to a rotation range of the gamma dose rate meter; and The activity value of the target radiation source is estimated according to the background value of the air absorbed dose rate, the second measurement value and the estimated distance value of the target radiation source.

6. The method according to claim 5, characterized in that The method also includes sending detection information of the target radiation source to a designated terminal device, where the detection information includes the direction of the target radiation source and the estimated distance value and activity value of the target radiation source.

7. The method according to claim 5, characterized in that The bracket includes a lifting structure, so that when the bracket is lifted or lowered by the lifting structure, the gamma dose rate meter can be driven to be lifted or lowered in the vertical direction; Before the step of rotating the gamma dose rate meter for one circle to determine the orientation at which the gamma radiation air absorption dose rate is minimum, the method further includes: fixing the rotation angle of the gamma dose rate meter and adjusting its vertical position by a lifting structure until the height corresponding to the maximum value of the gamma radiation air absorption dose rate is reached.

8. The method according to any one of claims 5 to 7, characterized in that The calculation formula used to estimate the distance value of the target radiation source based on the first measurement value, the second measurement value and the preset distance value includes: Wherein d1 is the estimated distance value of the target radiation source, d is the preset distance value, D1 is the first measurement value, and D2 is the second measurement value.

9. The method according to claim 8, characterized in that The calculation formula used to estimate the activity value of the target radiation source based on the air absorption dose rate background value, the second measurement value, and the estimated distance value of the target radiation source includes: Where A is the estimated activity value of the target radiation source, D0 is the background value of the air absorption dose rate, Γ δ is the air kerma rate constant.

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