Chamfered cube-shaped neutron spectrum measuring device and neutron spectrum measuring method

Abstract

The invention discloses a chamfer cube-shaped neutron spectrum measurement device and a neutron spectrum measurement method. The neutron spectrum measurement device comprises a main body moderation body, an insertion assembly and a neutron detector, the main body moderation body is in a chamfered cube shape, the outer surface of the main body moderation body comprises twelve congruent flattened hexagonal surfaces and six congruent square surfaces, and first grooves are formed in the six congruent square surfaces; the insertion assembly is fixed in the first groove, and N neutron detectors are arranged on the insertion assembly; the N neutron detectors on each insertion assembly are located on the coordinate axis of the same Cartesian coordinate system, and the distances between the neutron detectors with the same sequence on each insertion assembly and the origin of coordinates of the Cartesian coordinate system are consistent. According to the scheme, high-precision measurement of the neutron energy spectrum in a wide energy range is facilitated, compactness and standardization of the device structure are also considered, and the problem that high precision, a wide energy region and portability are difficult to consider in the prior art can be effectively solved.

Description

Technical Field

[0001] This invention relates to the field of neutron spectrum measurement technology, and more specifically, to a chamfered cubic neutron spectrum measurement device and method. Background Technology

[0002] Neutron spectroscopy measurements have significant applications in nuclear physics, radiation protection, nuclear reactor monitoring, space radiation detection, and medicine. Accurate neutron spectrum measurements are crucial for understanding neutron-matter interactions, assessing radiation dose, ensuring radiation safety, and optimizing the operational performance of nuclear facilities. However, existing neutron spectroscopy detection technologies still face numerous challenges in practical applications. On the one hand, traditional neutron spectroscopy instruments are typically bulky and heavy, making them unsuitable for portable on-site measurements. On the other hand, achieving high sensitivity and high resolution neutron energy spectrum measurements over an extremely wide energy range (e.g., 1E-9 to 1E2 MeV) has been a persistent challenge. Therefore, providing a neutron spectroscopy measurement scheme that achieves high precision, portability, and good anisotropic response consistency over a wide energy range is a key issue that urgently needs to be addressed in current neutron energy spectrum measurement technology. Summary of the Invention

[0003] In order to solve at least one of the technical problems in the background art, the present invention proposes a chamfered cubic neutron spectrum measurement device and a neutron spectrum measurement method.

[0004] According to one aspect of the present invention, a chamfered cubic neutron spectrum measuring device is provided, the device comprising: a main moderator, an insertion component, and a neutron detector;

[0005] The main moderating body is in the shape of a chamfered cube, and its outer surface includes twelve congruent flattened hexagonal faces and six congruent square faces. Each of the six congruent square faces has a first groove.

[0006] The insertion component is fixed in the first groove, and N neutron detectors are provided on the insertion component; the N neutron detectors on each insertion component are all located on the coordinate axes of the same Cartesian coordinate system, and the neutron detectors of the same order on each insertion component are at the same distance from the origin of the Cartesian coordinate system.

[0007] Optionally, each of the twelve congruent flattened hexagonal surfaces has a second groove; the device further includes: an embedded component, which is disposed at the opening of the second groove and fixedly connected to the second groove.

[0008] Optionally, the chamfered cubic neutron spectrum measuring device further includes a sealing assembly for fixing the insertion assembly, wherein the sealing assembly covers the opening of the first groove and is fixedly connected to the first groove.

[0009] Optionally, the origin of the Cartesian coordinate system is located at the geometric center of the chamfered cube-shaped neutron spectrum measuring device, and the centers of the six congruent square faces are all located on the coordinate axes of the Cartesian coordinate system.

[0010] Optionally, the N neutron detectors are arranged at equal intervals.

[0011] Optionally, the material of the main moderating body is a metal hydride or polyethylene.

[0012] Optionally, the neutron detector uses a lithium-containing scintillator as the thermal neutron-sensitive material.

[0013] Optionally, the sealing assembly uses an electrical conductivity greater than 2.0 × 10⁻⁶. 7 Materials with S / m.

[0014] According to another aspect of the present invention, a method for determining a response function is also provided, for determining the response function corresponding to the above-described chamfered cubic neutron spectrum measuring device, the method comprising:

[0015] The target energy range is divided into multiple energy groups, and the chamfered cube-shaped neutron spectrum measuring device is placed in the environment corresponding to each energy group for detection to obtain the count rate data of each neutron detector.

[0016] For each type of detector in the N types of detectors, the response data of the detector in that type of detector is determined based on the count rate data of each neutron detector in that type of detector. In this case, neutron detectors that are equidistant from the origin of the Cartesian coordinate system are classified into one type, thus obtaining the N types of detectors.

[0017] Based on the response data of the N-type detectors corresponding to each energy group, a response function of the chamfered cubic neutron spectrum measuring device corresponding to the target energy range is generated.

[0018] According to another aspect of the present invention, a neutron spectrum measurement method is also provided, applied to the above-described chamfered cubic neutron spectrum measurement apparatus, the method comprising:

[0019] Acquire the count rate data detected by each of the neutron detectors in the chamfered cube-shaped neutron spectrum measuring device;

[0020] For each type of detector in the N types of detectors, the response data of the detector in that type of detector is determined based on the count rate data of each neutron detector in that type of detector. In this case, neutron detectors that are equidistant from the origin of the Cartesian coordinate system are classified into one type, thus obtaining the N types of detectors.

[0021] The neutron energy spectrum measurement results are determined based on the response data of the N-type detector and the response function corresponding to the chamfered cube-shaped neutron spectrum measurement device.

[0022] The beneficial effects of this invention are as follows:

[0023] This invention employs a main moderating body with an outer surface comprising twelve congruent flattened hexagonal surfaces and six congruent square surfaces. Insertion components are positioned at the centers of the six congruent square surfaces. Multiple neutron detectors are arranged along the same Cartesian coordinate axis on each insertion component, with the neutron detectors of the same order on each component equidistant from the origin of the Cartesian coordinate system. This structural design allows for a regular spatial distribution and grouping of neutron detectors, thereby improving the consistency of the device's response to neutrons from different directions and facilitating subsequent signal processing and energy spectrum reconstruction based on spatial grouping. This approach not only contributes to high-precision measurement of the neutron energy spectrum over a wide energy range but also ensures the compactness and standardization of the device structure, providing a technical foundation for portable applications and field deployment of neutron spectrum measurement. It effectively overcomes the difficulty of simultaneously achieving high precision, a wide energy range, and portability in existing technologies. Attached Figure Description

[0024] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort. In the drawings:

[0025] Figure 1 This is a geometric schematic diagram of the components of the chamfered cubic neutron spectrum measuring device according to an embodiment of the present invention;

[0026] Figure 2 This is a schematic diagram of the external appearance of the chamfered cubic neutron spectrum measuring device according to an embodiment of the present invention;

[0027] Figure 3 This is the neutron response function of the exemplary device of the present invention;

[0028] Figure 4 These are neutron spectrum measurement results from an exemplary device of the present invention;

[0029] Figure 5 This is an exemplary device of the present invention for the slowing down of polyethylene. 252 Measurement results from the Cf neutron source;

[0030] Figure 6 This is a flowchart of the response function determination method according to an embodiment of the present invention;

[0031] Figure 7 This is a flowchart of the sub-spectrum measurement method in an embodiment of the present invention. Detailed Implementation

[0032] To enable those skilled in the art to better understand the present invention, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort should fall within the scope of protection of the present invention.

[0033] Those skilled in the art will understand that embodiments of the present invention can be provided as methods, systems, or computer program products. Therefore, the present invention can take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, the present invention can take the form of a computer program product embodied on one or more computer-usable storage media (including, but not limited to, disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0034] It should be noted that the terms "comprising" and "having" and any variations thereof in the specification, claims and accompanying drawings of this invention are intended to cover non-exclusive inclusion. For example, a process, method, system, product or device that includes a series of steps or units is not necessarily limited to those steps or units that are explicitly listed, but may include other steps or units that are not explicitly listed or that are inherent to such processes, methods, products or devices.

[0035] It should be noted that, unless otherwise specified, the embodiments and features described in the present invention can be combined with each other. The present invention will now be described in detail with reference to the accompanying drawings and embodiments.

[0036] like Figure 1 As shown, in one embodiment of the present invention, the chamfered cubic neutron spectrum measurement device of the present invention includes: a main slowing body 1, an insertion component 3, and a neutron detector 4.

[0037] The main moderating body 1 is in the shape of a chamfered cube, and its outer surface includes twelve congruent flattened hexagonal faces and six congruent square faces, each of which has a first groove.

[0038] The insertion component 3 is fixed within the first groove, and N neutron detectors 4 are disposed on the insertion component 3. All N neutron detectors 4 on each insertion component 3 are located on the same coordinate axis of a Cartesian coordinate system, and the neutron detectors 4 of the same order on each insertion component 3 are equidistant from the origin of the Cartesian coordinate system.

[0039] In one embodiment of the present invention, a first groove is provided on each square surface, and an insertion component 3 is provided in each first groove, that is, there are six insertion components 3.

[0040] In one embodiment of the present invention, the value of N ranges from 3 to 16.

[0041] In one embodiment of the present invention, the main moderating body 1 is a chamfered cube shape. This structure consists of twelve congruent flattened hexagonal faces and six congruent square faces. Each square face has four edges adjacent to four different hexagonal faces, and each hexagonal face is simultaneously adjacent to two square faces. This structure exhibits high spatial symmetry. The chamfered cube can be understood as a conventional cube with each edge chamfered, i.e., adding a flattened hexagonal face to each of the twelve edges of the original cube, making all six faces of the original cube squares, with each square face adjacent to a hexagonal face on all four sides. The overall structure ensures mechanical stability and provides a spatial basis for the uniform arrangement of internal components. Furthermore, the chamfered cube structure facilitates the isotropic and uniform slowing of neutrons and the symmetrical arrangement of detectors, thereby improving the response consistency and accuracy of neutron spectrum measurements.

[0042] Because the main modulator 1 of this invention adopts a chamfered cubic shape, the orthogonal axis of symmetry defining the detector distribution is the center of the face of the main modulator 1, rather than the vertex of the modulator as the symmetry point in some prior art solutions. This improvement makes the surface integral distribution of the main modulator more uniform, with alternating hexagonal and square faces, effectively reducing abrupt changes in local curvature and making the volume distribution closer to the isotropic nature of a sphere, thereby significantly improving the isotropic response consistency of this device.

[0043] Furthermore, of the 18 faces of the main modulator 1 in the chamfered cubic structure of this invention, 12 are hexagonal faces. These 12 hexagonal faces can be used to add reinforcing modulators (such as embedding high atomic number materials), thus giving the device of this invention greater scalability in terms of the upper limit of its energy response range. In addition, the chamfered cubic structure, with its alternating distribution of hexagonal and square faces, achieves a more uniform stress distribution, making it more suitable for manufacturing with high-strength materials such as metals and resins. This effectively reduces the risk of structural deformation and improves the overall mechanical stability of the device.

[0044] In one embodiment of the present invention, the first groove may specifically be a square groove.

[0045] In this invention, the arrangement of the neutron detectors 4 exhibits a high degree of spatial regularity and group correspondence. Specifically, six insertion components 3 are respectively installed at the center of the six square faces of the chamfered cube, and N neutron detectors 4 are arranged along one coordinate axis of the corresponding Cartesian coordinate system in each insertion component 3. That is, the six insertion components 3 correspond to the positive x-axis, negative x-axis, positive y-axis, negative y-axis, positive z-axis, and negative z-axis, respectively. The N neutron detectors 4 on each insertion component 3 are arranged sequentially along their respective coordinate axes, and the distance of the first detector on each insertion component from the origin is the same, the distance of the second detector on each insertion component from the origin is also the same, and so on, up to the Nth detector. This arrangement allows detectors equidistant from the origin to be grouped together, with detectors within each group located in different positive and negative coordinate axes, resulting in a symmetrical spatial distribution and clear grouping relationships.

[0046] For example, assuming each insertion component has three neutron detectors (4), they are divided into three groups. The first group consists of six detectors closest to the origin, located in the positive and negative directions of the x, y, and z coordinate axes, all at a distance of d1 from the origin. The second group consists of six detectors at a distance of d2 from the origin, also distributed in the six directions. The third group consists of six detectors at a distance of d3 from the origin. This structural design not only achieves uniform coverage of the measurement space but also facilitates the subsequent classification and analysis of response data from different distance groups, thereby improving the accuracy of neutron spectrum reconstruction and the consistency of spatial response.

[0047] The device of this invention features grooves at the centers of the six square faces of the main modulator body, which is a chamfered cubic structure. Insertion components are installed within each groove, and multiple neutron detectors are arranged along the same Cartesian coordinate axis on each insertion component. The detectors of the same order on each insertion component maintain a consistent distance from the origin. This design not only achieves a regular distribution and grouping of detectors in three-dimensional space, significantly improving the consistency of the device's response to neutrons from different directions, but also facilitates grouped processing of measurement data, improving the accuracy of neutron energy spectrum reconstruction. Furthermore, the compact and orderly chamfered cubic structure contributes to the miniaturization and modularization of the device, meeting the needs of portable field measurements and multi-scenario applications.

[0048] In one embodiment of the present invention, each of the twelve congruent flattened hexagonal surfaces has a second groove; the device further includes: an embedded component 2, which is disposed at the opening of the second groove and is fixedly connected to the second groove.

[0049] In one embodiment of the present invention, the second groove may specifically be a cylindrical groove.

[0050] In this invention, the embedded component 2 is typically made of high-density metal or specific functional materials, which can further adjust or optimize the device's moderation, shielding, and response characteristics to neutrons in different energy ranges. By distributing the embedded component 2 in a hexagonal pattern, not only can the overall mechanical stability and spatial uniformity of the device be enhanced, but the neutron response in each direction can also be finely adjusted, making the measurement results more accurate and consistent in all directions, effectively improving the device's measurement performance and applicability.

[0051] In one embodiment of the present invention, the chamfered cubic neutron spectrum measuring device further includes: a sealing component 5 for fixing the insertion component 3, the sealing component 5 covering the opening of the first groove and fixedly connected to the first groove.

[0052] In this invention, the purpose of the sealing component 5 is to effectively fix and position the insertion component. By covering the opening of the first groove with the sealing component 5 and fixing it to the groove, loosening or displacement of the insertion component 3 can be prevented during the use and transportation of the device, thereby ensuring the spatial accuracy of the neutron detector 4 arrangement and the stability of the measurement. In addition, the sealing component 5 also plays a sealing and protective role, effectively blocking the adverse effects of dust, moisture, and other external environmental factors on the internal components of the device, extending the service life of the device, and ensuring the long-term reliability of the device operation and the accuracy of data acquisition.

[0053] In one embodiment of the present invention, the origin of the Cartesian coordinate system is located at the geometric center of the chamfered cube-shaped neutron spectrum measuring device, and the centers of the six congruent square faces are all located on the coordinate axes of the Cartesian coordinate system.

[0054] In one embodiment of the present invention, N neutron detectors are arranged sequentially along the coordinate axis of the insertion component, and the distance between any two adjacent neutron detectors is equal, i.e., the N neutron detectors are equally spaced. The advantage of this equal-spaced arrangement is that it allows for a more uniform spatial coverage by each detector, effectively avoiding overly dense or sparse responses in any region, and improving the overall spatial sampling uniformity and response consistency of the device. Simultaneously, the equidistant distribution facilitates subsequent unified processing and grouping of detector measurement data, helping to simplify the data analysis process, improve the accuracy and efficiency of energy spectrum reconstruction, and thus further enhance the reliability of neutron spectrum measurement results.

[0055] In one embodiment of the present invention, the material of the main moderating body 1 is a metal hydride or polyethylene, including but not limited to aluminum hydride, magnesium-based metal hydride, titanium-based metal hydride, and having a density greater than 0.94 g / cm³. 3 High-density polyethylene, etc.

[0056] In one embodiment of the present invention, the material of the insertion component 3 is the same as the material of the main modulator 1.

[0057] In one embodiment of the present invention, the embedded component 2 is made of a metallic material, including but not limited to lead, tungsten, copper, iron, etc., with a purity greater than 99%.

[0058] In one embodiment of the present invention, the neutron detector 4 uses a lithium-containing scintillator as the thermal neutron-sensitive material, including but not limited to lithium glass scintillators, LiI (Eu), Cs2LiYCl6:Ce (CLYC), Cs2LiLaBr6:Ce (CLLB), and Cs2LiLaBr6-xClx:Ce (CLLBC). The neutron detector 4 has 18 to 72 scintillators.

[0059] In one embodiment of the present invention, the sealing component 5 adopts an electrical conductivity greater than 2.0 × 10⁻⁶. 7 Materials for S / m include copper, copper alloys, aluminum, and aluminum alloys.

[0060] In one embodiment of the present invention, the chamfered cubic neutron spectrum measuring device is assembled from a main modulator 1, an embedded component 2, an insertion component 3, a neutron detector 4, and a sealing component 5. After assembly, the neutron spectrum measuring device is in the shape of a chamfered cube. Optionally, the original cube has a side length of 20-40 cm and a chamfer radius of 2-8 cm. The chamfered cubic neutron spectrum measuring device of the present invention has eighteen faces, and the outer surface includes twelve congruent flattened hexagonal faces and six congruent square faces. The neutron detector 4 is arranged within the chamfered cubic neutron spectrum measuring device along three mutually orthogonal coordinate axes (x-axis, y-axis, z-axis) of the Cartesian coordinate system. The origin O of the Cartesian coordinate system is located at the geometric center O of the chamfered cubic neutron spectrum measuring device, and the centers of the six congruent square faces of the chamfered cubic neutron spectrum measuring device are all on the three coordinate axes (x-axis, y-axis, z-axis).

[0061] In one embodiment of the present invention, cylindrical grooves with a diameter of 4 to 15 cm and a depth of 2 to 4 cm are formed on each of the twelve congruent flattened hexagonal surfaces, and the embedded component 2 is fixed to the opening of the cylindrical groove by bolts.

[0062] In one embodiment of the present invention, square grooves with a side length of 3 to 6 cm are opened on each of the six congruent square surfaces. The insertion component 3 is first fixed by the sealing component 5, and then the sealing component 5 is fixed by bolts.

[0063] In one embodiment of the present invention, the embedded component 2 can be fixed in the cylindrical groove on the hexagonal surface of the main modulator 1 by bolts, and there are 12 embedded components 2 in total.

[0064] In one embodiment of the present invention, the insertion component 3 has an inner groove, and 8 to 12 neutron detectors 4 are equidistantly arranged in the insertion component 3 along the longitudinal centroidal axis of the insertion component 3 with a spacing of 5 to 12 mm. There are a total of 6 insertion components 3.

[0065] like Figure 1 and Figure 2 As shown, the exemplary chamfered cubic neutron spectrum measuring device of the present invention is assembled from five components: a main modulator 1, an embedded component 2, an insertion component 3, a neutron detector 4, and a sealing component 5. The main modulator 1 is made of high-density polyethylene (e.g., HDPE 5000S) with a density of 0.95 g / cm³. 3 The main modulator 1 consists of one unit with a mass of 1.18 kg. The embedded component 2 is made of lead (e.g., Pb 99.994) with a density of 11.34 g / cm³. 3 There are 12 embedded components 2, and the total weight of the 12 embedded components 2 is 7.35 kg. The insert component 3 is made of high-density polyethylene (e.g., HDPE 5000S) with a density of 0.95 g / cm³.3 There are 6 insertion components 3, with a total mass of 0.59 kg. The neutron detector 4 consists of 4×4×4 mm lithium-ion glass (e.g., GS20) coupled to SiPM (e.g., JSP-TP3050-SMT), and includes temperature control, power supply, and data analysis and acquisition circuitry. There are 60 neutron detectors 4, with a total mass of 1.5 kg. The sealing component 5 is made of aluminum alloy (e.g., A93003) with a density of 2.73 g / cm³. 3 There are 6 sealing components 5, and the total weight of the 6 sealing components 5 is 1.28 kg.

[0066] like Figure 1 and Figure 2 As shown, in a specific embodiment of the present invention, cylindrical grooves and steps are formed at the center of each of the twelve hexagonal faces of the main modulating body 1. An embedded component 2 is inserted into these cylindrical grooves and fixed with bolts. Square grooves are formed at the center of each of the six congruent square faces of the main modulating body 1. Insertion components 4 are inserted into these square grooves and fixed with sealing components 5, which are then fixed with bolts. Ten neutron detectors 4 are equidistantly arranged along the longitudinal centroidal axis of each insertion component 3, with a spacing of 8 mm. After assembly, the 60 neutron detectors 4 are arranged along three coordinate axes (x-axis, y-axis, z-axis), with the origin of the Cartesian coordinate system located at the geometric center O of the main modulating body 1, and the centers of the six congruent square faces of the main modulating body 1 all lying on the three coordinate axes (x-axis, y-axis, z-axis). The total mass of the exemplary device of the present invention is 11.9 kg, and the total volume is 3934 cm³. 3 The distance between two parallel congruent square faces is 16cm, and the distance between two parallel congruent flattened hexagonal faces is 18cm. The 18×18×16cm space can accommodate the exemplary device of the present invention.

[0067] To evaluate the angular response deviation of the exemplary device of the present invention, in addition to the exemplary device of the present invention, a control octahedral device was set up. The moderator body 1 of the exemplary device of the present invention was replaced with an octahedral moderator having the same material and an outer sphere, while the other components remained unchanged, serving as a comparison object. Using the X-axis as the rotation axis, both the chamfered cubic neutron spectrum measuring device of the present invention and the control octahedral device have four-fold rotational symmetry. Therefore, for examining the angular difference in neutron response, two angles differing by 45° were selected. Using the Z-axis as the reference incident direction, the neutrons were incident on the exemplary device or the octahedral device of the present invention at 0° and 45° respectively. The angular response deviation Di of the i-th type of detector is defined as follows:

[0068]

[0069] It is the response of the i-th type detector to the j-th energy group neutron incident at 0°. The response of the i-th type detector to the j-th energy group neutron incident at 45° is divided into 110 energy groups in the energy range of 1E-9 to 1E2 MeV, yielding Di, as shown below. Figure 4 As shown, the exemplary device of the present invention has a smaller angular response deviation, with an average angular response deviation of 5% and a maximum of 13% for the 10 types of detectors, while the octahedral device has an average angular response deviation of 13% and a maximum angular response deviation of 38% for the 10 types of detectors. Therefore, compared with the octahedral device, the device of the present invention has a better isotropic response.

[0070] The exemplary device of the present invention is used to measure polyethylene after slowing down. 252 Based on the Cf energy spectrum and following the data processing method for the neutron response of the neutron detector, the Cf energy values ​​of M1, M2, M3, M4, M5, M6, M7, M8, M9, and M10 are 1.5E-3, 1.7E-3, 1.9E-3, 2.0E-3, 2.2E-3, 2.4E-3, 2.2E-3, 2.5E-3, 2.2E-3, and 2.5E-3, respectively. Figure 3 The response function was analyzed using the maximum entropy method to obtain the energy spectrum, as shown below. Figure 5 As shown. The results indicate that the exemplary device of the present invention moderates polyethylene. 252 The Cf energy spectrum measurement results are basically consistent with the actual situation, and the measurement accuracy of the device of the present invention is good.

[0071] According to another aspect of the present invention, a method for determining a response function is also provided, for determining the response function corresponding to the above-described chamfered cubic neutron spectrum measuring device. For example... Figure 6 As shown, in one embodiment of the present invention, the method includes steps S101 to S103.

[0072] Step S101: Divide the target energy range into multiple energy groups, and place the chamfered cube-shaped neutron spectrum measuring device in the environment corresponding to each energy group for detection, thereby obtaining the count rate data of each neutron detector.

[0073] This step, through energy group partitioning and group-by-group detection, enables the comprehensive acquisition of neutron detector response data in different energy regions, providing a fundamental data guarantee for the subsequent construction of response functions.

[0074] Step S102: For each type of detector in the N types of detectors, determine the response data of the detector in that type of detector based on the count rate data of each neutron detector in that type of detector. In this step, neutron detectors that are equidistant from the origin of the Cartesian coordinate system are grouped into one type, thus obtaining the N types of detectors.

[0075] This invention groups neutron detectors equidistant from the origin of the Cartesian coordinate system into the same category, and calculates the response data for each category based on its count rate data. This fully utilizes the advantages of the invention's symmetrical spatial structure and clearly defined detector grouping. Grouping detectors with the same distance from the origin facilitates the summarization and organization of response information, reduces random errors from individual detectors, and improves the stability of data analysis.

[0076] Step S103: Based on the response data of the N-type detectors corresponding to each energy group, generate the response function of the chamfered cube-shaped neutron spectrum measuring device corresponding to the target energy range.

[0077] This invention generates a response function based on the grouped response data of each energy group, enabling the measuring device to accurately reflect the energy spectrum distribution and providing reliable support for subsequent energy spectrum calculation.

[0078] In one embodiment of the present invention, the step S102 above, which involves determining the response data of the detector based on the count rate data of each neutron detector in the detector type, specifically includes:

[0079] The count rate data of the two neutron detectors located on the x-axis, the two neutron detectors located on the y-axis, and the two neutron detectors located on the z-axis are summed. Then, the sums of the three coordinate axes are squared and the square root is taken to obtain the response data of this type of detector.

[0080] In one embodiment of the present invention, six neutron detectors 4 at the same distance from the geometric center O (origin of the Cartesian coordinate system) of the main slowing body 1 are considered as one type of detector, resulting in a total of N types of detectors. The response data calculation steps for each type of detector are as follows: The six neutron detectors 4 of the same type are located on three mutually orthogonal axes (x, y, z). The count rates of the two neutron detectors 4 located on the x-axis are summed, the count rates of the two neutron detectors 4 located on the y-axis are summed, and the count rates of the two neutron detectors 4 located on the z-axis are summed. Then, the summation results of the three axes are squared and the square root is taken to obtain the response data of that type of detector. This process is repeated sequentially to obtain the response data of N types of detectors, thereby determining the response function of the device.

[0081] by Figure 1Taking the exemplary device as an example, this invention uses six neutron detectors at the same distance from the geometric center O of the main modulating body 1 as one type of detector, resulting in a total of 10 types of detectors. The first type of detectors are 4.x1, 4.x-1, 4.y1, 4.y-1, 4.z1, and 4.z-1. The response data calculation steps for each type of detector are as follows: the count rates of the two neutron detectors 4, 4.x1, and 4.x-1 located on the x-axis are summed; the count rates of the two neutron detectors 4, 4.y1, and 4.y-1 located on the y-axis are summed; and the count rates of the two neutron detectors 4, 4.y1, and 4.y-1 located on the z-axis are summed. Then, the summation results of the three axes are squared, and the square root is taken to obtain the response data M1 of that type of detector. The energy groups M2, M3, M4, M5, M6, M7, M8, M9, and M10 are processed sequentially to obtain the response function or as input to the spectral decomposition algorithm. Within the energy range of 1E-9 to 1E2 MeV, the energy is divided into 110 energy groups. The response data of this exemplary device to each energy group is calculated, thereby obtaining the response function of the exemplary device of this invention. The response function is as follows: Figure 3 As shown.

[0082] According to another aspect of the present invention, a neutron spectrum measurement method is also provided, applied to the aforementioned chamfered cubic neutron spectrum measurement device. For example... Figure 7 As shown, in one embodiment of the present invention, the method includes steps S201 to S203.

[0083] Step S201: Obtain the count rate data detected by each neutron detector in the chamfered cube-shaped neutron spectrum measuring device.

[0084] Step S202: For each type of detector in the N types of detectors, determine the response data of the detector in that type of detector based on the count rate data of each neutron detector in that type of detector. In this step, neutron detectors that are equidistant from the origin of the Cartesian coordinate system are grouped into one type, thus obtaining the N types of detectors.

[0085] Step S203: Determine the neutron energy spectrum measurement result based on the response data of the N-type detector and the response function corresponding to the chamfered cube-shaped neutron spectrum measurement device.

[0086] This invention, after obtaining the response function of a chamfered cubic neutron spectrum measuring device, allows for direct energy spectrum measurement of actual neutron fields based on this response function. Specifically, firstly, count rate data under the neutron field to be measured is acquired through various detectors in the device; then, this count rate data is combined with a pre-calibrated response function, and mathematical methods such as energy spectrum expansion are used to establish a relationship model between the count rate and the neutron energy spectrum. By solving this model, the actual neutron energy spectrum distribution is deduced. In this way, the user only needs to measure the response of each detector once, and then combine it with the response function to accurately obtain the energy spectrum result of the neutron field to be measured, achieving efficient and practical neutron energy spectrum measurement.

[0087] In one embodiment of the present invention, in step S203, the actual measurement data can be inverted and analyzed using a spectrum resolution algorithm based on the response data of the N-type detectors and the response function corresponding to the chamfered cubic neutron spectrum measuring device. Specifically, the grouped response data and the pre-calibrated response function are first used to construct a set of mathematical equations. Then, common spectrum resolution algorithms (such as least squares, SAND-II, MAXED, etc.) are used to solve for the neutron spectrum distribution under each energy group. The spectrum resolution algorithm can effectively process finite response data, and by combining physical constraints and prior information, accurately reconstruct the neutron spectrum, thereby obtaining the final neutron spectrum measurement result.

[0088] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A chamfered cubic neutron spectrum measuring device, characterized in that, include: The main modulator, the insertion assembly, and the neutron detector; The main moderating body is in the shape of a chamfered cube, and its outer surface includes twelve congruent flattened hexagonal faces and six congruent square faces. Each of the six congruent square faces has a first groove. The insertion component is fixed in the first groove, and N neutron detectors are provided on the insertion component; the N neutron detectors on each insertion component are all located on the coordinate axes of the same Cartesian coordinate system, and the neutron detectors of the same order on each insertion component are at the same distance from the origin of the Cartesian coordinate system.

2. The chamfered cubic neutron spectrum measuring device according to claim 1, characterized in that, Each of the twelve congruent, flattened hexagonal surfaces has a second groove. The device further includes an embedded component, which is disposed at the opening of the second groove and is fixedly connected to the second groove.

3. The chamfered cubic neutron spectrum measuring device according to claim 1, characterized in that, Also includes: A sealing assembly is used to fix the insertion assembly. The sealing assembly covers the opening of the first groove and is fixedly connected to the first groove.

4. The chamfered cubic neutron spectrum measuring device according to claim 1, characterized in that, The origin of the Cartesian coordinate system is located at the geometric center of the chamfered cube-shaped neutron spectrum measuring device, and the centers of the six congruent square faces are all located on the coordinate axes of the Cartesian coordinate system.

5. The chamfered cubic neutron spectrum measuring device according to claim 4, characterized in that, The N neutron detectors are arranged at equal intervals.

6. The chamfered cubic neutron spectrum measuring device according to claim 1, characterized in that, The material of the main modulator is a metal hydride or polyethylene.

7. The chamfered cubic neutron spectrum measuring device according to claim 1, characterized in that, The neutron detector uses a lithium-containing scintillator as the thermal neutron-sensitive material.

8. The chamfered cubic neutron spectrum measuring device according to claim 3, characterized in that, The sealing assembly uses an electrical conductivity greater than 2.0 × 10⁻⁶. 7 Materials with S / m.

9. A method for determining a response function, characterized in that, The method for determining the response function corresponding to the neutron spectrum measuring device with a chamfered cubic shape as described in any one of claims 1 to 8 includes: The target energy range is divided into multiple energy groups, and the chamfered cube-shaped neutron spectrum measuring device is placed in the environment corresponding to each energy group for detection to obtain the count rate data of each neutron detector. For each type of detector in the N types of detectors, the response data of the detector in that type of detector is determined based on the count rate data of each neutron detector in that type of detector. In this case, neutron detectors that are equidistant from the origin of the Cartesian coordinate system are classified into one type, thus obtaining the N types of detectors. Based on the response data of the N-type detectors corresponding to each energy group, a response function of the chamfered cubic neutron spectrum measuring device corresponding to the target energy range is generated.

10. A method for measuring neutron spectra, characterized in that, The method, applied to the chamfered cubic neutron spectrum measuring apparatus according to any one of claims 1 to 8, comprises: Acquire the count rate data detected by each of the neutron detectors in the chamfered cube-shaped neutron spectrum measuring device; For each type of detector in the N types of detectors, the response data of the detector in that type of detector is determined based on the count rate data of each neutron detector in that type of detector. In this case, neutron detectors that are equidistant from the origin of the Cartesian coordinate system are classified into one type, thus obtaining the N types of detectors. The neutron energy spectrum measurement results are determined based on the response data of the N-type detector and the response function corresponding to the chamfered cube-shaped neutron spectrum measurement device.

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