Energy spectrum measurement device and method for tough-induced radiation X-rays
By introducing multi-layer absorption measurement components and processor design into the detector, the problem that existing detectors cannot measure high-energy tough radiation-induced X-ray energy spectrum is solved, and effective measurement of MeV-level continuous spectrum X-rays is achieved.
Patent Information
- Application Number
- CN202510185561.1
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-02-19
- Publication Date
- 2025-04-25
AI Technical Summary
Existing detectors cannot directly measure the high-energy ductile X-ray energy spectrum, especially the continuous spectrum X-ray at the MeV level.
An energy spectrum measurement device including a collimator, a shield, a multi-layer absorption measurement assembly and a processor are adopted. After the electron beam tough radiation X-ray passes through the collimator and shield, it irradiates the multi-layer absorption measurement assembly. The processor determines the energy spectrum data based on the absorption dose of the Si dose sheet.
The measurement of the X-ray energy spectrum of the wide energy region of the electron beam tough radiation MeV is achieved, and the problem of the reduction in the efficiency of traditional detectors in high-energy X-ray measurement is overcome.
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Figure CN119882012A_ABST
Abstract
Description
Technical Field
[0001] The present application relates to the field of ray detection and measurement, and in particular to a device and method for measuring the energy spectrum of bremsstrahlung X-rays. Background Art
[0002] At present, electron accelerators are widely used in various fields such as radiotherapy, irradiation processing, irradiation sterilization, non-destructive testing, etc. For example, medical electron accelerators usually use linear accelerators to accelerate electrons to 6MeV or 8MeV energy, bombard tungsten targets to generate X-rays through bremsstrahlung, and collimate the X-rays to treat tumors.
[0003] In the process of electron accelerator X-ray radiotherapy, irradiation sterilization, non-destructive testing and other applications, the X-rays generated by electron bombardment target bremsstrahlung are continuous spectra with a wide energy range. The penetration ability and radiation effect of X-rays of different energies in matter are different. For the needs of dose calibration and calculation, radiation shielding design, etc., it is usually necessary to experimentally measure the energy spectrum of bremsstrahlung X-rays generated by electron target. X-rays are typical photon rays, and the detectors suitable for measuring their energy spectrum are mainly scintillator detectors, semiconductor detectors, etc.
[0004] The X-ray energy spectrum generated by the bremsstrahlung radiation of an electron beam with energy in the order of MeV bombarding a target is a continuous spectrum. When a scintillator detector or a semiconductor detector is used to measure the bremsstrahlung X-ray energy spectrum, the detection efficiency of the detector in the low-energy region of X-rays will increase with the increase of X-ray energy, but usually when the X-ray energy is greater than about 0.5MeV, the detection efficiency will drop rapidly with the increase of X-ray energy. In order to obtain a better bremsstrahlung continuous spectrum X-ray energy spectrum, it is necessary to use multiple standard monoenergetic photon sources of known intensity to calibrate the detector efficiency to obtain an efficiency calibration curve. However, due to the limitations of the number of available standard monoenergetic photon sources and photon energy, usually only the efficiency calibration curve for photon energies below 3MeV can be given, and the efficiency calibration data for the energy region with photon energies greater than 3MeV cannot be determined experimentally. Therefore, current detectors cannot directly measure the higher energy bremsstrahlung X-ray energy spectrum. Summary of the invention
[0005] The purpose of the present application is to provide a device and method for measuring the energy spectrum of bremsstrahlung X-rays, which can realize the measurement of the energy spectrum of electron beam bremsstrahlung X-rays in a wide energy range of MeV.
[0006] To achieve the above objectives, this application provides the following solutions:
[0007] In a first aspect, the present application provides a device for measuring the energy spectrum of bremsstrahlung X-rays, comprising: a collimator, a shield, a multi-layer absorption measurement component and a processor;
[0008] The collimator is provided with an X-ray collimation channel inside; the shield is coaxially mounted with the collimator; the shield is provided with a mounting channel inside; the multi-layer absorption measurement component is arranged in the mounting channel of the shield; the multi-layer absorption measurement component comprises a plurality of absorption sheets and a plurality of Si dose sheets arranged in sequence and at intervals;
[0009] After the electron beam bremsstrahlung X-rays pass through the X-ray collimation channel of the collimator, the multilayer absorption measurement assembly is irradiated with X-rays in the mounting channel of the shielding body;
[0010] The processor is used to determine the energy spectrum data of the electron beam bremsstrahlung X-ray according to the X-ray absorption dose of each Si dose sheet.
[0011] Optionally, the number of the absorption sheets is 9, and the number of the Si dosage sheets is 10.
[0012] Optionally, the X-ray collimation channel is conical in shape.
[0013] Optionally, the processor includes:
[0014] An energy region division module is used to divide the energy spectrum of the electron beam bremsstrahlung X-ray into multiple energy regions;
[0015] An equation building module, used for building an iterative equation according to which the X-ray absorption dose of each Si dose sheet is equal to the sum of the absorption doses generated by the X-rays in each energy zone in the Si dose sheet;
[0016] The energy spectrum determination module is used to substitute the X-ray absorption doses of multiple Si dose sheets into the iterative equation for iterative calculation, determine the relative intensity of X-rays in each energy zone, and obtain the energy spectrum data of electron beam bremsstrahlung X-rays.
[0017] Optionally, the iterative equation is:
[0018]
[0019] in, is the relative intensity of X-rays obtained after the kth iteration in the jth energy region, is the relative intensity of X-rays obtained after the k+1th iteration in the jth energy region, D i is the X-ray absorbed dose of the ith Si dose sheet, m is the number of Si dose sheets, n is the number of energy zones, is the weight function, B ij is the response matrix data of the ith Si dose sheet in the jth energy zone, ρ 0i is the relative standard deviation of the X-ray absorbed dose of the ith Si dose sheet.
[0020] Optionally, the termination condition of the iterative calculation is
[0021] Optionally, the energy spectrum measuring device of the bremsstrahlung X-ray further comprises: a Si dose sheet measuring instrument; the Si dose sheet measuring instrument is used to measure the X-ray absorption dose of each Si dose sheet.
[0022] Optionally, the collimator has a diameter of 400 mm and a length of 300 mm; the entrance diameter of the X-ray collimation channel is 30 mm and the exit diameter is 60 mm; the shielding body has a diameter of 260 mm and a length of 300 mm; and the mounting channel has a diameter of 60 mm.
[0023] In a second aspect, the present application provides a method for measuring an energy spectrum of bremsstrahlung X-rays, comprising:
[0024] The electron beam bremsstrahlung X-rays are collimated through the X-ray collimation hole of the collimator, and the collimated electron beam bremsstrahlung X-rays enter the installation hole of the shielding body to irradiate the multi-layer absorption measurement assembly with X-rays;
[0025] The processor determines the energy spectrum data of the electron beam bremsstrahlung X-ray according to the X-ray absorption dose of each Si dose sheet.
[0026] Optionally, the energy spectrum data of the electron beam bremsstrahlung X-rays is determined according to the X-ray absorption dose of each Si dose sheet, specifically including:
[0027] Divide the energy spectrum of electron beam bremsstrahlung X-rays into multiple energy regions;
[0028] An iterative equation is constructed based on the X-ray absorption dose of each Si dose sheet being equal to the sum of the absorption doses generated by X-rays in each energy zone in the Si dose sheet;
[0029] Substituting the X-ray absorption doses of multiple Si dose sheets into the iterative equation for iterative calculation, the relative intensity of X-rays in each energy range is determined to obtain energy spectrum data of electron beam bremsstrahlung X-rays.
[0030] According to the specific embodiments provided in this application, this application discloses the following technical effects:
[0031] The present application provides an energy spectrum measurement device and method for bremsstrahlung X-rays. A multilayer absorption measurement component is irradiated with X-rays by electron beam bremsstrahlung X-rays. The multilayer absorption measurement component includes a plurality of absorption sheets and a plurality of Si dose sheets that are sequentially arranged at intervals. After the irradiation is completed, the energy spectrum data of the electron beam bremsstrahlung X-rays are determined according to the X-ray absorption dose of each Si dose sheet. This overcomes the difficulty that the high-energy X-ray detection efficiency cannot be calibrated when the conventional detector system is used to directly measure the energy spectrum of the bremsstrahlung MeV continuous spectrum X-rays, and realizes the measurement of the electron beam bremsstrahlung MeV wide energy range X-ray energy spectrum. BRIEF DESCRIPTION OF THE DRAWINGS
[0032] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.
[0033] Figure 1 A schematic diagram of the structure of a device for measuring the energy spectrum of bremsstrahlung X-rays provided in one embodiment of the present application;
[0034] Figure 2 A schematic diagram of an iterative algorithm in an embodiment of the present application;
[0035] Figure 3 A flow chart of a method for measuring an energy spectrum of bremsstrahlung X-rays provided in one embodiment of the present application.
[0036] Figure numerals: 1-X-ray source, 2-X-ray collimation channel, 3-collimator, 4-shielding body, 5-absorption plate, 6-installation channel, 7-Si dose plate. DETAILED DESCRIPTION
[0037] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in 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. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.
[0038] In order to make the above-mentioned objects, features and advantages of the present application more obvious and easy to understand, the present application is further described in detail below with reference to the accompanying drawings and specific implementation methods.
[0039] In an exemplary embodiment, Figure 1 As shown, a device for measuring the energy spectrum of bremsstrahlung X-rays is provided, comprising: a collimator 3, a shielding body 4, a multi-layer absorption measurement component and a processor.
[0040] The collimator 3 is used to collimate the electron beam bremsstrahlung X-rays from the electron accelerator into one beam.
[0041] The collimator 3 has an X-ray collimation channel 2 disposed inside. The shielding body 4 is coaxially mounted with the collimator 3. The shielding body 4 has an installation channel 6 disposed inside. The multi-layer absorption measurement assembly is disposed in the installation channel 6 of the shielding body 4. The multi-layer absorption measurement assembly includes a plurality of absorption sheets 5 and a plurality of Si dose sheets 7 disposed sequentially and spaced apart.
[0042] In a specific application example, the number of the absorption sheets 5 is 9, and the number of the Si dose sheets 7 is 10. The shape of the X-ray collimation channel 2 is conical. The diameter of the collimator 3 is 400 mm and the length is 300 mm. The entrance diameter of the X-ray collimation channel 2 is 30 mm and the exit diameter is 60 mm. The diameter of the shielding body 4 is 260 mm and the length is 300 mm. The diameter of the mounting channel 6 is 60 mm. The geometric thickness of the absorption sheet 5 is 20 mm.
[0043] In a specific application example, the main body of the energy spectrum measuring device for bremsstrahlung X-rays is a cylindrical structure. The absorber 5 is an X-ray iron absorber, the Si dose plate 7 is an X-ray Si dose plate, the collimator 3 is an X-ray lead collimator, and the shield 4 is an X-ray lead shield.
[0044] After the electron beam bremsstrahlung X-rays pass through the X-ray collimation channel 2 of the collimator 3 , the multi-layer absorption measurement assembly is irradiated with X-rays in the mounting channel 6 of the shielding body 4 .
[0045] In addition, the energy spectrum measuring device of the bremsstrahlung X-ray further comprises a Si dose sheet measuring instrument, which is used to measure the X-ray absorption dose of each Si dose sheet 7 .
[0046] The electron beam bremsstrahlung X-rays are emitted from the X-ray source 1. When performing X-ray measurement, the axis of the bremsstrahlung X-ray spectrum measuring device is aligned with a certain angle direction of the measured X-ray source 1, and the multi-layer absorption measurement assembly is irradiated with X-rays for a sufficient time when the X-ray source 1 emits a beam. After the irradiation, 10 Si dose sheets 7 are removed from the multi-layer absorption measurement assembly, and the X-ray absorption dose of each Si dose sheet 7 is measured using a calibrated Si dose sheet measuring instrument.
[0047] The processor is used to determine the energy spectrum data of the electron beam bremsstrahlung X-rays according to the X-ray absorption dose of each Si dose sheet 7 .
[0048] Specifically, a group of equations is established based on the physical principle of X-ray absorption in the absorption sheet 5 and the absorbed doses measured by the first Si dose sheet 7 and the Si dose sheets 7 after different absorption sheets 5 obtained by experimental measurement, and an iterative equation is constructed based on the group of equations. The energy spectrum data of the X-rays is determined through iterative numerical calculation.
[0049] In a specific application example, the processor includes: an energy region division module, an equation construction module and an energy spectrum determination module.
[0050] The energy region division module is used to divide the energy spectrum of the electron beam bremsstrahlung X-ray into multiple energy regions.
[0051] The equation building module is used to build an iterative equation based on the X-ray absorption dose of each Si dose plate 7 being equal to the sum of the absorption doses generated by the X-rays in each energy zone in the Si dose plate 7 .
[0052] The intensity I of the electron beam bremsstrahlung X-ray after passing through the absorber 5 can be described by the following equation:
[0053] I=I0e -μ.x ;
[0054] Where I0 is the intensity of the electron beam bremsstrahlung X-ray (s -1 ), μ is the mass attenuation coefficient of the absorber 5 for electron beam bremsstrahlung X-rays (cm 2 / g), x is the mass thickness ratio of the absorbent sheet 5 (g / cm 2 ).
[0055] The energy spectrum of electron beam bremsstrahlung X-rays is divided into n energy regions. Suppose the incident X-ray intensities in the n energy regions are I 01 ,I 02 ,I 03 ,…,I 0n The X-ray absorbed doses of the first Si metering piece to the tenth Si metering piece are D1, D2, D3, D4, ..., D 10 (Gy), and then according to the X-ray absorption dose of each Si dose plate 7 being equal to the sum of the absorption doses generated by the X-rays in each energy zone in the Si dose plate 7, and ignoring the influence of the X-ray absorption in the Si dose plate 7 on its intensity, the dose D of the i-th Si dose plate 7 is i It can be described by the following equation:
[0056]
[0057] in, i=1,2,…10; j=1,2…n; b1, b2, b3,…, b nare the absorbed doses produced by unit intensity X-rays in the Si dose sheet from the 1st energy range to the nth energy range, that is, the energy deposition of X-rays in the Si dose sheet, in Gy, which can be determined by simulating the energy deposition of single-energy X-rays in n energy ranges in the Si dose sheet using the Monte Carlo method; μ1, μ2, μ3…μ n are the mass attenuation coefficients of X-rays in Fe from the 1st energy range to the nth energy range, and the recommended data in the database can be used. i is the mass thickness of the Fe absorber that the X-ray passes through before reaching the i-th Si dose plate 7. Assuming that the mass thickness of the 9 Fe absorbers is the same, which is d, then x1 = 0; x2 = d; x3 = 2d; ... x 10 =9d. According to the rules of the GRAVEL iterative algorithm, I in the above equation 0j The solution can be transformed into the following iterative equation:
[0058]
[0059] in, is the relative intensity of X-rays obtained after the kth iteration in the jth energy region, is the relative intensity of X-rays obtained after the k+1th iteration in the jth energy region, D i is the X-ray absorbed dose of the i-th Si dose plate 7, m is the number of Si dose plates 7, n is the number of energy zones, is the weight function, is the X-ray absorbed dose of the i-th Si dose plate 7 after the k-th iteration, B ij is the response matrix data of the i-th Si dose sheet 7 in the j-th energy zone, ρ 0i is the relative standard deviation of the X-ray absorbed dose of the i-th Si dose plate 7, D 0i is the average value of the X-ray absorbed dose of the i-th Si dose plate 7, σ 0i D 0i The standard deviation of the data.
[0060] The energy spectrum determination module is used to substitute the X-ray absorption doses of multiple Si dose sheets 7 into the iterative equation for iterative calculation, and determine the relative intensity of X-rays in each energy region to obtain energy spectrum data of electron beam bremsstrahlung X-rays.
[0061] The end condition of the iterative calculation is:
[0062] Specifically, Figure 2 As shown, first, the Si dose slice dose data D (including the X-ray absorption dose D of each dose slice) is read in. i) and response matrix data B (including the response matrix B for each dose tablet ij ); Set the initial value The initial values of the n energy zones can all be set to 1, that is, Will Substituting into the iterative equation gives Then The iterative equation can be calculated to get Repeat the above calculation process until the X-ray energy spectrum data obtained by the k+1th iteration satisfies Then the iterative calculation is terminated, and the relative intensity of X-rays in n energy regions can be obtained, which is the energy spectrum data of electron beam bremsstrahlung X-rays.
[0063] The present application overcomes the difficulty of being unable to calibrate the high-energy X-ray detection efficiency when using a traditional detector system to directly measure the MeV continuous spectrum X-ray energy spectrum of bremsstrahlung radiation, and realizes the measurement of the MeV wide energy range X-ray energy spectrum of electron beam bremsstrahlung radiation, which is universal.
[0064] Based on the same inventive concept, the embodiment of the present application also provides a method for applying the above-mentioned bremsstrahlung X-ray energy spectrum measurement device. The implementation scheme for solving the problem provided by the method is similar to the implementation scheme recorded in the above-mentioned method, so the specific limitations in one or more embodiments of the bremsstrahlung X-ray energy spectrum measurement method provided below can refer to the above-mentioned limitations on the bremsstrahlung X-ray energy spectrum measurement device, and will not be repeated here.
[0065] In an exemplary embodiment, Figure 3 As shown, a method for measuring the energy spectrum of bremsstrahlung X-rays is provided, including step 31 and step 32.
[0066] Step 31, collimating the electron beam bremsstrahlung X-rays through the X-ray collimation hole of the collimator, and the collimated electron beam bremsstrahlung X-rays enter the installation hole of the shielding body to irradiate the multi-layer absorption measurement assembly with X-rays.
[0067] Step 32: determining the energy spectrum data of the electron beam bremsstrahlung X-rays according to the X-ray absorption dose of each Si dose sheet by a processor.
[0068] The technical features of the above embodiments may be combined arbitrarily. To make the description concise, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.
[0069] This article uses specific examples to illustrate the principles and implementation methods of this application. The description of the above embodiments is only used to help understand the method and core ideas of this application. At the same time, for those skilled in the art, according to the ideas of this application, there will be changes in the specific implementation methods and application scope. In summary, the content of this specification should not be understood as limiting this application.
Claims
1. A device for measuring the energy spectrum of bremsstrahlung X-rays, characterized in that: The energy spectrum measuring device of the bremsstrahlung X-ray comprises: a collimator, a shield, a multi-layer absorption measurement component and a processor; The collimator is provided with an X-ray collimation channel inside; the shield is coaxially mounted with the collimator; the shield is provided with a mounting channel inside; the multi-layer absorption measurement component is arranged in the mounting channel of the shield; the multi-layer absorption measurement component comprises a plurality of absorption sheets and a plurality of Si dose sheets arranged in sequence and at intervals; After the electron beam bremsstrahlung X-rays pass through the X-ray collimation channel of the collimator, the multilayer absorption measurement assembly is irradiated with X-rays in the mounting channel of the shielding body; The processor is used to determine the energy spectrum data of the electron beam bremsstrahlung X-ray according to the X-ray absorption dose of each Si dose sheet.
2. The device for measuring the energy spectrum of bremsstrahlung X-rays according to claim 1, characterized in that: The number of the absorption sheets is 9, and the number of the Si dosage sheets is 10.
3. The device for measuring the energy spectrum of bremsstrahlung X-rays according to claim 1, characterized in that: The X-ray collimation channel is in a cone shape.
4. The device for measuring the energy spectrum of bremsstrahlung X-rays according to claim 1, characterized in that: The processor comprises: An energy region division module is used to divide the energy spectrum of the electron beam bremsstrahlung X-ray into multiple energy regions; An equation building module, used for building an iterative equation according to which the X-ray absorption dose of each Si dose sheet is equal to the sum of the absorption doses generated by the X-rays in each energy zone in the Si dose sheet; The energy spectrum determination module is used to substitute the X-ray absorption doses of multiple Si dose sheets into the iterative equation for iterative calculation, determine the relative intensity of X-rays in each energy zone, and obtain the energy spectrum data of electron beam bremsstrahlung X-rays.
5. The device for measuring the energy spectrum of bremsstrahlung X-rays according to claim 4, characterized in that: The iterative equation is: in, is the relative intensity of X-rays obtained after the kth iteration in the jth energy region, is the relative intensity of X-rays obtained after the k+1th iteration in the jth energy region, D i is the X-ray absorbed dose of the ith Si dose sheet, m is the number of Si dose sheets, n is the number of energy zones, is the weight function, B ij is the response matrix data of the ith Si dose sheet in the jth energy zone, ρ 0i is the relative standard deviation of the X-ray absorbed dose of the ith Si dose sheet.
6. The device for measuring the energy spectrum of bremsstrahlung X-rays according to claim 4, characterized in that: The end condition of the iterative calculation is 7. The device for measuring the energy spectrum of bremsstrahlung X-rays according to claim 1, characterized in that: The energy spectrum measuring device of the bremsstrahlung X-ray further comprises: a Si dose sheet measuring instrument; the Si dose sheet measuring instrument is used to measure the X-ray absorption dose of each Si dose sheet.
8. The device for measuring the energy spectrum of bremsstrahlung X-rays according to claim 1, characterized in that: The collimator has a diameter of 400 mm and a length of 300 mm; the entrance diameter of the X-ray collimation channel is 30 mm and the exit diameter is 60 mm; the shield has a diameter of 260 mm and a length of 300 mm; and the installation channel has a diameter of 60 mm.
9. A method for measuring the energy spectrum of bremsstrahlung X-rays, using the device for measuring the energy spectrum of bremsstrahlung X-rays according to any one of claims 1 to 8, characterized in that: The method for measuring the energy spectrum of bremsstrahlung X-rays comprises: The electron beam bremsstrahlung X-rays are collimated through the X-ray collimation hole of the collimator, and the collimated electron beam bremsstrahlung X-rays enter the installation hole of the shielding body to irradiate the multi-layer absorption measurement assembly with X-rays; The processor determines the energy spectrum data of the electron beam bremsstrahlung X-ray according to the X-ray absorption dose of each Si dose sheet.
10. The method for measuring the energy spectrum of bremsstrahlung X-rays according to claim 9, characterized in that: The energy spectrum data of electron beam bremsstrahlung X-rays are determined based on the X-ray absorption dose of each Si dose sheet, including: Divide the energy spectrum of electron beam bremsstrahlung X-rays into multiple energy regions; An iterative equation is constructed based on the fact that the X-ray absorption dose of each Si dose sheet is equal to the sum of the absorption doses generated by X-rays in each energy zone in the Si dose sheet; Substituting the X-ray absorption doses of a plurality of Si dose sheets into the iterative equation for iterative calculation, the relative intensity of X-rays in each energy region is determined to obtain energy spectrum data of electron beam bremsstrahlung X-rays.