BIXS method for analyzing tritium-containing sample with unknown thickness

Abstract

The invention discloses a BIXS method for analyzing a tritium-containing sample with an unknown thickness. The method comprises the following steps: dividing the tritium-containing sample with an unknown actual tritium absorption depth t into M layers from top to bottom; obtaining a tritium beta decay X-ray energy spectrum when each layer in the M layers independently contains tritium, and forming an energy spectrum matrix; the total tritium beta decay X-ray energy spectrum generated before the tritium-containing sample is obtained through a BIXS experiment; calculating the depth distribution of M layers of tritium and the number M1 of layers actually containing tritium according to the sum energy spectrum matrix; and calculating the actual depth distribution of tritium according to the sum energy spectrum matrix. The tritium-containing sample can be analyzed under the condition that the actual absorption depth of tritium is unknown, and the efficiency of the BIXS analysis method is improved.

Description

Technical Field

[0001] This invention belongs to the field of diagnostic technology for solid-state tritium-containing materials in nuclear fusion, and specifically relates to a BIXS method for analyzing tritium-containing samples of unknown thickness. Background Technology

[0002] Accurate measurement of tritium content and depth distribution in materials is one of the core technological requirements across the entire nuclear fusion energy research and development chain. It plays an irreplaceable role in the design, construction, and decommissioning of key equipment such as tritium breeder blankets and tritium processing and recovery systems in fusion reactors, as well as in the performance evaluation and safety analysis of key tritium-containing materials such as fusion targets and first wall materials. The depth distribution of tritium in materials not only reflects its deposition or infiltration process but also reveals the material's tritium retention characteristics. For example, in nuclear fusion devices, the amount of tritium residue on the surface of plasma materials affects the stability of subsequent plasma, while the distribution within the bulk phase is related to the material's tritium storage capacity. By obtaining depth distribution information, material selection can be optimized, surface treatment processes improved, and the risk of tritium retention reduced.

[0003] Tritium β decay produces a continuous electron energy spectrum with a maximum energy of 18.6 keV. After the material absorbs tritium, the tritium... Decaying electrons interact with tritium-absorbing materials to produce external bremsstrahlung (EB) and characteristic X-rays. During the β decay process, tritium also emits a photon with a certain probability, which is internal bremsstrahlung (IB).

[0004] Beta-ray induced X-ray spectrometry (BIXS) is a non-destructive analytical method that analyzes the tritium content and depth distribution in materials by detecting the X-ray energy spectrum generated by tritium decay beta rays. Compared with conventional tritium analysis methods, BIXS has a greater analytical depth, with an analytical depth of ~0.1 mm for high-Z elements and up to 1 mm for low-Z elements. BIXS analysis has been applied to the analysis of tritium content and depth distribution in solid and liquid materials in nuclear fusion devices.

[0005] There are three types of BIXS analysis methods: the analytical BIXS analysis method proposed by Matsuyama et al., the Monte Carlo BIXS analysis method proposed by Anzhu et al., and the semi-analytical BIXS analysis method proposed by Huang Hong et al.

[0006] The analytical BIXS method, developed by Matsuyama et al., relies on semi-empirical formulas to obtain the X-ray energy spectra of tritium β decay at different depths. It mainly consists of three steps: assuming an initial tritium depth and analytically obtaining the tritium β decay electron energy spectrum; analytically converting the tritium β decay electron energy spectrum to an X-ray energy spectrum; analytically attenuating the X-rays at different depths and obtaining the total attenuated tritium β decay X-ray energy spectrum; comparing the analytical X-ray energy spectrum with the experimental spectrum; if the experimental and analytical spectra are consistent, the current tritium depth distribution information is considered the actual tritium depth distribution information; otherwise, the tritium depth distribution information is modified and the iteration continues. However, the analytical BIXS method proposed by Matsuyama et al. cannot account for geometric complexity and the scattering of electrons and photons within the material during the analytical process, resulting in inaccurate calculation results.

[0007] The Monte Carlo BIXS analysis method, proposed by An Zhu et al., uses the Monte Carlo (MC) program to simulate and obtain the X-ray energy spectrum of tritium beta decay at different depths. The MC program accurately models the spectrum, fully considering geometric complexity and electron and photon scattering issues. However, because the Monte Carlo program is based on mathematical statistics and probability, and the detector solid angle of BIXS experimental setups is typically small, obtaining simulated X-ray energy spectra of tritium beta decay with small statistical errors requires a large computer cluster and results in long computation times. Therefore, the overall analysis time of the MC BIXS method is long and its efficiency is low.

[0008] The semi-analytical BIXS analysis method proposed by Huang Hong et al. combines the advantages of the Matsuyama analytical method and the Yasutaka Monte Carlo simulation. It simulates the spatial distribution of electrons and characteristic X-rays through the Monte Carlo program and replaces the time-consuming part of the MC BIXS method with analytical methods, thus significantly improving the analysis efficiency while ensuring computational accuracy.

[0009] All three existing BIXS analysis methods require prior knowledge of the actual tritium distribution thickness within the sample, then dividing the actual tritium distribution thickness into M layers, and finally obtaining the X-ray energy spectrum of each layer containing tritium individually.

[0010] It is the total energy spectrum of tritium beta decay X-rays received by the detector. It is the X-ray energy spectrum of each layer containing tritium individually. This refers to the depth distribution of tritium. Existing BIXS analysis methods typically require obtaining sample thickness in advance using other measurement methods before sample stratification, significantly reducing the efficiency of BIXS analysis. For tritium-containing samples with unknown thickness, existing BIXS methods cannot directly measure them. The patent "An Efficient Tritium Analysis Method, Apparatus, Device, and Storage Medium" (Patent No.: ZL 2021 1 1188910.3) proposes an efficient tritium analysis method, apparatus, device, and storage medium. It uses a trained tritium analysis calculation model to predict tritium content and sample thickness. However, constructing this model requires a large amount of tritium β-decay X-ray energy spectrum data and the corresponding relationship between tritium depth distribution and sample thickness, making the construction process time-consuming and labor-intensive.

[0011] Therefore, it is necessary to propose a BIXS method for the analysis of tritium-containing samples of unknown thickness, to address the shortcomings of existing BIXS analysis methods that require prior knowledge of sample thickness, and to quickly obtain the tritium depth distribution and thickness information of tritium-containing samples. Summary of the Invention

[0012] To overcome the aforementioned shortcomings, the inventors of this invention, through long-term exploration, experimentation, and continuous innovation, have proposed a BIXS method for analyzing tritium-containing samples of unknown thickness, which can quickly obtain the tritium depth distribution and thickness information of tritium-containing samples.

[0013] To achieve the above objectives, the technical solution adopted by this invention is: to provide a BIXS method for analyzing tritium-containing samples of unknown thickness. This includes the following steps: S1. Divide the tritium-containing sample with unknown actual tritium absorption depth t into M layers from top to bottom; S2. Obtain the X-ray energy spectrum of tritium β decay when each layer in layer M contains tritium alone, and construct an energy spectrum matrix. ; S3. Total tritium β decay X-ray energy spectrum obtained from the BIXS experiment before the tritium-containing sample was obtained. ; S4, by and energy spectrum matrix The depth distribution of the M layer of tritium was calculated. And the actual number of tritium-containing layers, M1; S5. The energy spectrum matrix is ​​composed of the X-ray energy spectra of tritium β decay when each layer in the first M1 layer contains tritium alone. ,Depend on and energy spectrum matrix The actual depth distribution of tritium was calculated. .

[0014] A further preferred embodiment of the BIXS method for analyzing tritium-containing samples of unknown thickness according to the present invention is that the tritium-containing sample refers to a thin solid tritium-containing sample containing a substrate or a thick solid tritium-containing sample. A further preferred technical solution of the BIXS method for analyzing tritium-containing samples of unknown thickness according to the present invention is that, when the actual tritium absorption depth t is unknown, the thickness range of the stratification should be greater than the actual tritium absorption depth t.

[0015] A further preferred embodiment of the BIXS method for analyzing tritium-containing samples of unknown thickness according to the present invention is as follows: In step S1, when stratifying the tritium-containing sample, a uniform stratification or a non-uniform stratification method is adopted. The thickness of the tritium-containing sample is used To express.

[0016] According to the BIXS method for analyzing tritium-containing samples of unknown thickness as described in this invention, a further preferred technical solution is: in step S2, the method for obtaining the tritium β decay X-ray energy spectrum of each layer containing tritium individually is Monte Carlo simulation or analytical method. The Monte Carlo program adopts any one of PENELOPE, GEANT4, MCNP, or EGS that can simultaneously simulate electron and photon transport.

[0017] A further preferred embodiment of the BIXS method for analyzing tritium-containing samples of unknown thickness according to the present invention is as follows: In step S2, the formula for obtaining the tritium β-decay X-ray energy spectrum of each individual tritium layer is as follows: in, Indicates the first The X-ray energy spectrum of tritium β decay when the layer contains only tritium, where N is the number of channels on the x-axis of the tritium β decay X-ray energy spectrum. It is the first The X-ray count or count rate in the j-th channel of the tritium β decay X-ray energy spectrum when the layer contains only tritium.

[0018] A further preferred technical solution of the BIXS method for analyzing tritium-containing samples of unknown thickness according to the present invention is: constructing a matrix. The formula is , , , and Representing the 1st, 2nd, 3rd, and 4th floors respectively. X-ray energy spectra of tritium β decay when layer M and layer M each contain tritium individually.

[0019] A further preferred embodiment of the BIXS method for analyzing tritium-containing samples of unknown thickness according to the present invention is as follows: In step S3, in, N It represents the number of x-axis coordinates in the X-ray energy spectrum of tritium beta decay, which is also the number of channel addresses. , , , and These represent the X-ray counts in channels 1, 2, 3, j, and N of the BIXS experimental energy spectrum, respectively.

[0020] A further preferred embodiment of the BIXS method for analyzing tritium-containing samples of unknown thickness according to the present invention is as follows: In step S4, Where M1 is less than or equal to M, , , , and Representing the 1st, 2nd, 3rd, and 4th floors respectively. The tritium content in the Mth and Mth layers is close to 0 in layers greater than M1.

[0021] A further preferred embodiment of the BIXS method for analyzing tritium-containing samples of unknown thickness according to the present invention is as follows: In step S5, These represent the X-ray energy spectra of tritium β decay when the M1 layer contains only tritium. .

[0022] Compared with the prior art, the technical solution of the present invention has the following advantages / benefits: 1. This invention addresses the shortcomings of existing BIXS analysis methods, which require prior knowledge of the tritium-containing sample thickness and cannot directly measure tritium-containing samples of unknown thickness. It proposes a highly efficient BIXS method for analyzing tritium-containing samples of unknown thickness. This method can simultaneously analyze the thickness and tritium depth distribution of a tritium-containing sample without knowing its thickness. First, assuming the thickness range of the stratified samples is greater than the actual absorption depth t of tritium, the depth distribution is calculated by inverting the energy spectrum matrix and experimental energy spectrum with the maximum number of layers. Then, the true thickness of the tritium-containing sample is obtained based on the calculation results. Finally, the true tritium depth distribution is obtained by inverting the calculation again using the obtained true thickness and the energy spectrum matrix and experimental energy spectrum. Attached Figure Description

[0023] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of the present invention and should not be regarded as a limitation of the scope. For those skilled in the art, other related drawings can be obtained from these drawings without creative effort.

[0024] Figure 1 This is a flowchart of a BIXS method for analyzing tritium-containing samples of unknown thickness according to the present invention.

[0025] Figure 2 This is a schematic diagram of the layering of tritium-containing samples in the BIXS analysis method of this invention.

[0026] Figure 3 This refers to the BIXS experimental apparatus used in the simulation and experimentation in this embodiment of the invention.

[0027] Figure 4 In this embodiment of the invention, when each of layers 1 to 10 contains tritium individually, the tritium-to-zirconium ratio is 1.5 and the thickness is 4.94 mm, obtained through PENELOPE simulation. of Depth distribution of electrons within the sample and its surrounding materials (Al film and Mo substrate).

[0028] Figure 5 This is the BIXS experimental spectrum of the zirconium tritide sample in the embodiments of the present invention.

[0029] Figure 6 The depth distribution of tritium within the 20 layers is calculated from the tritium β decay X-ray energy spectrum matrix of each of the 20 layers containing tritium individually and the BIXS experimental energy spectrum of the tritium-containing sample in this embodiment of the invention.

[0030] Figure 7The actual depth distribution of tritium in this embodiment of the invention is calculated from the tritium β decay X-ray energy spectrum of each of the first 10 layers containing tritium individually and the BIXS experimental energy spectrum of the tritium-containing sample.

[0031] Figure 8 In the embodiments of the present invention, by Figure 7 Comparison of fitted X-ray energy spectra of tritium obtained from the depth distribution in the middle layer with experimental energy spectra. Detailed Implementation

[0032] To make the objectives, technical solutions, and advantages of this invention clearer, the technical solutions in the embodiments of this invention are described clearly and completely below. Obviously, the described embodiments are only a part of the embodiments of this invention, not all of them. Based on the embodiments of this invention, all other embodiments obtained by those skilled in the art without inventive effort are within the scope of protection of this invention. Therefore, the detailed description of the embodiments of this invention provided below is not intended to limit the scope of the claimed invention, but merely represents selected embodiments of the invention.

[0033] Example 1: like Figure 1 The diagram illustrates a BIXS method for analyzing tritium-containing samples of unknown thickness. It includes the following steps: S1. Divide the tritium-containing sample with an unknown actual tritium absorption depth t into M layers from top to bottom; when layering the tritium-containing sample, use either uniform or non-uniform layering methods. The thickness of the tritium-containing sample is used This means that, in the absence of an known actual tritium absorption depth t, the thickness range of the stratification should be as large as possible to ensure that the thickness range of the stratification is greater than the actual tritium absorption depth t.

[0034] S2. Obtain the X-ray energy spectrum of tritium β decay when each layer in layer M contains tritium alone, and construct an energy spectrum matrix. The methods for obtaining the X-ray energy spectrum of tritium β decay when each layer contains tritium alone are the Monte Carlo simulation method and the analytical method. The Monte Carlo program used is any one of PENELOPE, GEANT4, MCNP, or EGS that can simultaneously simulate electron and photon transport. The formula for obtaining the X-ray energy spectrum of tritium β decay when each layer contains tritium alone is as follows: in, Indicates the first The X-ray energy spectrum of tritium β decay when the layer contains only tritium, where N is the number of channels on the x-axis of the tritium β decay X-ray energy spectrum. It is the first The X-ray count or count rate of the j-th channel in the X-ray energy spectrum of tritium β decay when the layer contains only tritium; constituting a matrix. The formula is , , , and Representing the 1st, 2nd, 3rd, and 4th floors respectively. X-ray energy spectra of tritium β decay when layer M and layer M each contain tritium individually. S3. Total tritium β decay X-ray energy spectrum obtained from the BIXS experiment before the tritium-containing sample was obtained. ; in, N It represents the number of x-axis coordinates in the X-ray energy spectrum of tritium beta decay, which is also the number of channel addresses. , , , and These represent the X-ray counts in channels 1, 2, 3, j, and N of the BIXS experimental energy spectrum, respectively.

[0035] S4, by and energy spectrum matrix The depth distribution of the M layer of tritium was calculated. And the actual number of tritium-containing layers, M1; Where M1 is less than or equal to M, , , , and Representing the 1st, 2nd, 3rd, and 4th floors respectively. The tritium content in the Mth and Mth layers is close to 0 in layers greater than M1.

[0036] S5. The energy spectrum matrix is ​​composed of the X-ray energy spectra of tritium β decay when each layer in the first M1 layer contains tritium alone. ,Depend on and energy spectrum matrix The actual depth distribution of tritium was calculated. .

[0037] These represent the X-ray energy spectra of tritium β decay when the M1 layer contains only tritium. .

[0038] It should be noted that the tritium-containing sample mentioned in this method refers to a solid thin tritium-containing sample containing a substrate or a thick solid tritium-containing sample, including solid samples containing tritium such as titanium tritide, zirconium tritide, and tungsten tritide.

[0039] Example 2: Based on Example 1, the following is a practical example, such as... Figure 2 As shown, in step S1, the tritium-containing sample is uniformly divided into M layers from top to bottom; however, only layer M1 actually contains tritium. In this embodiment, the tritium-zirconium ratio is 1.5, and the thickness is 4.94 mm. of Taking the sample as an example, M equals 20, the thickness of each layer is 0.494 μm, and M1 equals 10.

[0040] When the actual tritium absorption depth t is unknown, the thickness range of the layer should be as large as possible to ensure that the layer thickness range is greater than the actual tritium absorption depth t. In this embodiment, the layer thickness is 9.88 μm, and the actual tritium absorption depth t is 4.94 μm.

[0041] S2. Obtain the X-ray energy spectrum of tritium β decay when each layer in layer M contains tritium alone, and construct an energy spectrum matrix. ;use Figure 3 The BIXS experimental setup in the middle obtained the first... X-ray energy spectrum of tritium β decay when the layer contains only tritium . It is the first Tritium when the layer contains only tritium The X-ray count or count rate in the j-th channel of the decay X-ray energy spectrum.

[0042] Obtain the energy spectrum matrix F NM , , , and Representing the 1st, 2nd, 3rd, and 4th floors respectively. X-ray energy spectra of tritium β decay when layer M and layer M each contain tritium individually.

[0043] like Figure 4 The figure shows the X-ray energy spectra of tritium β decay when the 1st, 5th, 10th, and 20th layers contain tritium, respectively. , , , The horizontal axis represents the energy of the X-rays, and the vertical axis represents the X-ray count at the corresponding X-ray energy. There are 200 channels on the horizontal axis, representing 200 energy ranges from 0 to 18.6 keV.

[0044] S3. Obtain the total tritium β decay X-ray energy spectrum generated in front of the tritium-containing sample by the BIXS experiment. ; This is the X-ray energy spectrum of tritium β decay obtained by the detector in front of the tritium-containing sample during the BIXS experiment.

[0045] N is the number of the horizontal axis in the X-ray energy spectrum of tritium β decay, which is also the number of channels. , , , and These represent the X-ray counts in channels 1, 2, 3, j, and N (the last channel) of the BIXS experimental energy spectrum, respectively.

[0046] like Figure 5 The image shows the BIXS experimental spectrum of the zirconium tritide sample in this embodiment.

[0047] The horizontal axis represents the energy of the X-rays, and the vertical axis represents the X-ray count at the corresponding X-ray energy. There are 200 channels on the horizontal axis, representing 200 energy ranges from 0 to 18.6 keV.

[0048] S4, by and energy spectrum matrix The depth distribution of the M layer of tritium was calculated. And the actual number of tritium-containing layers M1, obviously, requires M1 to be less than or equal to M. , , , and Representing the 1st, 2nd, 3rd, and 4th floors respectively. The tritium content in the first and M layers is almost zero in layers greater than M1.

[0049] Figure 6This is the tritium depth distribution within the 20 layers calculated from the tritium β-decay X-ray energy spectrum matrix of each of the 20 layers individually containing tritium and the BIXS experimental energy spectrum of the tritium-containing sample in this embodiment of the invention. It can be seen that the tritium content in layers beyond the 10th layer is 0.

[0050] S5, by and energy spectrum matrix The actual depth distribution of tritium was calculated. .

[0051] The energy spectrum matrix is ​​composed of the X-ray energy spectra of tritium β decay when each of the first M1 layers contains tritium individually. These represent the X-ray energy spectra of tritium β decay when the M1 layer contains only tritium.

[0052] Figure 7 The actual depth distribution of tritium in this embodiment of the invention is calculated from the tritium β decay X-ray energy spectrum of each of the first 10 layers containing tritium individually and the BIXS experimental energy spectrum of the tritium-containing sample.

[0053] Figure 8 In the embodiments of the present invention, it is composed of Figure 7 Comparison of fitted X-ray energy spectra of tritium obtained from the depth distribution in the middle layer with experimental energy spectra.

[0054] from Figure 8 As can be seen, the fitted X-ray energy spectrum is in excellent agreement with the experimental energy spectrum, proving the feasibility of the present invention.

[0055] Technical principle: Step 1: The original sample only contains 10 layers of tritium. First, the energy spectrum matrix of 20 layers and the experimental energy spectrum are used to invert and calculate the depth distribution of the 20 layers. The calculation result shows that only the first 10 layers have counts, and the last 10 layers are equal to 0 or close to 0. Thus, we obtain the true thickness of the tritium-containing sample (only 10 layers). Step 2: The energy spectrum matrix of the first 10 layers and the experimental energy spectrum are used to invert and calculate again to obtain the true depth distribution of tritium in the first 10 layers.

[0056] It should be noted that this embodiment can use plotting tools such as MATLAB, Excel, and Origin to process the data files output by Monte Carlo programs (such as PENELOPE), and this embodiment does not limit the software type of the plotting tool.

[0057] Based on the above description of the implementation methods, those skilled in the art can clearly understand that the present invention can be implemented using software and necessary general-purpose hardware, and of course, it can also be implemented using hardware, but in many cases the former is a better implementation method. Based on this understanding, the technical solution of the present invention, or the part that contributes to the prior art, can be embodied in the form of a software product. This computer software product can be stored in a computer-readable storage medium, such as a computer floppy disk, read-only memory (ROM), random access memory (RAM), flash memory, hard disk, or optical disk, etc., including several instructions to cause a set-top box (which may be a personal computer, server, or network device, etc.) to execute the methods described in the various embodiments of the present invention.

[0058] Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A BIXS method for analyzing tritium-containing samples of unknown thickness, characterized in that, Includes the following steps: S1. Divide the tritium-containing sample with unknown actual tritium absorption depth t into M layers from top to bottom; S2. Obtain the X-ray energy spectrum of tritium β decay when each layer in layer M contains tritium alone, and construct an energy spectrum matrix. ; S3. Obtain the total tritium β decay X-ray energy spectrum of the tritium-containing sample from the BIXS experiment. ; S4, by and energy spectrum matrix The depth distribution of the M layer of tritium was calculated. And the actual number of layers containing tritium, M1; S5. The energy spectrum matrix is ​​composed of the X-ray energy spectra of tritium β decay when each layer in the first M1 layer contains tritium alone. ,Depend on and energy spectrum matrix The actual depth distribution of tritium was calculated. .

2. The BIXS method for analyzing tritium-containing samples of unknown thickness according to claim 1, characterized in that, The tritium-containing sample refers to a thin solid tritium-containing sample containing a substrate or a thick solid tritium-containing sample.

3. The BIXS method for analyzing tritium-containing samples of unknown thickness according to claim 1, characterized in that, When the actual tritium absorption depth t is unknown, the thickness range of the stratification should be greater than the actual tritium absorption depth t.

4. The BIXS method for analyzing tritium-containing samples of unknown thickness according to claim 1 or 3, characterized in that, In step S1, when stratifying the tritium-containing sample, either uniform or non-uniform stratification methods are used. The thickness of the tritium-containing sample is used To express.

5. The BIXS method for analyzing tritium-containing samples of unknown thickness according to claim 1, characterized in that, In step S2, the method for obtaining the tritium β decay X-ray energy spectrum of each layer containing tritium individually is the Monte Carlo simulation method or the formula analysis method. The Monte Carlo program uses any one of PENELOPE, GEANT4, MCNP, or EGS to simultaneously simulate electron and photon transport.

6. The BIXS method for analyzing tritium-containing samples of unknown thickness according to claim 1 or 5, characterized in that, In step S2, the formula for obtaining the X-ray energy spectrum of tritium β decay when each layer contains tritium alone is as follows: in, Indicates the first The X-ray energy spectrum of tritium β decay when the layer contains only tritium, where N is the number of channels on the x-axis of the tritium β decay X-ray energy spectrum. It is the first The X-ray count or count rate in the j-th channel of the tritium β decay X-ray energy spectrum when the layer contains only tritium.

7. The BIXS method for analyzing tritium-containing samples of unknown thickness according to claim 6, characterized in that, Construct a matrix The formula is in, , , , and Representing the 1st, 2nd, 3rd, and 4th floors respectively. X-ray energy spectra of tritium β decay when layer M and layer M contain tritium individually.

8. The BIXS method for analyzing tritium-containing samples of unknown thickness according to claim 1, characterized in that, In step S3, in, N It represents the number of x-axis coordinates in the X-ray energy spectrum of tritium beta decay, which is also the number of channel addresses. , , , and These represent the X-ray counts in channels 1, 2, 3, j, and N of the BIXS experimental energy spectrum, respectively.

9. The BIXS method for analyzing tritium-containing samples of unknown thickness according to claim 1, characterized in that, In step S4, Where M1 is less than or equal to M, , , , and Representing the 1st, 2nd, 3rd, and 4th floors respectively. The tritium content in the Mth and Mth layers is close to 0 in layers greater than M1.

10. The BIXS method for analyzing tritium-containing samples of unknown thickness according to claim 1, characterized in that, In step S5, These represent the X-ray energy spectra of tritium β decay when the M1 layer contains only tritium. 。

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