A measuring device and data processing method for a gamma point source

Abstract

This application relates to the field of radiometric measurement technology, and provides a measuring device and data processing method for a gamma point source. The measuring device includes a first detector, a second detector, and a processing device. The first detector converts X-rays emitted by the gamma point source into a first pulse signal; the second detector converts gamma rays emitted by the gamma point source into a second pulse signal; the processing device is communicatively connected to both the first and second detectors, and can obtain the activity value of the gamma point source based on the first and second pulse signals. The measuring device and data processing method for a gamma point source provided in this application can directly measure the gamma point source.

Description

Technical Field

[0001] This application relates to the field of radiometric measurement technology, and in particular to a measuring device and data processing method for a gamma point source. Background Technology

[0002] Most radionuclides emit gamma nuclides, making gamma spectroscopy one of the most widely used techniques in radiometric measurements. Before being used in practical applications, a gamma spectrometer must be calibrated for efficiency using a gamma point source with a standard activity value. The accuracy and reliability of the gamma point source's activity value directly determines the quality of the gamma spectrometer's measurement and analysis results. Commonly used gamma point sources are mostly nuclides that undergo electron capture decay, such as... 54 Mn, 65 Zn, 88 Y、 109 Cd, 133 Ba and other compounds decay via an X-γ cascade.

[0003] In relative techniques, the activity value of a γ point source is determined by an absolute measuring device, namely a 4πX-γ coincidence measuring device, to measure the radioactive solution and obtain the standard specific activity value of the solution. Then, a sample is taken and accurately weighed to prepare a γ point source. In this way, the activity value of the γ point source can be calculated from the standard specific activity value of the radioactive solution and the mass of the sample. However, this absolute measuring device can only be used to measure radioactive solutions and cannot be used to directly measure γ point sources. Summary of the Invention

[0004] In view of this, embodiments of this application aim to provide a measurement device and data processing method for a gamma point source, which can directly measure the gamma point source.

[0005] To achieve the above objectives, the technical solution of this application embodiment is implemented as follows:

[0006] One embodiment of this application discloses a measuring device for a gamma point source, comprising:

[0007] A first detector is used to convert the X-rays emitted by the γ point source into a first pulse signal;

[0008] The second detector is used to convert the gamma rays emitted by the gamma point source into a second pulse signal;

[0009] The processing device is communicatively connected to the first detector and the second detector, respectively, and the processing device is able to obtain the activity value of the γ point source based on the first pulse signal and the second pulse signal.

[0010] In one embodiment, the first detector and the second detector are spaced apart, and the γ point source is disposed between the first detector and the second detector.

[0011] In one embodiment, the entrance window of the first detector is a beryllium window.

[0012] In one embodiment, the entrance window of the second detector is an aluminum window.

[0013] In one embodiment, the measuring device includes a bracket, the gamma point source is placed above the second detector, the bracket is positioned above the second detector, the first detector is fixed on the bracket, and the entrance window of the first detector faces the gamma point source.

[0014] In one embodiment, the measuring device includes a tray placed on top of the second detector, a support forming a test cavity having an upper opening and a lower opening, the first detector closing the upper opening, the tray disposed within the test cavity, the γ point source fixed on the tray, and the second detector closing the lower opening.

[0015] In one embodiment, the processing device includes:

[0016] A data acquisition unit, communicatively connected to the first detector and the second detector, is used to acquire the first generation time and the first pulse amplitude of the first pulse signal, and the second generation time and the second pulse amplitude of the second pulse signal;

[0017] A computing device is communicatively connected to the data acquisition unit. The computing device is able to obtain the count rate of X-rays, the count rate of γ-rays, and the count rate of anti-coincidence through anti-coincidence calculation based on the first generation time, the first pulse amplitude, the second generation time, and the second pulse amplitude, so as to obtain the activity value of the γ point source.

[0018] In one embodiment, the data acquisition unit uses leading-edge timing and trapezoidal filtering to obtain the first generation time, the first pulse amplitude, the second generation time, and the second pulse amplitude.

[0019] In one embodiment, the measuring device includes a BNC signal line, and the first detector and the second detector are respectively connected to the processing device through the BNC signal line.

[0020] Another aspect of this application provides a data processing method for the measuring device for a γ point source described in the above embodiments, the data processing method comprising:

[0021] The first detector responds to the γ point source to generate a first pulse signal, and the second detector responds to the γ point source to generate a second pulse signal;

[0022] The processing device acquires the pulse amplitude spectrum of X-rays, the pulse amplitude spectrum of γ-rays, and the relative delay time spectrum based on the first pulse signal and the second pulse signal.

[0023] The processing device calculates the activity value of the γ point source based on the pulse amplitude spectrum of the X-rays, the pulse amplitude spectrum of the γ-rays, and the relative delay time spectrum.

[0024] In one embodiment, the processing device calculates the activity value of the γ-ray point source based on the pulse amplitude spectrum of the X-rays, the pulse amplitude spectrum of the γ-rays, and the relative delay time spectrum, including:

[0025] The energy window of the X-ray is determined based on the pulse amplitude spectrum of the X-ray, the energy window of the gamma-ray is determined based on the pulse amplitude spectrum of the gamma-ray, and the delay time of the X-ray is determined based on the relative delay time spectrum.

[0026] The count rate of X-rays, the count rate of gamma rays, and the counter-coincidence count rate are calculated based on the energy window of the X-rays, the energy window of the gamma rays, and the delay time of the X-rays.

[0027] The activity value of the γ point source is calculated based on the count rate of the X-rays, the count rate of the γ-rays, and the anti-coincidence count rate.

[0028] In one embodiment, the processing device acquires the pulse amplitude spectrum of X-rays, the pulse amplitude spectrum of gamma rays, and the relative delay time spectrum based on the first pulse signal and the second pulse signal, including:

[0029] The processing device obtains a first generation time and a first pulse amplitude based on the first pulse signal and stores them as a first data file; the processing device obtains a second generation time and a second pulse amplitude based on the second pulse signal and stores them as a second data file;

[0030] The processing device extracts the pulse amplitude spectrum of the X-rays, the pulse amplitude spectrum of the gamma rays, and the relative delay time spectrum from the first data file and the second data file.

[0031] This application discloses a measurement device and data processing method for a gamma point source. A first detector measures the X-rays emitted by the gamma point source during decay and converts the X-rays into a first pulse signal. The decaying atomic nuclei of the gamma point source are in an excited state of daughter nuclei. By emitting gamma rays, the excited state returns to the ground state. A second detector then measures the emitted gamma rays and converts them into a second pulse signal. The processing device then obtains the activity value of the gamma point source based on the first and second pulse signals. This approach allows for direct measurement of the gamma point source, facilitating subsequent periodic calibration and improving the accuracy of gamma spectrometer measurement results. Furthermore, the measurement device directly measures the activity value of the gamma point source without requiring additional equipment or devices for pre-calibration, making it an absolute measurement device. This reduces uncertainty in multi-level magnitude transfer processes and improves the accuracy of gamma point source activity value measurement. Attached Figure Description

[0032] Figure 1 A schematic diagram of a measuring device for a gamma point source provided in an embodiment of this application;

[0033] Figure 2 A flowchart illustrating a data processing method provided in another embodiment of this application;

[0034] Figure 3 Another embodiment of this application provides a 54 Pulse X-ray spectra of Mn point source;

[0035] Figure 4 Another embodiment of this application provides a 54 Pulse amplitude diagram of gamma rays from Mn point source;

[0036] Figure 5 Another embodiment of this application provides a 54 The relative delay time spectrum of the Mn point source.

[0037] Explanation of reference numerals in the attached figures

[0038] Measuring device 100; first detector 1; second detector 2; processing device 3; data acquisition unit 3131; computing device 32; bracket 4; mounting cavity 4a; test cavity 4b; tray 5; BNC signal line 6; USB data line 7; γ point source 200. Detailed Implementation

[0039] It should be noted that, unless otherwise specified, the embodiments and technical features in the embodiments of this application can be combined with each other, and the detailed descriptions in the specific implementation should be understood as explanations of the purpose of this application and should not be regarded as undue limitations on this application.

[0040] The present application will now be described in further detail with reference to the accompanying drawings and specific embodiments. The terms "first," "second," etc., used in the embodiments of this application are for descriptive purposes only and should not be construed as indicating or implying their relative importance or implicitly including at least one feature. In the description of the embodiments of this application, "multiple" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0041] In related technologies, the activity value of a γ point source is measured by a γ spectrometer. However, as a relative measuring device, the γ spectrometer needs to be calibrated by a γ point source with a standard activity value before measurement. This multi-level value transfer process increases the measurement uncertainty.

[0042] In view of this, one embodiment of this application provides a measuring device for a gamma point source. Please refer to [link to relevant documentation]. Figure 1 The measuring device 100 includes a first detector 1, a second detector 2, and a processing device 3. The first detector 1 is used to convert X-rays emitted by the γ-ray point source 200 into a first pulse signal. The second detector 2 is used to convert γ-rays emitted by the γ-ray point source 200 into a second pulse signal. The processing device 3 is communicatively connected to the first detector 1 and the second detector 2, respectively, and is able to obtain the activity value of the γ-ray point source 200 based on the first pulse signal and the second pulse signal.

[0043] In this embodiment, the X-rays emitted by the γ-ray point source 200 during decay are measured by the first detector 1 and converted into a first pulse signal. The atomic nuclei of the γ-ray point source 200 after decay are in the excited state of daughter nuclei. By emitting γ-rays, the excited state returns to the ground state. At this time, the emitted γ-rays can be measured by the second detector 2 and converted into a second pulse signal. Then, the activity value of the γ-ray point source 200 is obtained by the processing device 3 based on the first and second pulse signals. In this way, on the one hand, the γ-ray point source 200 can be directly measured, which facilitates the subsequent periodic calibration of the γ-ray point source 200 and improves the accuracy of the γ-ray spectrometer measurement and analysis results. On the other hand, the measuring device 100 of this application directly measures the activity value of the γ-ray point source 200 without the need for additional equipment or devices for pre-calibration. It is an absolute measuring device, which can reduce the uncertainty in the multi-level transfer process and improve the accuracy of the γ-ray point source 200 activity value measurement.

[0044] In one embodiment, please refer to Figure 1The first detector 1 and the second detector 2 are arranged at intervals, and the gamma point source 200 is arranged between the first detector 1 and the second detector 2. For example, the first detector 1 and the second detector 2 can be arranged at intervals in the vertical direction, and the gamma point source 200 is arranged in the middle of the first detector 1 and the second detector 2. This facilitates the first detector 1 to measure X-rays and the second detector 2 to measure gamma rays, avoids energy attenuation of rays due to obstruction, and improves the acquisition accuracy of the first pulse signal and the second pulse signal.

[0045] In one embodiment, the entrance window of the first detector 1 is a beryllium window. This allows for more accurate X-ray measurement and effectively avoids interference from gamma rays, further improving the accuracy of the first pulse signal acquisition.

[0046] In one exemplary embodiment, the beryllium window has a thickness of 0.25 mm. This effectively avoids interference from gamma rays.

[0047] For example, in one embodiment, the detection core of the first detector 1 is a sodium iodide crystal. This results in high detection efficiency, high sensitivity, and large computing capacity.

[0048] For example, in one embodiment, the thickness of the sodium iodide crystal is 1 mm, which allows for the measurement of photons with energies in the range of 3 keV to 100 keV, providing a wide detection range.

[0049] In one embodiment, the entrance window of the second detector 2 is an aluminum window. This improves the detection efficiency of gamma rays and effectively shields low-energy X-rays, further enhancing the accuracy of the second pulse signal acquisition.

[0050] For example, in one embodiment, the aluminum window is 1 mm thick, which can effectively shield low-energy X-rays.

[0051] For example, in one embodiment, the detection core of the second detector 2 is a sodium iodide crystal. This results in high detection efficiency, high sensitivity, and large computing capacity.

[0052] For example, in one embodiment, the size of the detector core of the second detector 2 can be 76 mm in diameter and 76 mm in height, in order to improve the detection efficiency of gamma rays.

[0053] In one embodiment, please refer to Figure 1The measuring device 100 includes a bracket 4, with a gamma point source 200 positioned above the second detector 2. The bracket 4 is located above the second detector 2, and a first detector 1 is fixed to the bracket 4, with its entrance window facing the gamma point source 200. For example, a mounting cavity 4a is formed within the bracket 4, and the first detector 1 is fixed within the mounting cavity 4a. This improves the operational stability of the first detector 1.

[0054] In one embodiment, please refer to Figure 1 The measuring device 100 includes a tray 5, which is placed on top of the second detector 2. A support 4 forms a test cavity 4b, which has an upper opening and a lower opening. The first detector 1 closes the upper opening. The tray 5 is placed inside the measuring cavity, and a gamma point source 200 is fixed on the tray 5. The second detector 2 closes the lower opening. For example, the entrance window of the first detector 1 communicates with the measuring cavity through the upper opening, allowing X-rays emitted by the gamma point source 200 to enter the entrance window of the first detector 1 through the upper opening, effectively shielding gamma rays and improving the accuracy of acquiring the first pulse signal. The entrance window of the second detector 2 communicates with the test cavity 4b through the lower opening, allowing gamma rays emitted by the gamma point source 200 to enter the entrance window of the second detector 2 through the lower opening, effectively shielding low-energy X-rays and improving the accuracy of acquiring the second pulse signal.

[0055] In one embodiment, please refer to Figure 1 The processing device 3 includes a data acquisition unit 31 and a computing device 32. The data acquisition unit 31 is communicatively connected to the first detector 1 and the second detector 2, and is used to acquire the first generation time and the first pulse amplitude of the first pulse signal, as well as the second generation time and the second pulse amplitude of the second pulse signal.

[0056] The computing device 32 is communicatively connected to the data acquisition device 31. The computing device 32 can obtain the count rate of X-rays, the count rate of γ-rays and the count rate of anti-coincidence through anti-coincidence calculation based on the first generation time, the first pulse amplitude, the second generation time and the second pulse amplitude, so as to obtain the activity value of the γ point source 200.

[0057] In this embodiment, the first generation time and first pulse amplitude of the first pulse signal are acquired by the data acquisition device 31, and the second generation time and second pulse amplitude of the second pulse signal are acquired. The count rate of X-rays, the count rate of γ-rays, and the count rate of anti-coincidence are calculated by the computing device 32, and finally the activity value of the γ point source 200 is obtained. In this way, the activity value of the γ point source 200 can be directly set, which is convenient for subsequent calibration work. At the same time, since the anti-coincidence calculation is used, the problem of coincidence resolution time correction in coincidence measurement can be avoided.

[0058] In one embodiment, the activity value of the γ point source 200 is equal to the ratio of the product of the X-ray count rate and the γ-ray count rate to the difference between the γ-ray count rate and the anti-coincidence count rate. Thus, the activity value of the γ point source 200 can be calculated to provide a calibration value.

[0059] In one embodiment, the data acquisition unit 31 uses leading-edge timing and trapezoidal filtering to acquire the first generation time, the first pulse amplitude, the second generation time, and the second pulse amplitude. This improves the timing accuracy of the first and second generation times, provides high time resolution, and reduces the energy resolution loss of the first and second pulse amplitudes.

[0060] In one embodiment, please refer to Figure 1 The measuring device 100 includes a BNC signal line 6, and the first detector 1 and the second detector 2 are respectively connected to the processing device 3 through the BNC signal line 6. For example, the data acquisition unit 31 receives the signals output by the first detector 1 and the second detector 2 through the BNC signal line 6 and performs online processing, resulting in high transmission efficiency.

[0061] As an example, in one embodiment, please refer to Figure 1 The measuring device 100 includes a USB data cable 7. The data acquisition unit 31 transmits the first generation time, the first pulse amplitude, the second generation time, and the second pulse amplitude to the computing device 32 via the USB data cable 7 for subsequent calculation.

[0062] Another aspect of this application provides a data processing method; please refer to [link to relevant documentation]. Figure 2 The data processing method for the measuring device 100 for the γ point source in the above embodiments includes:

[0063] S1. The first detector responds to the γ point source to generate a first pulse signal, and the second detector responds to the γ point source to generate a second pulse signal.

[0064] For example, the first detector 1 is used to detect X-rays emitted by the γ point source 200 and convert the X-rays into a first pulse signal, and the second detector 2 is used to detect γ-rays emitted by the γ point source 200 and convert the γ-rays into a second pulse signal.

[0065] S2. The processing device acquires the pulse amplitude spectrum of X-rays, the pulse amplitude spectrum of γ-rays, and the relative delay time spectrum based on the first pulse signal and the second pulse signal.

[0066] S3. The processing device calculates the activity value of the γ point source based on the pulse amplitude spectrum of the X-rays, the pulse amplitude spectrum of the γ-rays, and the relative delay time spectrum.

[0067] In this embodiment, the X-rays and gamma rays emitted by the gamma point source 200 are detected by the first detector 1 and the second detector 2, respectively, and converted into a first pulse signal and a second pulse signal. Then, the processing device 3 obtains the pulse amplitude spectrum of the X-rays, the pulse amplitude spectrum of the gamma rays, and the relative delay time spectrum based on the first pulse signal and the second pulse signal. Finally, the activity value of the gamma point source 200 is calculated based on the pulse amplitude spectrum of the X-rays, the pulse amplitude spectrum of the gamma rays, and the relative delay time spectrum. In this way, on the one hand, the gamma point source 200 can be directly measured, so as to carry out subsequent periodic calibration of the gamma point source 200 and improve the quality of the gamma spectrometer measurement and analysis results; on the other hand, the data processing method of this application directly measures the activity value of the gamma point source 200 without the need for additional equipment or devices for pre-calibration. This can reduce the uncertainty in the multi-level transfer process and improve the accuracy of the gamma point source 200 activity value measurement.

[0068] In one embodiment, S3, the processing device calculates the activity value of the γ point source 200 based on the pulse amplitude spectrum of the X-rays, the pulse amplitude spectrum of the γ-rays, and the relative delay time spectrum, including:

[0069] S31. Determine the energy window of X-rays based on the pulse amplitude spectrum of X-rays, determine the energy window of γ-rays based on the pulse amplitude spectrum of γ-rays, and determine the delay time of X-rays based on the relative delay time spectrum.

[0070] S32. Calculate the X-ray count rate, the gamma-ray count rate, and the anti-coincidence count rate based on the X-ray energy window, the gamma-ray energy window, and the X-ray delay time.

[0071] S33. The activity value of the γ point source is calculated based on the count rate of the X-rays, the count rate of the γ-rays, and the anti-coincidence count rate.

[0072] For example, with 54 Taking the Mn point source as an example, 54 Place the Mn point source in tray 5 and begin measurement; Figure 3 As shown, Figure 3 for 54 The pulse amplitude spectrum of X-rays emitted from a Mn point source shows a full-energy X-ray peak of 5.4 keV at approximately channel 64. Based on the distribution range of the full-energy peak in the pulse amplitude spectrum, channels 40 to 90 are selected as the X-ray energy window. Figure 4 As shown, Figure 4 for 54 The pulse amplitude spectrum of gamma rays emitted from the Mn point source shows a full-energy peak of 834 keV at approximately channel 190. Based on the distribution of the full-energy peak in the pulse amplitude spectrum, channels 175-195 were selected as the energy window for gamma rays. Figure 5 The above, Figure 5 for 54 The relative time delay spectrum between X-rays and gamma rays emitted from a Mn point source. Figure 5 The horizontal axis represents the difference between the first and second generation times, and the vertical axis represents the count. Figure 5 It can be seen that the relative delay time between most of the first and second pulse signals is between -200 ns and 200 ns. Therefore, delaying the second generation time of the second pulse signal by 1 μs ensures that most of the second generation time is within the anti-coincidence time window of the first pulse signal. Based on the energy window of X-rays, the energy window of γ-rays, and the delay time of X-rays, the count rate of X-rays, the count rate of γ-rays, and the anti-coincidence count rate are calculated using anti-coincidence. Then, the ratio of the product of the X-ray count rate and the γ-ray count rate to the difference between the γ-ray count rate and the anti-coincidence count rate is used as the activity value of the γ-point source 200.

[0073] It should be noted that in the pulse amplitude spectrum mentioned above, the vertical axis represents the count, and the horizontal axis represents the pulse amplitude, i.e., the channel. The X-ray count rate is the ratio of the count corresponding to each pulse amplitude within the X-ray energy window to the total measurement time. Adding these ratios together gives the X-ray count rate. The gamma-ray count rate is the ratio of the count corresponding to each pulse amplitude within the gamma-ray energy window to the total measurement time, e.g., 100 s. Adding these ratios together gives the gamma-ray count rate. The anti-coincidence count rate is obtained by adding a delay time to the second generation time, then removing the gamma signal within the X-ray coincidence time window to obtain a new gamma-ray pulse amplitude spectrum. The anti-coincidence count rate is obtained by calculating the ratio of the count corresponding to each pulse amplitude within the new gamma-ray energy window to the total measurement time and adding these ratios together.

[0074] In one embodiment, S2, the processing device acquires the pulse amplitude spectrum of X-rays, the pulse amplitude spectrum of γ-rays, and the relative delay time spectrum based on the first pulse signal and the second pulse signal, including:

[0075] S21. The processing device obtains a first generation time and a first pulse amplitude based on the first pulse signal and stores them as a first data file; the processing device obtains a second generation time and a second pulse amplitude based on the second pulse signal and stores them as a second data file.

[0076] For example, the first data file has two vertical columns. The first column is the first generation time corresponding to each first pulse signal of X-rays, and the second column is the maximum value of the pulse amplitude of each first pulse signal of X-rays. The first generation time can be set by the data acquisition unit 31 with a first threshold. When the pulse amplitude of the first pulse signal exceeds the first threshold, the time of this point will be recorded as the first generation time. Then, the pulse amplitude of the second column is extracted to obtain the pulse amplitude spectrum of X-rays as shown in the figure.

[0077] The second data file has two vertical columns. The first column is the second generation time of each second pulse signal of gamma rays, and the second column is the maximum value of the pulse amplitude of each second pulse signal of gamma rays. The second generation time can be set by the data acquisition unit 31 with a second threshold. When the pulse amplitude of the second pulse signal exceeds the second threshold, the time of this point will be recorded as the second generation time. Then, the pulse amplitude of the second column is extracted to obtain the pulse amplitude spectrum of gamma rays as shown in the figure.

[0078] Determine the data in the first column of the first data file. For example, if the first generation time of the first X-ray pulse signal is 977599 ns, the corresponding pulse amplitude in the second column is 100; if the first generation time of the second first pulse signal is 28224497 ns, the corresponding pulse amplitude in the second column is 108. Then, find the data in the second data file. For example, if the second generation time of the first gamma-ray pulse signal is 582497 ns, the corresponding pulse amplitude in the second column is 34; if the second generation time of the second second pulse signal is 4066344 ns, the corresponding pulse amplitude in the second column is 36; if the second generation time of the third second pulse signal is 28224597 ns, the corresponding pulse amplitude in the second column is 38. Expand the coincidence time window range of the first generation time of the X-ray by 1 μs. For example, the coincidence time window of the first generation time of the first X-ray pulse signal is 977099 ns to 978099 ns. Then, we search for which of the second generation times in the first column of the second data file fall within the aforementioned coincidence time window. These signals are called coincidence signals. Obviously, the coincidence time window for the first generation time of the second first pulse signal of the X-ray does not fall within 977099 ns to 978099 ns. Obviously, the second generation time of the third second pulse signal in the second data file falls within this coincidence time window. Therefore, the second signal and the third signal in the first data file are called coincidence signals. Then, we calculate the difference between the first generation time and the second generation time corresponding to these two signals to obtain the relative delay time. For example, the difference between 28224497 ns and 28224597 ns is -100 ns. Finally, following the above steps, we process and statistically analyze the data in the entire first and second data files to obtain the relative delay time spectrum shown in the figure.

[0079] It should be noted that the acquisition rate of data acquisition device 31 is 500MS / s, so the above-mentioned generation time needs to be multiplied by 2 to get the actual signal generation time.

[0080] The above description is merely a preferred embodiment of this application and is not intended to limit the application. Various modifications and variations can be made to this application by those skilled in the art. All modifications, equivalent substitutions, improvements, etc., within the spirit and principles of this application are included within the scope of protection of this application.

Claims

1. A measuring device for a gamma point source, characterized in that The measurement device comprises: a first detector for converting X-rays emitted by the gamma point source into a first pulse signal; a second detector for converting gamma rays emitted by the gamma point source into a second pulse signal; a processing device comprising a data collector and a computing device, the data collector being in communication connection with the first detector and the second detector respectively, the data collector being configured to acquire a first generation time and a first pulse amplitude of the first pulse signal, and a second generation time and a second pulse amplitude of the second pulse signal, the computing device being in communication connection with the data collector, the computing device being capable of acquiring, according to the first generation time, the first pulse amplitude, the second generation time and the second pulse amplitude, a pulse amplitude spectrum of X-rays and a corresponding energy window of X-rays, a pulse amplitude spectrum of gamma rays and a corresponding energy window of gamma rays, and a relative delay time spectrum and a corresponding delay time of X-rays, and being capable of calculating, according to the energy window of X-rays, the energy window of gamma rays and the delay time of X-rays, a count rate of X-rays, a count rate of gamma rays and a count rate of anticoincidence, and taking a ratio of a product of the count rate of X-rays and the count rate of gamma rays to a difference between the count rate of gamma rays and the count rate of anticoincidence as an activity value of the gamma point source.

2. The measuring device of claim 1, wherein, The first detector and the second detector are arranged at intervals, and the gamma point source is arranged between the first detector and the second detector.

3. The measuring device of claim 1, wherein, The incident window of the first detector is a beryllium window.

4. The measuring device of claim 1, wherein, The incident window of the second detector is an aluminum window.

5. The measuring device of claim 2, wherein, The measurement device comprises a support, the gamma point source is placed above the second detector, the support is arranged above the second detector, the first detector is fixed on the support, and the incident window of the first detector faces the gamma point source.

6. The measuring device of claim 5, wherein, The measurement device comprises a tray, the tray is placed at the upper end of the second detector, the support is formed with a test cavity, the test cavity has an upper end opening and a lower end opening, the first detector closes the upper end opening, the tray is arranged in the test cavity, the gamma point source is fixed on the tray, and the second detector closes the lower end opening.

7. The measuring device of claim 1, wherein, The data collector acquires the first generation time, the first pulse amplitude, the second generation time and the second pulse amplitude by using front edge timing and trapezoidal filtering shaping.

8. The measuring device of claim 1, wherein, The measurement device comprises BNC signal lines, and the first detector and the second detector are connected to the processing device through the BNC signal lines respectively.

9. A data processing method, characterized by, The data processing method for the measurement device for the gamma point source of claim 1 comprises: a first detector responding to a gamma point source to generate a first pulse signal, and a second detector responding to the gamma point source to generate a second pulse signal; a processing device acquiring a pulse amplitude spectrum of X-rays, a pulse amplitude spectrum of gamma rays and a relative delay time spectrum according to the first pulse signal and the second pulse signal; the processing device calculating an activity value of the gamma point source according to the pulse amplitude spectrum of X-rays, the pulse amplitude spectrum of gamma rays and the relative delay time spectrum.

10. The data processing method according to claim 9, characterized in that, The processing device calculates the activity value of the gamma point source according to the pulse amplitude spectrum of the X-ray, the pulse amplitude spectrum of the gamma ray and the relative delay time spectrum, and the method comprises the steps of: determining an energy window of the X-ray according to the pulse amplitude spectrum of the X-ray, determining an energy window of the gamma ray according to the pulse amplitude spectrum of the gamma ray, and determining a delay time of the X-ray according to the relative delay time spectrum; calculating a count rate of the X-ray, a count rate of the gamma ray and a count coincidence rate according to the energy window of the X-ray, the energy window of the gamma ray and the delay time of the X-ray; calculating the activity value of the gamma point source according to the count rate of the X-ray, the count rate of the gamma ray and the count coincidence rate.

11. The data processing method according to claim 9, characterized in that, The processing device acquires the pulse amplitude spectrum of the X-ray, the pulse amplitude spectrum of the gamma ray and the relative delay time spectrum according to the first pulse signal and the second pulse signal, and the method comprises the steps of: The processing device acquires the first generation time and the first pulse amplitude according to the first pulse signal and stores them as a first data file; the processing device acquires the second generation time and the second pulse amplitude according to the second pulse signal and stores them as a second data file; The processing device extracts the pulse amplitude spectrum of the X-ray, the pulse amplitude spectrum of the gamma ray and the relative delay time spectrum from the first data file and the second data file.

Images