CN-120491151-B - Neutron fluence response calibration method based on neutron generator reference radiation field

CN120491151BCN 120491151 BCN120491151 BCN 120491151BCN-120491151-B

Abstract

The application relates to the technical field of data calibration, in particular to a neutron fluence response calibration method based on a neutron generator reference radiation field, which comprises the steps of respectively acquiring counting rate and neutron fluence rate of each moment in each monitoring period and data of each environmental parameter around the reference radiation field in each moment in each monitoring period through a neutron detector and a neutron generator; recording each monitoring period and a plurality of monitoring periods before the monitoring period as each historical period, determining the measurement error degree of each historical period, obtaining the measurement interference degree of each environmental parameter under each monitoring period, calculating the scattering interference degree of each environmental parameter under each monitoring period, obtaining the calibration counting rate, and carrying out real-time calibration on the medium fluence response. According to the application, the interference influence of different environmental factors on the measurement result of the neutron detector can be quantified through dynamic environmental changes, the measurement result of the neutron detector is calibrated in real time, and the measurement accuracy of the neutron fluence response is improved.

Inventors

FENG ZHIMING
XIA XUNRONG
GU JIAYU
XING LITENG
JIANG WEI
Hu zunhao

Assignees

江苏省计量科学研究院(江苏省能源计量数据中心)

Dates

Publication Date: 20260508
Application Date: 20250604

Claims (10)

1. A neutron fluence response calibration method based on a neutron generator reference radiation field, the method comprising the steps of: the method comprises the steps of respectively collecting counting rate and neutron fluence rate of each moment in each monitoring period and data of each moment in each monitoring period of each environmental parameter around a reference radiation field through a neutron detector and a neutron generator; Analyzing the discrete condition of the counting rate, the correlation condition of the counting rate and the neutron fluence rate in each history period and the difference condition of the change trend between the counting rate and the neutron fluence rate, and determining the measurement error degree of each history period; Clustering the measurement error degrees of all the historical periods, and analyzing the dispersion condition of the average level of the data of different historical periods in each cluster under each environmental parameter and the correlation condition of the average level of the data of each environmental parameter in different historical periods and the measurement error degree to obtain the measurement interference degree of each environmental parameter under each monitoring period; Screening all the historical periods based on the related conditions of data and counting rate of each environmental parameter at all times in each historical period and the difference conditions of the data and counting rate and the measured interference degree to obtain each significant period; Calculating the scattering interference degree of each environmental parameter in each monitoring period through the deviation condition of the data and the deviation condition of the counting rate of each environmental parameter in different obvious periods, calibrating the counting rate of each moment in the next monitoring period respectively to obtain the calibrated counting rate of each moment in the next monitoring period, and calibrating the medium fluence response in real time.
2. The neutron fluence response calibration method based on a neutron generator reference radiation field of claim 1, wherein the environmental parameters include temperature, humidity and air pressure.
3. The neutron fluence response calibration method based on a reference radiation field of a neutron generator of claim 1, wherein the determining the measure error degree for each historical period comprises: calculating the discrete degree of the counting rate at all times in each history period, and recording the discrete degree as a first discrete degree; calculating the correlation degree of the counting rate and the neutron fluence rate at all moments in each history period, marking the correlation degree as a first correlation degree, and carrying out positive mapping on the first correlation degree; Analyzing the difference condition between the linear change trend of the counting rate and the linear change trend of the neutron fluence rate in each history period, and calculating the linear deviation; The measurement error degree is the ratio between the product value and the result of the positive mapping.
4. The method for calibrating neutron fluence response based on a reference radiation field of a neutron generator as defined in claim 3, wherein calculating the linear deviation comprises linearly fitting the count rate and the neutron fluence rate at all times in each history period respectively, calculating slopes of a fitting straight line respectively, and marking a difference between the first slope and the second slope as the linear deviation.
5. The method for calibrating neutron fluence response based on a reference radiation field of a neutron generator according to claim 1, wherein the obtaining the measured interference level of each environmental parameter for each monitoring period comprises: calculating the dispersion degree of the average value of all the history periods of each environmental parameter in each cluster, and recording the dispersion degree as the intra-cluster fluctuation degree; calculating variation coefficients of the intra-cluster fluctuation of all the clustered clusters under each environmental parameter; calculating the correlation degree between the average value of all history periods and the measurement error degree under each environmental parameter, and recording the correlation degree as a second correlation degree; the measured interference degree is a normalized result of the product of the second correlation degree and the variation coefficient.
6. The neutron fluence response calibration method based on a neutron generator reference radiation field of claim 1, wherein the process of obtaining each salient period is: Calculating the correlation degree between the data and the counting rate of each environmental parameter at all times in each historical period, and recording the correlation degree as a third phase Guan Du; and recording the history period corresponding to the discrimination coefficient greater than or equal to 0 as each significant period.
7. The method of calibrating neutron fluence response based on a reference radiation field of a neutron generator according to claim 1, wherein the calculating the degree of scattering interference for each environmental parameter for each monitoring period comprises: Analyzing the distribution condition of the counting rate in the standard reference period and the distribution condition of the data of each environmental parameter in the standard reference period, and determining the standard counting rate and the standard value corresponding to each environmental parameter; Calculating the difference between the counting rate at each moment in each significant period and the standard counting rate, and recording the difference as a first difference; calculating the difference between the data of each environmental parameter at each moment in each obvious period and the standard value, and recording the difference as a second difference; The average value of the ratio of the first difference value to the second difference value of each environmental parameter at all moments in each obvious period is recorded as an interference coefficient; The degree of scattering interference is the mean value of the interference coefficients for all significant periods under each environmental parameter.
8. The neutron fluence response calibration method based on the neutron generator reference radiation field of claim 7, wherein the determining the standard count rate and the standard value corresponding to each environmental parameter includes counting the modes of the count rates at all times in a standard reference period as the standard count rate and counting the modes of the data at all times in the standard reference period as the standard value for each environmental parameter.
9. The method of calibrating neutron fluence response based on a reference radiation field of a neutron generator of claim 8, wherein obtaining the calibrated count rate for each moment in the next monitoring period comprises: First, the Seed environmental parameter pair first Within the monitoring period Counting rate after calibration at each moment The calculation formula of (2) is as follows: , wherein, Is the first Within the monitoring period The count rate before calibration of the individual moments in time, Is the first The seed environment parameter is at the first Within the monitoring period The data of the individual moments in time are, Is the first The standard value corresponding to the environmental parameter, Is the first The following monitoring period Scattering interference degree of seed environmental parameters; and taking the average value of the counting rates of all environmental parameters after calibration at each moment in the next monitoring period as the calibrated counting rate at each moment in the next monitoring period.
10. The method for calibrating neutron fluence response based on a reference radiation field of a neutron generator as defined in claim 1, wherein the step of calibrating the neutron fluence response in real time comprises using a ratio of the calibrated count rate to the neutron fluence rate as the neutron fluence response calibrated at each moment in the next monitoring cycle.

Description

Neutron fluence response calibration method based on neutron generator reference radiation field Technical Field The application relates to the technical field of data calibration, in particular to a neutron fluence response calibration method based on a neutron generator reference radiation field. Background The neutron generator is a compact accelerator device for generating neutrons through nuclear reaction, and is widely applied to the fields of medicine, material analysis, nuclear industry and the like, and is used for generating neutrons. Neutron detectors are an instrument used to monitor and measure neutrons. In order to ensure that the detection precision of the neutron detector can meet the detection requirement, the detector needs to be calibrated according to the response characteristic of neutrons, so that the calibrated detector can accurately measure neutron fluence, the reliability and consistency of measurement results are improved, and the safety and effectiveness of neutron related application are ensured. The reference radiation field is used as a key basis for neutron detector calibration, and is a specific radiation field for calibrating and measuring neutron fluence. The existing neutron reference radiation field is built based on an isotope radioactive source, although the wide energy domain can be covered, the influence of different environmental factors on neutron fluence measurement is not fully considered in the actual calibration process, for example, the environmental factors can change the molecular density in air gas, so that the elastic scattering of neutrons is increased, the neutron beam intensity is attenuated, the measurement result of a neutron detector is error, meanwhile, the scattering interference of different environmental factors on the radiation field is different, the calibration result of the neutron detector is offset, dynamic environmental change cannot be adapted, the accuracy of calibrating the measurement result of the neutron detector is influenced, and the measurement accuracy of the neutron fluence response is lower. Disclosure of Invention In order to solve the technical problems, a neutron fluence response calibration method based on a neutron generator reference radiation field is provided to solve the existing problems. The technical problem is solved by the application by providing a neutron fluence response calibration method based on a neutron generator reference radiation field, which comprises the following steps: the method comprises the steps of respectively collecting counting rate and neutron fluence rate of each moment in each monitoring period and data of each moment in each monitoring period of each environmental parameter around a reference radiation field through a neutron detector and a neutron generator; Analyzing the discrete condition of the counting rate, the correlation condition of the counting rate and the neutron fluence rate in each history period and the difference condition of the change trend between the counting rate and the neutron fluence rate, and determining the measurement error degree of each history period; Clustering the measurement error degrees of all the historical periods, and analyzing the dispersion condition of the average level of the data of different historical periods in each cluster under each environmental parameter and the correlation condition of the average level of the data of each environmental parameter in different historical periods and the measurement error degree to obtain the measurement interference degree of each environmental parameter under each monitoring period; Screening all the historical periods based on the related conditions of data and counting rate of each environmental parameter at all times in each historical period and the difference conditions of the data and counting rate and the measured interference degree to obtain each significant period; Calculating the scattering interference degree of each environmental parameter in each monitoring period through the deviation condition of the data and the deviation condition of the counting rate of each environmental parameter in different obvious periods, calibrating the counting rate of each moment in the next monitoring period respectively to obtain the calibrated counting rate of each moment in the next monitoring period, and calibrating the medium fluence response in real time. Preferably, the environmental parameters include temperature, humidity and air pressure. Preferably, the determining the measurement error degree of each history period includes: calculating the discrete degree of the counting rate at all times in each history period, and recording the discrete degree as a first discrete degree; calculating the correlation degree of the counting rate and the neutron fluence rate at all moments in each history period, marking the correlation degree as a first correlation degree, and carrying out positive mapping on the f