X-ray Energy Spectrum Measurements Based On The Al₂O₃:C Crystal RL

X-ray tube has been widely used in medicine,biology,material analysis and nondestructive testing,therefore it is very important to confirm the generated energy spectrum of X-ray tube.With this we can evaluate the performance of radiation devices which is of great significance to the dose estimation,the improvement of the devices and the design of target materials.Pulse x ray radiation is of high strength,has a wide ranging energy spectrum and a short pulse duration.To directly measure the Xray energy spectrum,we need high precision,high resolution,high count rate detection but we also must ensure efficient screening in the electromagnetic interference environment under test signals.This in practise proves to be very challenging.X-ray tube spectroscopy is a technical problem in the field of nuclear science.In this paper,based on the research results of X-ray energy spectrum measurements taken at home and abroad,based on the Al₂O₃:C crystal RL dosimetry method,an experimental platform is set up to realize the X-ray energy spectrum measurement system of the absorption method.The detector response function of the experimental platform is calculated by the monte carlo program.In order to solve the problem of ill-posed response function matrix in the process of spectral solution,gauss-seidel iteration,Richardson＿Lucy iteration and maximum-expectation method are selected to solve the problem,and the results of various iterative methods are compared.In this paper,an X-ray tube in the laboratory is measured using an experimental platform,and the X-ray energy spectrum is obtained by analysis,which verifies the measurement system and method technology.Through the above research,the results of the paper are as follows:（1）A set of X-ray energy spectrum measurement system based on the absorption method is established by combining the RL and OSL dose measurement technology of Al₂O₃:C crystal with the X-ray energy spectrum measurement technology of the absorption method.（2）According to the principle of the X-ray energy spectrum measurement by the absorption method,the selection requirements of detection crystal and filter material in the measurement system are analyzed,and the detector is developed.（3）The MCNP simulation experiment of X-ray spectrum measurement by the absorption method is carried out by selecting the spectral lines of N series additional filter reference radiation in iso4037 report.The Gauss Seidel iteration algorithm and Richardson are compared＿The iterative results of Lucy iterative algorithm and maximum expectation method.The results show that the traditional iterative method is not suitable for the absorption method＿In order to find the approximate initial value,Lucy iterative method is not suitable for the solution spectrum of the absorption method.The maximum expectation method has the advantages of fast iterative speed and insensitivity to the initial iterative spectral line.In this paper,the maximum expectation method is chosen as the iterative method of the absorption method,and the spectral software is written.（4）Aiming at a certain type of X-ray tube in the laboratory,the Al2O3:C measuring system developed in this paper is used for dose measurement,and the X-ray energy spectrum analysis is carried out.The test results are compared with the simulation results to verify the accuracy of the system and method.Due to the limitation of time,the paper is not able to use the OSL method for theoretical calculation and experimental analysis.In the follow-up study,we can carry out the method research of RL and OSL combined dose measurement,and further improve the system and measurement method.