Research Of Gamma-ray Self-absorption Correction For The Volume Source

It is required to check the matrix and radionulide of the radioactive waste drums, which are produced in the process of nuclear facilities production and retired. It is one of the key technologies of radioactive waste drums assay that gamma-ray self-absorption correction. With the segmented gamma scanning technology(SGS), gamma-ray self-absorption correction of volume source sample has been studied in the radioactive waste drums. Model of HPGe detector and detection system have been established by the Monte Carlo method, and then gamma-ray self- absorption correction of volume source have been simulated for many different samples. It shows that correction results are accurate and effective by experimentally validated, which improve the accuracy of measurement for radioactive samples. A variety of heterogeneous samples are built in the experiment. This work has explored the effect of different density heterogeneity and position migration of emission source in SGS analysis for radioactive waste drums. It is proved that density heterogeneity determines relative deviation directly in SGS analysis. Density of sample, energy and transmission ability of gamma-ray and radionuclide position migration are the important effect factors of analysis devi ation of gamma-ray self-absorption correction. So it's very important for reducing analysis deviation to known material composition of samples and distribution of radionuclides. It provides an effective method to reduce the analysis deviation that reducing sample's size and radius suitably, measuring low density samples. Th is work provides a reference for gamma-ray self-absorption correction of volume source sample technology and it has a certain value.