Fundamental Technology Research On Air-kerma Standard Device For Gamma Ray At Protection Level

Gamma (γ) ray technology has been widely applied to the industrial sectors and the scientific researchfield. Air-kerma standard device of Gamma ray has been set up in the foreign countries; however, ourcountry still used the old standard based on the“exposure”. In order to facilitate the internationalcooperation and research, the national metrology bureau has decided to change the ionizing radiationmeasurement unit, therefore the many relatively existing kerma targets couldn’t be carried out traceabilityand calibration so far, and the following questions are also needed to be solved. The air-kerma, as animportant physical quantity in the ionizing radiation field, is the important research base of the ionizingradiation metrology work. It is of urgency for the new criterion. According to the standard constructionproject,“The design and research of Gamma ray air-kerma standard device”, from the Test TechnologyResearch Institute of China, the thesis has carried out the preliminary study of relative fundamentaltechnology of“air-kerma standard device for gamma ray at protection level”, to make efforts in layingfoundations of setting up the standard device .Besides the study of development, present situations and tendency of the Gamma ray radiationmeasurement in the domestic and foreign, the thesis also analyses the characters of exposure and air-kermafor gamma rays, their various effects about the inter-reaction with the materials( such as photoelectric effect,Compton effect, electron pair effect ), carries out the preliminary study of relative fundamental technology,such as Gamma ray radiation source technology, the detector and the weak current measurement technology,automatic measuring method and error analysis, verifies the experiments and so on .The results of the thesis is to set up a set of the protective level gamma radiation testing equipmentbased on the air-kerma , and to finish a set of automatic air-kerma calibration system , so as to layfoundations for the standard device of air-kerma for gamma ray at protection level.