The Design Of A High Performance Environment Gammer Ray Monitor

In our living world, there is radiation everywhere. But there are few radiation monitor used for environment radiation monitoring. In this paper, the design of a high performance ionization chamber filled with high pressure argon monitor for environment gamma ray detect is introduced. Normally, for the design of gas detector, the energy response of the working gas and the material for the chamber is the key element to the detector, and the choosing of the working gas and the material influent the performance of the detector directly. In the process of the design of gas detector, it is usually by the ways of refer to the energy response graphic of the working gas and the material for the chamber to choose the working gas and the material for the chamber. But in the case that the information of working gas and the material for the chamber is not available, the experiment is taken, and that will always cost much and need much time. To overcome this shortcoming in the design, in this paper, the MCNP and EGSnrc code is used to take the place of the experiment. A model is setup in the MCNP and EGSnrc code to compare the influence of different working gas and the material for the chamber on the detector, and find the good choices of working gas and chamber material with high performance for the detector. And the pressure and the diameter of the detector is choosed with the simulation of the MCNP and EGSnrc code.To prevent the current leakage of the ionization chamber a three co-axis insulator is used, and the result is good.For the current in the ionization chamber is not amplified, so it is hard to collect the electric signal, in this paper, a direct I/F convertor is used to convert the electric current signal into frequent signal.