Numerical Investigation on Radiation Dose in Vacuum Tank of 100 MeV High Intensity Proton Cyclotron

In CIAE’s 100 MeV high intensity proton cyclotron, the H^-issociation caused by residual gas and Lorentz stripping during acceleration can make some beam losses and result in radioactivity. Monte-Carlo method is used to simulate the dose equivalent rate distribution in the circumference direction of outside wall of the vacuum tank when the machine is running. The simulated result shows that the maximum value of it is about 143 Sv/h. At the same time, the residual radiation field distribution in the vacuum tank and its decay with time were estimated after the machine is shut down.