Influence study on the electrodes' gamma-ray induced electron emission in array ionization chambers using MCNP code

In this paper, by carrying out MCNP simulations on the electron emission yield induced by 1.25 MeV rays from electrodes of C, Al, Fe, Cu, Ag, W, Pb in array ionization chamber models, we studied the influence of the electrodes' thickness and material on their gamma ray induced electron emission yields. The calculated results show that, with the increase of the thickness (over 0.01 mm) and the electron density of the electrodes, the yields of the emitted electrons from the array ionization chamber's electrodes decrease apparently, and that the length of the electrodes should be selected with due consideration of the electrodes' material. (authors)