ABSTRACT
Organ doses and effective doses of electrons and photons for the partial exposure using the MIRD-5 phantom and EGS-4 Code have been calculated. Irradiation geometries are AP and PA exposure. Calculations are carried out using 5 isocentered beams with different sizes to investigate the beam sizes effect on the effective dose. The results show that the effective doses depend not only on the energy of incident particle but also on the exposure position and the beam size on the body.
Subject(s)
Environmental Exposure , Radiometry/methods , Electrons , Humans , Particle Accelerators , Phantoms, Imaging , Photons , Radiation DosageABSTRACT
In this study spatial and time distribution of neutrons leaking from Hokkaido University 45 MeV Electron Linac facility have measured and compared with the Monte Carlo simulations. The neutron transport processes inside and outside the facility building has been simulated using MCNP. The neutrons have measured by BF3 counters and 3He counters with polyethylene moderators up to the distance of 330 m from the facility. The spatial distribution of ambient dose equivalent converted from the counts has been compared with the simulation. The distribution estimated from the counts by the BF3 counter has been shown fairly good agreement with the calculation. The spatial distribution of counts obtained at the 45 MeV Electron Linac facility has been compared with that obtained at the Fusion Neutronics Source (FNS) facility of JAERI. The difference between the propagation characteristics of neutrons leaking from those facilities has been discussed.