Geant4 Step towards the Durability and Smooth Response of Silicon Based Neutron Dosimeter, and Protection from Thermal Neutrons

摘要

Responses and durability of energy independent neutron dosimeters based on proton detector microchips covered with segmented multi-thickness polythene (PE) layers are badly affected by the slow neutrons produced in the process. Here, we report the shielding of slow neutrons by using 0.9 cm thick cadmium layer, which is transparent to fast neutrons. This is achieved by using 15 MeV beam of 10⁷ number of neutrons incident on poly methyl methacrylate-aluminum-cadmium (PMMA-Al-Cd) multiple layers by means of a Monte Carlo method. The results can be used in real time dosimeters for measuring the tissue equivalent neutron doses, and for optimizing the shielding of thermal neutrons in the vicinity of proton therapy centers.