Speaker
Description
A plastic scintillator (PLS) is a potential material for developing a dosimeter based on measurement of linear energy transfer (LET) for mixed radiation fields such as the accelerators' surroundings or in space because PLSs are composed mainly of hydrocarbon molecules, and have the effective atomic number and the density similar to those of water and human tissues. Additionally, there is a widespread application of PLSs in particle physics experiments due to their response to all types of radiation (photon, neutron, and charged particles). In order to employ PLSs in design and construction of LET spectrometer, some essential characteristics of PLSs are needed to be examined, such as the light yields as a function of energy deposited and radiation species, and the position sensitivity to observe tracks of incident radiation. Previously, we have performed the procedure for determining the energy deposited in a plastic scintillator (EJ-200) due to gamma rays from a Cs-137 radiation source using Compton Coincidence Technique (CCT). In the measurement, we found that the scintillation efficiency determined as a function of Compton electron energy approaches a saturation value at high energy region, and decreases in the region less than 100 keV. The decrease in the efficiency possibly pronounces the non-linearity between the light output and deposited energy. In this study, the scintillation efficiencies of PLSs (EJ-200, EJ-212, and EJ-252) are examined by focussing on the low energy region. In addition, the position sensitivity characteristic is examined by using four square-aligned PLS rods, multi-segmented photomultiplier tubes (PMTs) are attached to the both ends of the respective rods, and the positions of radiation incidence in the rod are measured by using signals from the PMTs. The experimental setups and results are given at the conference.
