Track Structure Theory - Track Intersection Model for Heavy Charged Particle Thermoluminescence Dose Response Curves

Abstract

Abstract Alpha particle thermoluminescence (TL) dose response curves are almost always linear-sublinear rather than linear-supralinear-sublinear as observed with gamma rays and electrons. The model presented herein is a variable ionisation density track intersection model which shows that heavy charged particle (HCP) supralinearity does not exist because the highly localised nature of the HCP track radial dose distribution suppresses the probability of significant track intersection at dose levels where gamma ray or electron supralinearity is normally encountered. The model calculates the TL yield due to intersecting alpha particle tracks by folding in the summed dose from two alpha particle tracks with the TL dose response generated by low energy electrons matched as closely as possible in energy to the primary electron spectrum liberated by the alpha particles. The calculations show that there is no inter-track distance for which the total TL yield for two intersecting alpha particle tracks is greater than twice the TL yield of a single alpha particle track. The immediate conclusion is that alpha particle supralinearity cannot exist for glow peaks with electron TL dose response curves normally encountered in most TL materials.