Relative HCP-to-gamma Thermoluminescent Efficiencies for TLD-100 Dosemeters Exposed to Low-energy Ions

Abstract

This work presents data and calculations of (HCP)‐to‐gamma TLD‐100 thermoluminescent efficiencies. Dosemeters were irradiated with low energy hydrogen, helium, carbon, nitrogen and oxygen ions. For nitrogen and oxygen two energies, corresponding to “mirror” values below and above the Bragg peak energy, were used to measure TL efficiencies for the same linear energy transfer (LET) entrance value. Efficiency results, both as a function of LET and energy, show distinct curves for each ion species. For energies above the Bragg peak energy, measurements show the well known tendency, efficiency values decrease with increasing LET. Data for energies lower than the Bragg peak display the opposite, efficiency increases with increasing LET. Results presented as a function of incident energy show that efficiency decreases with decreasing energy. For nitrogen and oxygen ions, the “mirror” measurements at higher energy (above the Bragg peak) are found to be 1.45 times greater than their low energy counterparts. Theoretical predictions based on Modified Track Structure Theory (MTST) show agreement with data within 40 % and predict the observed behavior, higher efficiency for higher ion energy.