THE EFFICIENCY OF VARIOUS THERMOLUMINESCENCE DOSEMETER TYPES TO HEAVY IONS

Abstract

Dose verification in heavy-ion beams using passive dosemeter systems, e.g. thermoluminescence dosemeters (TLDs), is crucial due to the changing efficiency of the dosemeters for different ion species and linear energy transfer (LET) values. This behaviour leads to a falsification of absorbed dose that can be significant for many applications, e.g. in space or radiotherapeutic dosimetry. TLDs can only be established as a ‘reference’ system in heavy-ion beams or other radiation fields if the efficiency functions for all contributing ion species and LET values are provided. In the framework of a research project of the Atominstitute of the Austrian Universities irradiations with various ions were performed in the years 2001–2003 at the Heavy Ion Medical Accelerator (HIMAC) of the National Institute for Radiological Sciences (NIRS) in Chiba, Japan. Efficiency values were recorded in dependence on ion species and LET in a range from 2 to 400 keV µm^-1. The efficiencies of five different commercially available TLD materials namely TLD 600, TLD 700, TLD 700H, TLD 300 and TLD 200 were investigated.