Comparison of the response of various TLDs to cosmic radiation and ion beams: Current results of the HAMLET project

Abstract

HAMLET is an European Commission research project aiming at optimal scientific exploitation of the data produced within the space experiment MATROSHKA. During phase 1 of this experiment a human phantom equipped with several thousands of radiation detectors (mainly TLDs) was exposed outside the International Space Station for 1.5 years. Besides the measurements realized in Earth orbit, the HAMLET project includes also a ground-based program of intercomparison of detector response to high-energy ion beams. Within the paper, the relative response of main glow-curve peaks of various TLDs (mostly based on LiF) used in frame of the MATROSHKA experiment by three laboratories (DLR Cologne, ATI Vienna and IFJ Krakow) for radiation in space and several ion beams, has been compared. For LiF:Mg,Ti detectors a very good agreement between results obtained by the three laboratories was observed, both for space and accelerator-based exposures. This should be considered a remarkable result, taking into account that the studied TLDs originated from six different batches, manufactured by two producers exploiting different production techniques and were processed by three laboratories, using significantly different protocols (annealing, readout, calibration, glow-curve analysis). Another type of TL detectors, LiF:Mg,Cu,P, was found to show response to cosmic radiation lower than that of LiF:Mg,Ti by 5%-18%.