Luminescence efficiency of Al2O3:C,Mg radiophotoluminescence in charged particle beams

Abstract In hadron therapy, it is important to evaluate how sensitive a detector is upon radiation with varying ionization densities, i.e. linear energy transfer (LET), as the LET changes when penetrating through material. For solid-state detectors, it is therefore essential to characterize the luminescence efficiency ( η HT , γ ) of the detector as a function of LET. In this work, we investigate the radiophotuminescence (RPL) response from Al 2 O 3 :C,Mg 2D films and crystals exposed to various high LET beams ( 1 H, 4 He, 12 C, 28 Si and 56 Fe). The measured η HT , γ curve from RPL films and crystals as function of the particle LET is compared with the η HT , γ curve from Al 2 O 3 :C OSL samples. Furthermore, a 2D RPL image, from Al 2 O 3 :C,Mg films irradiated with a 61.3 MeV 40 mm diameter broad proton beam, depicts a 2D depth dose distribution of the Bragg peak and demonstrates similar LET dependence as from the luminescence efficiency curve. The η HT , γ curves are consistent with Birks’ law, where we observe expected quenching for increasing LET.