Single-grain results from an EMCCD-based imaging system

Here we compare the performance of an EMCCD-based imaging system with the standard laser-based single-grain Risø attachment. We first compare gamma dose distributions and the relative sensitivity of the two instruments is investigated using a single sample, by comparing the number of grains accepted into a dose distribution. EMCCD cross-talk is shown to be of concern at low light levels. We also make use of the fact that the EMCCD can observe TL signals from individual grains to examine the use of the correlation between the quartz 110 °C TL peak and the fast component OSL signal to correct for sensitivity change. Finally, we present the OSL dose distributions from a set of both well-bleached and poorly-bleached sedimentary samples. From a comparison of the measured doses, we conclude that the two instruments give indistinguishable dose estimates and dispersions, despite the fact that the laser-based system is effectively about four times as sensitive as the EMCCD.