Enhancing Accuracy In EMCCD Measurements Of Luminescence From Single Grains Through Minimising Signal Crosstalk

This study addresses the challenge of signal crosstalk in luminescence measurements from single sand-sized mineral grains, utilising Electron-Multiplying Charge-Coupled Devices (EMCCD) for imaging. Crosstalk, or signal interference between adjacent grains, may significantly hamper the accuracy of luminescence analysis of signals emitted by single mineral grains. The research aims to minimise crosstalk, thereby enhancing the integrity of the luminescence data from each grain. The effects of altering the aperture size and the spacing between grains on the sample disc are investigated using the 110◦C thermoluminescence (TL) peak of quartz as an example. Specifically, the introduction of a newly designed sample disc with increased spacing between grain holes shows promising results in mitigating signal overlap, as evidenced by the experimental data. In particular, we demonstrate that the new design dramatically decreases signal crosstalk, enabling reliable automatic data analysis with minimal interference. The study offers practical solutions for enhancing the reliability of single-grain based luminescence chronologies and dosimetric assessments. By minimising signal crosstalk, more precise and reliable analyses of thermoluminescence and OSL signals can be obtained. To demonstrate the potential of the new design, for the first time, we show the estimation of trap parameters of the 110◦C peak in quartz at a single-grain level using an EMCCD camera, comparing it with the lifetime of the electrons in the 110◦C trap measured directly through storage experiments.