Application research of monochromatic micro x‐ray fluorescence in glass physical evidence traceability

Micro‐x‐ray fluorescence (μ‐XRF) is a commonly used elemental analysis technique for glass physical evidence in forensic cases, which can detect major and trace elements in samples and potentially identify glass fragments according to the differences in elemental composition. However, when a sample is irradiated with polychromatic x‐rays, bremsstrahlung scattering from the source radiation provides noise in the fluorescence spectrum and affects the detection results. To improve the signal‐to‐noise ratio of the fluorescence spectrum, a Mμ‐XRF spectrometer constructed under the low‐power Mo target x‐ray tube condition was used to analyze ten kinds of common glass fragments. The application of laboratory Mμ‐XRF analysis in single‐point detection of tiny glass materials was studied. Experimental results show that the detection limit of Sr element was 51 μg/L, and the spectrometer can distinguish different types of small glass fragments according to the fluorescence spectrum information.