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Shooting distance determination by m-XRF--examples on spectra interpretation and range estimation
Silke Latzel1, Dieter Neimke, Rüdiger Schumacher
1Bundeskriminalamt (Federal Criminal Police Office), KT 23, 65173 Wiesbaden, Germany. Silke.latzel@bka.bund.de
Forensic Science International
|October 31, 2012
Summary
X-ray fluorescence (XRF) effectively detects lead-free gunshot residue (GSR). Elemental mapping from milli-X-ray fluorescence (m-XRF) aids shooting distance determination, enhancing accuracy with multi-element analysis and a new numerical tool.
Area of Science:
- Forensic Science
- Analytical Chemistry
- Materials Science
Background:
- Modern ammunition increasingly uses lead-free formulations, posing challenges for traditional gunshot residue (GSR) detection methods.
- Accurate determination of shooting distance is crucial in forensic investigations.
Purpose of the Study:
- To evaluate the utility of X-ray fluorescence (XRF) for detecting lead-free GSR.
- To explore the application of elemental mapping via milli-X-ray fluorescence (m-XRF) for shooting distance estimation.
- To present a numerical tool for analyzing GSR elemental data and differentiating shooting distances.
Main Methods:
- Utilized X-ray fluorescence (XRF) for multi-element detection of GSR particles.
- Employed milli-X-ray fluorescence (m-XRF) to generate elemental maps of GSR deposits.
- Developed and applied a numerical tool for processing and visualizing elemental mapping data.
Main Results:
- XRF's multi-element detection capability proved effective for identifying lead-free GSR.
- Elemental mapping from m-XRF provided a reliable method for shooting distance estimation, analogous to chemographic imprints.
- Incorporating multiple elements in mapping analysis significantly improved the reliability of shooting range estimations.
- A numerical tool was developed to aid in the differentiation of shooting distances based on GSR data.
Conclusions:
- XRF and m-XRF elemental mapping offer a robust approach for analyzing lead-free GSR.
- The presented numerical tool enhances the accuracy and reliability of shooting distance determination in forensic investigations.
- While promising, full automation of spectra interpretation requires further development, with experienced user verification remaining essential.
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