Hope College Physics Department Research Experiences for Undergraduates Summer 2007 Project Summary

The goal of this project was to fully develop a cost-effective and non-destructive method for the comparison of glass samples for forensic study. This ion beam analysis technique can quantify trace elements in glass once the samples have been prepared through a thorough surface cleaning and special slide-mounting procedure to avoid contamination and orientation effects. A Van de Graaff particle accelerator was used to collect PIXE spectra of glass samples and standards with 3.4 MeV protons. RBS (Rutherford Backscattering) data was simultaneously collected for all samples, and was used to normalize the average beam current on target. The PIXE data was then analyzed using GUPIXWin© to determine a concentration of nine different trace elements found in the samples. By comparing the concentrations of the trace elements, glass samples that were from different sources were able to be effectively distinguished, and a statistical analysis protocol of the PIXE data was developed to ascertain the likelihood of any two samples being from different sources.
_________________________________________________________________________________________________________________________Publications Publications and Presentations:
"Development of an Ion Beam Analysis Method for Forensic Analysis of Glass", Richard Sampson*, Graham F. Peaslee, Paul A. DeYoung, Christopher Hall*, Derek Padilla*, and Patrick Mears*. American Academy of Forensic Sciences 2008 Annual Meeting, Denver, Colorado, (2008).